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Simcenter STAR-CCM+ 附带了一些加载项，可为特定工程应用的模拟提供专用方法 - Electronics Cooling Toolset和 Simcenter STAR-CCM+ In-cylinder 解决方案。
Simcenter STAR-CCM+ In-cylinder Solution
Simcenter STAR-CCM+ In-cylinder Solution provides a simplified approach within Simcenter STAR-CCM+ to perform transient moving-mesh simulations of internal combustion engines (ICE).
Simcenter STAR-CCM+ In-cylinder 参考
Simcenter STAR-CCM+ In-cylinder 为对象树中的各种对象提供特定的右键单击操作和属性。
Models
The following right-click actions and dialogs are available for models in Simcenter STAR-CCM+ In-cylinder.

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加载项
Simcenter STAR-CCM+ 附带了一些加载项，可为特定工程应用的模拟提供专用方法 - Electronics Cooling Toolset和 Simcenter STAR-CCM+ In-cylinder 解决方案。
- Electronics Cooling Toolset
  Electronics Cooling Toolset在 Simcenter STAR-CCM+ 中提供了一个简化的方法来模拟电子设备的热管理，从设计到求解分析全部涵盖在内。
- Simcenter STAR-CCM+ In-cylinder Solution
  Simcenter STAR-CCM+ In-cylinder Solution provides a simplified approach within Simcenter STAR-CCM+ to perform transient moving-mesh simulations of internal combustion engines (ICE).
  - ICE 机制
    内燃机的开发和改进源自缸内流的系统分析。Simcenter STAR-CCM+ In-cylinder 能够模拟在四冲程或二冲程循环中以稳定速度运行的往复式内燃机的缸内流。
  - Geometry Requirements
    For the automated setup of an internal combustion engine in Simcenter STAR-CCM+ In-cylinder, the geometry that you import must meet certain criteria. These criteria concern the file format as well as the positions and names of bodies and faces.
  - 阀门运动
    Simcenter STAR-CCM+ In-cylinder 使用阀升程曲线对阀运动进行建模。
  - 活塞运动
    要对活塞运动建模，Simcenter STAR-CCM+ In-cylinder 需要有关发动机几何的特定信息。
  - Fuel Injection
    Simcenter STAR-CCM+ In-cylinder provides methods for predicting the charge motion in an internal combustion engine—from fuel injection to fuel evaporation to air-fuel vapor mixing.
  - 燃烧和点燃
    Simcenter STAR-CCM+ In-cylinder 为模拟内燃机中的燃烧过程提供了有效方法。
  - Mesh Strategy
    Simcenter STAR-CCM+ In-cylinder generates a trimmed mesh with automatic volumetric refinements to account for various flow characteristics within the flow domain. For a cylinder sector model, Simcenter STAR-CCM+ In-cylinder generates an axisymmetric mesh.
  - Solution Analysis
    Simcenter STAR-CCM+ In-cylinder allows you to analyse the solution of an ICE simulation while the simulation is running as well as when the simulation completes.
  - Simcenter STAR-CCM+ In-cylinder 工作流
    要在 Simcenter STAR-CCM+ In-cylinder 中对发动机循环问题进行设置、运行和后处理，需要从上至下使用相关节点。
  - Simcenter STAR-CCM+ In-cylinder 故障排除
    如果在设置或运行 ICE 模拟时遇到问题，可以查看这些常见的问题情景，以获取有关如何继续操作的建议。此外，也可以查看支持中心门户上的知识库。
  - Simcenter STAR-CCM+ In-cylinder 参考
    Simcenter STAR-CCM+ In-cylinder 为对象树中的各种对象提供特定的右键单击操作和属性。
    - 几何
      以下右键单击操作和对话框可用于 Simcenter STAR-CCM+ In-cylinder 中的几何。
    - Models
      The following right-click actions and dialogs are available for models in Simcenter STAR-CCM+ In-cylinder.
    - 材料
      以下右键单击操作和对话框可用于 Simcenter STAR-CCM+ In-cylinder 中的材料。
    - 参数
      以下右键单击操作和对话框可用于 Simcenter STAR-CCM+ In-cylinder 中的参数。
    - Engine
      The following right-click actions and dialogs are available for Engine Parts in Simcenter STAR-CCM+ In-cylinder.
    - 操作条件
      以下右键单击操作和对话框适用于 Simcenter STAR-CCM+ In-cylinder 中的操作条件。
    - 求解器
      以下右键单击操作和对话框可用于 Simcenter STAR-CCM+ In-cylinder 中的求解器。
    - 网格
      以下右键单击操作和对话框可用于 Simcenter STAR-CCM+ In-cylinder 中的网格。
    - 结果
      对于绘图、报告和场景，Simcenter STAR-CCM+ In-cylinder 提供了 Simcenter STAR-CCM+ 中相应对象可用的一部分右键单击操作和属性。
    - 图形窗口 — 互动右键单击操作
      Simcenter STAR-CCM+ In-cylinder 为几何和发动机零部件提供了各种互动标注尺寸和定位功能。
    - 坐标系
      Simcenter STAR-CCM+ In-cylinder 使用多个坐标系来创建几何、定义活塞和阀运动、设置喷射器或进行后处理。
  - Simcenter STAR-CCM+ In-cylinder 公式
- Application Productivity Tools
  Application Productivity Tools (APTs) are specialized add-ons that allow you to focus on specific applications. These tools are available as plugins for Simcenter STAR-CCM+.

Models

The following right-click actions and dialogs are available for models in Simcenter STAR-CCM+ In-cylinder.

Models Right-Click Actions


Object	Right-Click Action
Models	Edit Opens a dialog that allows you to set the in-cylinder time model and optional engine models. See Model Selection Dialog. When no optional models are selected, allows you to simulate the flow and energy in the cylinder and ports of a motorized engine test rig. By default, Simcenter STAR-CCM+ In-cylinder runs a transient moving-mesh simulation of an unfired internal combustion engine. You solve for turbulent flow and for energy in the cylinder and ports of a single cylinder.
Gravity (only if the Gravity engine model is selected)	Edit Opens a dialog that allows you to set the gravitational acceleration vector.
Liquid Film (only if the Liquid Film engine model is selected)	Edit Opens the Liquid Film Dialog. Convert To Single Shell Region In Simcenter STAR-CCM+ In-cylinder Version 2021.2 and before, the Liquid Film engine model used multiple shell regions to solve for the formation and transport of liquid film. From version 2021.3 onwards, to improve performance, Simcenter STAR-CCM+ In-cylinder uses a single shell region instead. For ICE simulations created in previous versions and resumed in the current version, this option allows you to convert the previously created shell regions into a single shell region.
KHRT Breakup (only if the KHRT Breakup engine model is selected)	Edit Opens the KHRT Breakup Dialog.
Reitz-Diwakar Breakup (only if the Reitz-Diwakar Breakup engine model is selected)	Edit Opens the Reitz-Diwakar Breakup Dialog.
Huh Atomization (only if a Secondary Breakup model is selected)	Edit Opens the Huh Atomization Dialog.
ECFM-3Z (only if the ECFM-3Z engine model is selected)	Edit Opens the ECFM-3Z Dialog.
ECFM-CLEH (only if the ECFM-CLEH engine model is selected)	Edit Opens the ECFM-CLEH Dialog.
Specified Burn Rate (only if the Specified Burn Rate engine model is selected)	Edit Opens the Specified Burn Rate Dialog.
Complex Chemistry (only if the Complex Chemistry model is selected)	Edit Opens the Complex Chemistry Dialog.
Turbulent Flame Speed Closure (only if the Turbulent Flame Speed Closure model is selected)	Edit Opens the Turbulent Flame Speed Closure Dialog.
ISSIM Spark-Ignition (only if the ISSIM Spark-Ignition engine model is selected)	Edit Opens the ISSIM Spark-Ignition Dialog.
Auto Ignition (only if the Auto Ignition engine model is selected)	Edit Opens the Auto Ignition Dialog.
Knock (only if the Knock engine model is selected)	Edit Opens the Knock Dialog.
NOx Emission (only if the NOx Emission engine model is selected)	Edit Opens the NOx Emission Dialog.
Soot Sectional (only if the Soot Sectional model is selected)	Edit Opens the Soot Sectional Dialog.
CHT Export (only if the CHT Export engine model is selected)	Edit Opens the CHT Export Dialog.
Remeshing (only if the Remeshing engine model is selected)	Edit Opens the Remeshing Dialog.

Model Selection Dialog


In-Cylinder Time
Implicit Unsteady	When selected, applies the SIMPLE algorithm when solving the discretized system of equations for the fluid continuum.
PISO Unsteady	When selected, applies the PISO algorithm when solving the discretized system of equations for the fluid continuum.


Turbulence
LES	When selected, uses the Large Eddy Simulation technique in which the large scales of the turbulence are directly resolved everywhere in the flow domain, and the small-scale motions are modeled. The WALE Subgrid Scale model computes the subgrid scale viscosity to provide closure to the filtered Navier-Stokes equations. To provide boundary conditions to the solvers for flow and energy that are specific to turbulent boundary layers, the all- $y^{+}$ wall treatment is used. For more information, see Theory Guide: Large Eddy Simulation (LES), Wale Subgrid Scale Model, and Wall Treatment for LES.
RANS	When selected, uses the Reynolds-Averaged Navier-Stokes (RANS) turbulence modeling approach. This approach provides closure relations for the RANS equations, that govern the transport of the mean flow quantities. For more information, see Theory Guide: Reynolds-Averaged Navier-Stokes (RANS) Turbulence Models.


Optional Models
CHT Export	When selected, allows you to calculate and export the cycle-averaged heat transfer coefficients and reference temperatures at the engine walls for use in a subsequent solid thermal analysis in Simcenter STAR-CCM+ or a third-party tool. You can export the cycle-averaged spatial fields to a .csv or .sbd file. The coupling between a Simcenter STAR-CCM+ In-cylinder simulation and a solid thermal analysis can be one-way or two-way. For two-way coupling, the solid thermal analysis supplies the spatial wall temperatures via *.csv file back to the Simcenter STAR-CCM+ In-cylinder simulation. The objective of coupling is typically to determine the thermal evolution in the engine assembly over time periods much longer than one engine cycle. For more information, see File-Based Coupling. To provide an interface for file-based coupling and to account for piston and valve sliding contact heat transfer, Simcenter STAR-CCM+ In-cylinder uses shell regions that represent the engine at BDC position with all valves closed. During the simulation, Simcenter STAR-CCM+ In-cylinder maps the heat transfer coefficients and reference temperatures from the engine walls onto the shells at regular intervals, integrates the mapped data over motion, and averages over one engine cycle. When faces of a shell are not exposed to an engine wall, such as when the liner is not at BDC position, Simcenter STAR-CCM+ In-cylinder allows you to set alternate values for the heat transfer coefficients and reference temperatures. When the simulation completes one engine cycle, Simcenter STAR-CCM+ In-cylinder exports the following cycle-averaged data from the shells, where the cycle-averaging equations described below are applied on a per-cell face basis: CHTExport : Local Heat Transfer Coefficient (W/m^2-K), calculated as: ${\bar{h}}_{l o c a l} = \frac{1}{(θ_{2} - θ_{1})} \int_{θ_{1}}^{θ_{2}} h_{l o c a l} (θ) d θ$ where: $θ$ is the IC engine crank angle. $θ_{1}$ is the crank angle at which the mapping begins. $θ_{2}$ is the crank angle at which the mapping stops. $h_{l o c a l}$ is the local heat transfer coefficient. CHTExport : Local Heat Transfer Reference Temperature (K), calculated as: ${\bar{T}}_{r e f, l o c a l} = \frac{1}{(θ_{2} - θ_{1}) {\bar{h}}_{l o c a l}} \int_{θ_{1}}^{θ_{2}} h_{l o c a l} (θ) T_{r e f, l o c a l} (θ) d θ$ where $T_{r e f, l o c a l}$ is the local heat transfer reference temperature. CHTExport : Specified Y+ Heat Transfer Coefficient (W/m^2-K), calculated as: ${\bar{h}}_{y_{u s e r}^{+}} = \frac{1}{(θ_{2} - θ_{1})} \int_{θ_{1}}^{θ_{2}} h_{y_{u s e r}^{+}} (θ) d θ$ where $h_{y_{u s e r}^{+}}$ is the specified $y^{+}$ heat transfer coefficient. CHTExport : Specified Y+ Heat Transfer Reference Temperature (K), calculated as: ${\bar{T}}_{r e f, y_{u s e r}^{+}} = \frac{1}{(θ_{2} - θ_{1}) {\bar{h}}_{y_{u s e r}^{+}}} \int_{θ_{1}}^{θ_{2}} h_{y_{u s e r}^{+}} (θ) T_{r e f, y_{u s e r}^{+}} (θ) d θ$ where $T_{r e f, y_{u s e r}^{+}}$ is the specified $y^{+}$ heat transfer reference temperature. For more information, see Heat Transfer Field Functions Reference. You can edit the properties of the CHT Export model, using the Models > CHT Export node.
Combustion	When selected, allows you to simulate the combustion process in the engine cylinder initiated by spark ignition. For more information, see Theory Guide—Internal Combustion Engines.
Gravity	When selected, accounts for the effect of gravitational acceleration on the gas and the fuel inside the engine. For more information, see Theory Guide—Gravity. By default, the gravitational acceleration vector has a magnitude of 9.81m/s² and points in negative Z-direction of the Laboratory coordinate system. You can edit the vector using the corresponding Models > Gravity node.
Injection (Automatically selects the Polynomial Fuel Density model.)	When selected, allows you to simulate the injection of a liquid fuel and the subsequent evaporation and mixing process. You solve for the transport of representative parcels of the liquid fuel droplets in a Lagrangian framework. For more information, see Theory Guide—Lagrangian Multiphase Flow.
Real Gas	By default, Simcenter STAR-CCM+ In-cylinder calculates the gas density using the ideal gas equation, see Eqn. (671). However, at high pressure and low temperature, the p-v-T behavior of real gases deviates from that predicted by the ideal gas equation. This change of behavior results from the molecules of the gas taking up a significant portion of the total volume as the gas density increases. In addition, intermolecular attractive forces become increasingly important. When the Real Gas model is selected, Simcenter STAR-CCM+ In-cylinder takes into account non-ideal behavior using the Redlich-Kwong equation as given by Eqn. (680).
Liquid Film (only if the Injection engine model is selected)	When selected, accounts for the formation and transport of a thin film of fuel on the engine walls. Simcenter STAR-CCM+ In-cylinder simulates fluid accumulation on walls through droplet impingement: droplets carried along in the gas impinge on walls to form a liquid layer. The Bai-Gosman model predicts the outcomes of fuel droplets impacting the walls depending on different impingement regimes. The fluid film can reduce in thickness or be removed through the following mechanisms: Wave stripping where droplets are stripped due to wave instabilities in the fluid film. Edge stripping where droplets are stripped when the fluid film flows over a sharp edge. Evaporation Boiling The surface tension for the phase interactions between the liquid film and the fuel droplets and between the liquid film and the gas phase is calculated using the Mixture Method for Surface Tension. For fuel components selected from ecfmProp material database, the tabular temperature-dependent surface tension of each component is interpolated using a field function. You solve for the transport of the liquid film in a Eulerian framework. For more information, see Theory Guide—Fluid Film and Theory Guide—Bai-Gosman Wall Impingement.
Modified UNIFAC (only if the Injection engine model is selected)	By default, Simcenter STAR-CCM+ In-cylinder obtains the vapor pressure at the liquid surface of the fuel droplets or the liquid film using Raoult's Law, which assumes an ideal mixture with a similar molecular structure for the fuel components. For more information, see Theory Guide—Raoult's Law. When the Modified UNIFAC model is selected, it allows you to obtain the vapor pressure at the liquid surface for complex mixtures, where the molecular structure of components is very different. This model categorizes a component by its structural functional groups, and assumes that certain thermodynamic properties can be calculated by summing the group contributions. For more information, see Theory Guide—Modified UNIFAC.
CO Emissions (only if the ECFM-CLEH engine model is selected)	When selected, accounts for the production of CO due to incomplete combustion. For more information, see Theory Guide—CO Emissions in ECFM. You can edit the properties of the CO Emission model using the Models > ECFM-CLEH node.
Knock (only if the Spark Ignition engine model is selected)	When selected, accounts for the spontaneous ignition of the combustible mixture, without an external source of ignition. For more information, see Theory Guide—ECFM TKI Auto-Ignition. You can edit the properties of the Knock model using the Models > Knock node.
NOx Emission (only if an ECFM combustion model is selected)	When selected, accounts for the formation of nitric oxide during combustion. Simcenter STAR-CCM+ In-cylinder uses the Nitrogen Oxide Relaxation Approach (NORA), which is based on the tabulation of equilibrium values of three NOx species and their relaxation times following perturbation. NORA makes a distinction between NO, NO2, and N2O. These products are represented separately in the model. The generation of NORA tabular libraries is based on complex chemistry as well as on thermal considerations. Two main chemical mechanism are employed: one for the NO-NO2 coupled and the other for N2O. For more information, see Theory Guide—NOx Relaxation Approach (NORA). You can edit the properties of the NOx Emission model using the corresponding Models > NOx Emission node.
Fuel Saturation Distribution (only if an ECFM combustion model is selected together with Auto Ignition or Knock)	Before fuel droplets evaporate and mix homogeneously throughout a cell, the evaporated fuel is initially located in close proximity to the fuel droplets. The Fuel Saturation Distribution model uses a fuel mass fraction profile to account for the initially uneven distribution of fuel mass fraction in a cell. For more information, see Theory Guide—Fuel Saturation Distribution.
Soot Emissions (only if an ECFM combustion model or the Complex Chemistry combustion model is selected) Selecting this model automatically selects the Soot Sectional model.	When selected, allows you to account for the formation of carbonaceous particles, called soot, during combustion. These particulates are identified in flames and fires as yellow luminescence. In gas turbines, internal combustion engines and other practical combustion devices, the formation of soot is mostly a product of incomplete combustion. For more information, see Theory Guide—Soot.
Remeshing	When selected, triggers remeshing when the mesh quality drops below the specified Re-mesh Criteria. In conjunction with the morpher, which redistributes the mesh vertices in response to the movement of the piston and the valves, the remeshing model operates by predicting what the mesh quality would be if the morpher were applied on the current mesh. If the mesh quality falls below any of the specified criteria, the model triggers a remesh instead. This mode of operation is known as predictive morphing and allows you to avoid negative volume cells or highly skewed cells that would otherwise prevent a successful simulation. You can save meshes within a cycle to a specified output directory and reuse them in the next cycle, which avoids remeshing time. You can set up this Mesh Reuse using the corresponding Models > Remeshing node.


K-Epsilon Turbulence (only if the RANS engine model is selected)
RNG K-Epsilon	When selected, uses the RNG K-Epsilon turbulence model with a two-layer all- $y^{+}$ wall treatment to provide closure relations for the RANS equations. For more information, see Theory Guide: RNG K-Epsilon Model and Wall Treatment for RANS.
Realizable K-Epsilon Two-Layer	When selected, uses the Realizable K-Epsilon Two-Layer turbulence model with an all- $y^{+}$ wall treatment to provide closure relations for the RANS equations. For more information, see Theory Guide: K-Epsilon Model and Wall Treatment for RANS.


Fuel Density (only if the Injection engine model is selected)
Constant Fuel Density	When selected, assumes that the fuel density is invariant throughout the continuum. For more information, see Theory Guide—Constant Density.
Polynomial Fuel Density	When selected, calculates the fuel density as a function of temperature in the form of a polynomial. For more information, see Theory Guide —Polynomial Density.


Secondary Breakup (only if the Injection engine model is selected)
KHRT Breakup	When selected, accounts for Secondary Breakup of the fuel droplets using the KHRT Breakup model. The KHRT Breakup model combines two submodels, one based on Kelvin-Helmholtz (KH) theory and the other based on Rayleigh-Taylor (RT) theory. Both breakup submodels consider the growth of instabilities on a droplet and provide expressions for their wavelength and frequency. Kelvin-Helmholtz instabilities are due to the slip velocity of the droplet, which eventually shears small child droplets off the parent, corresponding to the stripping regime. Rayleigh-Taylor instabilities are due to the acceleration of the droplet and tend to shatter the droplet completely, corresponding to the catastrophic regime. The KH and RT submodels compete: instabilities due to both can grow simultaneously; if they grow for long enough, breakup occurs due to the RT instabilities. Otherwise KH breakup occurs. For more information, see Theory Guide—KHRT Breakup Model. You can edit the properties for KH breakup and RT breakup using the corresponding Models > KHRT Breakup node.
Reitz-Diwakar Breakup	When selected, accounts for Secondary Breakup of the fuel droplets using the Reitz-Diwakar Breakup model. The Reitz-Diwakar breakup model is based on observed length- and time-scales of droplet breakup. It assumes that breakup occurs in one of two possible modes: Bag breakup—the non-uniform pressure field around the droplet causes it to expand in the low-pressure wake region and eventually disintegrate when surface tension forces are overcome Stripping breakup—liquid is sheared or stripped from the droplet surface For more information, see Theory Guide—Reitz-Diwakar Breakup Model. You can edit the properties for both breakup modes using the corresponding Models > Reitz-Diwakar Breakup node.


Atomization (only if a Secondary Breakup model is selected)
Huh Atomization	The Huh Atomization model is a primary atomization model that allows you to simulate the disintegration process of a liquid jet exiting from a hole-type injector at high speed. This model estimates the initial perturbations from an analysis of the flow through the nozzle and then uses established wave growth theory, together with other hypotheses, to represent the atomization process. The Huh model assumes an initial droplet size equal to the nozzle diameter; droplet velocity and subsequent breakup is modeled as described in the formulation, see Theory Guide—Huh Model.


Combustion Model (only if the Combustion engine model is selected)
Complex Chemistry	The Complex Chemistry model allows you to introduce detailed chemistry information to your ICE simulation. This combustion model can solve thousands of reactions among hundreds of species. The Complex Chemistry model requires detailed reaction mechanism information about species, reactions, thermodynamics, and transport properties. You supply these details using complex chemistry definition files in the Chemkin format. In Simcenter STAR-CCM+ In-cylinder, detailed Complex Chemistry is solved using a stiff CVODE ODE (Ordinary Differential Equation) solver to integrate the chemical source terms. For this reason, the Complex Chemistry model can handle stiff reaction systems (reaction systems with a wide range of reaction time scales). To consider the turbulence effects on combustion, Simcenter STAR-CCM+ In-cylinder provides the Turbulent Flame Speed Closure (TFC) model and the Laminar Flame Concept (LFC) model. For more information, see Theory Guide—Complex Chemistry.
ECFM-3Z	The Extended Coherent Flame Model Three Zone (ECFM-3Z) is a general-purpose combustion model that is capable of simulating the complex mechanisms of turbulent mixing, flame propagation, and diffusion combustion that characterize modern internal combustion engines. 3Z stands for three zones of mixing: the unmixed fuel zone the mixed gases zone the unmixed air plus exhaust gas recirculation (EGR) zone The three zones are too small to be resolved by the mesh and are therefore modelled as sub-grid quantities. The mixed zone is the result of turbulent mixing and molecular mixing between gases in the other two zones, and is where combustion takes place. For more information, see Theory Guide—ECFM-3Z. You can edit the properties of the ECFM-3Z model using the Models > ECFM-3Z node.
ECFM-CLEH Selecting this combustion model automatically selects the following engine models: CO Emissions	The Extended Coherent Flame Model with Combustion Limited by Equilibrium Enthalpy (ECFM-CLEH) is a combustion model in which burning rates are limited by a thermodynamic equilibrium given by complex chemistry. In this model, the computational cells are split into four zones: the unmixed zone the premixed zone the diffusion zone the post-oxidation zone Combustion can occur only in the premixed and diffusion zones and then in the post-oxidation zone. As the premixed combustion progresses, fuel diffusion is generated in the burnt gases area and is then burnt. Post-oxidation combustion can then also take place when specific thermodynamic conditions are met and fuel mixing is sufficiently homogenous. For more information, see Theory Guide—ECFM-CLEH. You can edit the properties of the ECFM-CLEH model using the Models > ECFM-CLEH node.
Specified Burn Rate	The Specified Burn Rate model allows you to pre-specify the fuel burning rate through an analytic function—the Wiebe function. As a result, you can avoid the calculation of chemical reaction rates based on complicated physical and chemical processes. This cost-effective approach is frequently used to obtain quick, first-cut solutions to multi-cycle CFD problems. In such problems, the main interest is in the effects produced by the existence of combustion rather than the combustion process itself. Examples of typical applications are: Evaluation of engine response to different burning rates in engine performance optimization studies. This includes calculation of the momentum/turbulence field, dynamic thermal field and species and emission product fields. Rapid generation of accurate initial conditions for use with other, more detailed combustion models Emission studies undertaken without including a detailed combustion model Engine port flow predictions when the exhaust valve opens after combustion Thermal analysis of cylindrical coolant jacket flow under combustion conditions For more information, see Theory Guide—Specified Burn Rate. You can edit the properties of the Specified Burn Rate model using the Models > Specified Burn Rate node.


Chemistry Interactions (only if the Complex Chemistry combustion model is selected)
Laminar Flame Concept	The Laminar Flame Concept (LFC) model considers the turbulence effects on combustion implicitly through the increased turbulent diffusivity that is provided by the turbulence model. For more information, see Theory Guide—Complex Chemistry.
Turbulent Flame Speed Closure	The Turbulent Flame Speed Closure (TFC) model uses the concept of turbulent flame speed to model the turbulent-chemistry interactions. This model provides the following choice of correlations for turbulent flame speed: Zimont, the most widely used option for constant pressure combustion simulations Peters, commonly for internal combustion engines You can edit the properties of the TFC model using the Models > Turbulent Flame Speed Closure node. For more information, see Theory Guide—Turbulent Flame Speed.


Ignition Model (only if an ECFM combustion model is selected)
Spark Ignition (not for cylinder sector models)	Spark ignition models grow a spark from a small kernel until it is sufficiently large enough for the combustion model to take over the flame propagation.
Auto Ignition	The Auto Ignition model accounts for the spontaneous ignition of the combustible mixture, without an external source of ignition. For more information, see Theory Guide—ECFM TKI Auto-Ignition. You can edit the properties of the Auto Ignition model using the Models > Auto Ignition node.


Spark Ignition Model (only if the Spark Ignition engine model is selected)
FI Spark-Ignition	The FI Spark Ignition model is a basic spark ignition model that comprises two stages: a first stage that models the time delay between the spark and the appearance of the flame surface a second stage that takes care of the actual deployment of the flame surface in the mean gases For more information, see Theory Guide—FI Spark Ignition.
ISSIM Spark-Ignition	The Imposed Stretch Spark Ignition Model (ISSIM) is a Eulerian spark-ignition model for 3D RANS simulations of internal combustion engines. The spherical kernel equation is used directly in the Eulerian transport equations—allowing a description of all local phenomena. The use of a flame surface density equation allows the simulation of multi-spark ignition and of the flame holder effect. Both flame growth and wrinkling are modelled via the ECFM equation. Assuming an inductive ignition system, the ISSIM model provides the amount of energy transferred to the gas during the glow phase as well as the evolution of the spark, which is then convected and wrinkled by the flow. At the instant of electrical breakdown, an initial burnt gas profile is created on the 3D CFD mesh. From then on, the reaction rate is directly controlled by the flame surface density (FSD) equation. A number of adjustments are then made to this equation so that it can correctly describe the combustion evolution during the early ignition stage. For more information, see Theory Guide—ISSIM Spark Ignition. You can edit the properties of the ISSIM Spark-Ignition model using the Models > ISSIM Spark-Ignition node.


Soot Emissions Model (only if the Soot Emissions engine model is selected)
Soot Sectional	The soot sectional method is based on a description of sections containing soot particles of equal volume, allowing a volume-based discretization of particle sizes together with conservation of the soot number density and mass. For more information, see Theory Guide—Soot Sections. You can edit the properties of the Soot Sectional model using the Models > Soot Sectional node.

Liquid Film Dialog


Liquid Film
Liquid Film Surfaces	After the creation of cylinder and valves, allows you to specify the Engine Part Surfaces for which you want to solve for the formation and transport of liquid film.

KHRT Breakup Dialog


KH Breakup
Length Coefficient (B0)	Specifies the KH length coefficient, see Eqn. (3099).
Time Coefficient (B1)	Specifies the KH time coefficient, see Eqn. (3098).
Normal Velocity Coefficient (A1)	Specifies the normal velocity coefficient for child parcels, see Eqn. (3101).


RT Breakup
Length Coefficient (C3)	Specifies the RT length coefficient, see Eqn. (3104).
Time Coefficient (Ctau)	Specifies the RT time coefficient, see Eqn. (3103).

Reitz-Diwakar Breakup Dialog


Bag Breakup
Minimum Weber Number (WeCrit)	Specifies the minimum Weber number for breakup, see Eqn. (3106).
Time-scale coefficient (Cb2)	Specifies the bag breakup time-scale coefficient, see Eqn. (3107).


Stripping Breakup
Onset coefficient (Cs1)	Specifies the coefficient prescribing the onset of stripping breakup, see Eqn. (3108).
Time-scale coefficient (Cs2)	Specifies the stripping breakup time-scale coefficient, see Eqn. (3109).

Huh Atomization Dialog


Model Parameters
Atomization Length Scale Coefficient (C1)	Specifies the atomization length scale coefficient $C_{1}$ used to define the wavenumber $κ$ in Eqn. (3085).
Wave Length Scale Coefficient (C2)	Specifies the wave length scale coefficient $C_{2}$ used to define the wavenumber $κ$ in Eqn. (3085).
Spontaneous Time Scale Coefficient (C3)	Specifies the spontaneous time scale coefficient $C_{3}$ in Eqn. (3086).
Exponential Time Scale Coefficient (C4)	Specifies the exponential time scale coefficient $C_{4}$ in Eqn. (3086).
Turbulence Time Scale Coefficient (CA1)	Specifies the turbulence time scale coefficient $C_{a 1}$ in Eqn. (3083) and Eqn. (3084).
Turbulence Length Scale Coefficient (CA2)	Specifies the turbulence length scale coefficient $C_{a 2}$ in Eqn. (3083).
Breakup Rate Coefficient (KA)	Specifies the droplet breakup rate coefficient $K_{A}$ in Eqn. (3087).
Normal Velocity Coefficient	Controls the radial diffusion of the spray; $K_{3}$ in Eqn. (3118). The larger it is, the more rapid the radial diffusion of the spray.
Critical Weber Number	The critical Weber number ${W e}_{c r}$ . For the Huh model, the Weber number is given by Eqn. (3079). If $W e < {W e}_{c r}$ , the injected parcel bypasses the primary atomization process and proceeds directly to the secondary breakup process.

ECFM-3Z Dialog


ECFM Model Time Setup
ECFM Start Time	Specifies the time at which ECFM combustion begins, in s or in the cyclic time unit degCA.
Combustion Reset Time	When regressing the progress variable back to 0 in multiple-cycle simulations, the mass fractions of species $i$ and their tracers are changed at each time-step according to Eqn. (3932) until this time at which combustion reset is complete. By default, the combustion reset time is automatically set to 5 degCA before intake valve opening (IVO).

ECFM-CLEH Dialog


ECFM Model Time Setup
ECFM Start Time	As for ECFM-3Z Dialog.
Combustion Reset Time	As for ECFM-3Z Dialog.


ECFM-CLEH Parameters
Fuel	Specifies the injected fuel type. The following options are available: Gasoline Diesel Custom For Gasoline and Diesel, Simcenter STAR-CCM+ In-cylinder automatically sets values for the Premix Zone Transfer Coefficient and the Premix Transfer Burning Rate Limit (/s) that are suitable for these fuels.
Premix Zone Transfer Coefficient (read-only for Gasoline and Diesel)	Specifies the proportion of premixed fuel that is added to the premixed chemical equilibrium limit. When the chemical equilibrium limit is reached in the premixed zone, it is transferred to the diffusion zone or to the post-oxidation zone.
Premix Transfer Burning Rate Limit (/s) (read-only for Gasoline and Diesel)	Specifies the normalized premixed zone reaction rate limit for which premixed fuel is transferred to the diffusion zone or to the post-oxidation zone. This applies only if the normalized premixed zone reaction rate is smaller than the premix transfer burning rate limit.


ECFM Equilibrium Table
ECFM Equilibrium Table	Specifies the library table for calulating the equilibrium fuel mass fractions for premixed and diffusion combustion. The supported file format is *.tbl. A variety of ECFM-CLEH equilibrium tables are available to download from the Siemens Support Center: The libraries are located within the Products > Simcenter STAR-CCM+ area, in the Downloads section. When a version is selected in the Major Releases panel, the Linux or Windows folder contains the In-Cylinder folder, in which the available libraries are found. For more information, see Theory Guide—ECFM-CLEH Combustion Library Tables.


CO Emissions
Pollutant Equilibrium Temperature Offset	Specifies a variation of temperature added to the chemical equilibrium for pollutant calculation.
Temperature of CO Model Cut Off	Specifies the burnt temperature below which the CO Emission model is frozen.

Specified Burn Rate Dialog


Specified Burn Rate Settings
Combustion Reset Time	For a multi-cycle run, after the completion of combustion and before the exhaust valve opening (EVO), resets the progress variable from 1.0 (burnt state) to 0.0 (unburnt/EGR). By default, the combustion reset time is automatically set to 5 degCA before EVO.
Wiebe Settings	Exponent Specifies $n$ in Eqn. (4053), in the range ]0, 100[. Timing at 50% Fuel Burned Specifies the time at which 50% of the fuel is burned. Duration of 10-90% Fuel Burned Specifies the time duration from the time at which 10% of the fuel is burnt until the time at which 90% of the fuel is burnt, in the range ]0, cycle length[.

Complex Chemistry Dialog


Chemkin Files
Import Chemkin Files...	Opens the Import Chemkin Files dialog, where you specify the following files in *.chm format: Chemical Mechanism File This file provides a list of the species and their reaction rates. Thermodynamic Properties File This file provides the specific heat polynomial coefficients, as well as the heat of formation, standard state entropy, and elemental composition for all species in the mechanism. Import Transport Properties File When On, allows you to import a transport properties file. Molecular transport properties are particularly important for laminar flame simulations. Transport Properties File This file provides the Lennard Jones properties: dipole, rotation, polarization, molecule type, characteristic energy, and characteristic length. For more information, see Reaction Mechanism Formats.


Approximation Options (only available if the Turbulent Flame Speed Closure model is selected)
Relax to Chemical Equilibrium	When On, assumes that the chemical composition relaxes to the local equilibrium composition at a time scale that is determined by flow and chemistry time scales. For more information, see Theory Guide—Complex Chemistry.


Relax to Chemical Equilibrium (only available if the Relax to Chemical Equilibrium option is selected)
Timescale Constant	Sets $c_{t}$ in Eqn. (3417) which allows you to control the relaxation time of the reaction behind the flame front by scaling the Kolmogorov timescale $τ_{k}$ .


Chemistry Acceleration
Clustering	When On, reduces the computational expense of complex chemistry calculations by averaging together cells with similar chemical compositions, integrating the reduced ODE (Ordinary Differential Equation) set, and then interpolating the clusters back to the cells. Clustering usually provides a substantial speed-up as the number of clusters is less than the number of cells in the simulation. Since the number of clusters increases much slower than the number of cells, clustering performance improves with mesh size. For more information, see Theory Guide—Clustering.
Dynamic Mechanism Reduction (not available if the Relax to Chemical Equilibrium option is selected)	When On, allows to solve for a reduced number of species that are taken from the full chemical mechanism that is imported. The mechanism is reduced dynamically—in every cell at every time-step or iteration. Solving for fewer species reduces computational time, however, accuracy is also reduced. Dynamic Mechanism Reduction is based on the Directed Relation Graph (DRG) algorithm [755] where species that do not change any other species substantially over the reaction time-step are eliminated from the mechanism. Error Tolerance The lower the number, the closer the solution is to that of the full chemical mechanism—less species are removed from the mechanism. Higher values exclude a greater number of species from the solution, which is therefore less accurate. For more information, see Theory Guide—Dynamic Mechanism Reduction.


Chemistry Solver Tolerances (not available if the Relax to Chemical Equilibrium option is selected)
Absolute Tolerance	The Complex Chemistry model uses the CVODE ODE (Ordinary Differential Equation) solver to integrate the chemistry over an iteration or time-step. This property specifies the absolute error tolerance for each ODE step in the CVODE ODE solver. The solver makes sure that the error is less than the relative tolerance multiplied by the quantity that is being integrated, plus the absolute tolerance.
Relative Tolerance	Specifies the relative error tolerance for each ODE step in the CVODE ODE solver. The solver makes sure that the error is less than the relative tolerance multiplied by the quantity that is being integrated, plus the absolute tolerance.

Turbulent Flame Speed Closure Dialog


Turbulent Flame Speed Closure
Turbulent Flame Speed Closure	Flame Speed Scaling Factor Specifies a multiplier of the turbulent flame speed which allows you to increase the turbulent flame speed.
Laminar Flame Speed	Provides the following options for controlling the unstrained laminar flame speed: Gulder: uses the Gülder laminar flame speed correlation, see Eqn. (3579). Metghalchi: uses the Metghalchi laminar flame speed correlation, see Eqn. (3573). Fuel Specifies the fuel name, which determines the values for the fuel-dependent model coefficients. The following options are available: Methane (only for Gulder) Propane Methanol Ethanol (only for Gulder) Iso-Octane
Turbulent Flame Speed	Provides the following methods for calculating the turbulent flame speed source term: Zimont: selects the Zimont method, see Eqn. (3580). Peters: selects the Peters method, see Eqn. (3585).

ISSIM Spark-Ignition Dialog


Physics
Solve 0D Equation For Flame Kernel Radius	When On, solves a zero-dimensional equation for flame kernel radius given by Eqn. (3990). When Off, the flame is resolved on the mesh from the beginning of ignition.
Initial Burnt Mass	Specifies how the initial mass of burnt products that is deposited after the electric arc $m_{b}^{i g n}$ is determined. The following options are available: Minimum Critical Burning Mass: calculates $m_{b}^{i g n}$ using the first option in [eqn_link]. From Actual Spark Energy Released: calculates $m_{b}^{i g n}$ using the second option in [eqn_link]. From Fixed Plasma Temperature: calculates $m_{b}^{i g n}$ using the third option in [eqn_link].
LFS Sphere Coefficient	Specifies the coefficient for the effective Laminar Flame Speed sphere of influence size, see ${S p}_{S L}$ in Eqn. (4000).
Initial Burnt Mass Coefficient	Specifies the multiplication constant for the initial ignition burnt mass, see $K_{m b i g n}$ in [eqn_link].
Spark Energy Dilution Coefficient	Specifies the spark energy dilution proportional coefficient, see $K_{d i l}$ in Eqn. (3978).
Laminar Flame Speed Correction	Maximum Unburnt Temperature Specifies the maximum acceptable temperature for laminar flame speed evaluation, see $T_{u}^{\max}$ in Eqn. (4003).
Flame Kernel Propagation (only if Solve 0D Equation For Flame Kernel Radius is On)	Maximum Wrinkling Coefficient Specifies the maximum flame surface convolution coefficient, see $K_{x m}$ in Eqn. (3994). Wrinkling Production Coefficient Specifies the coefficient for the turbulent wrinkling prodction term, see $K_{x p}$ in Eqn. (3993). Transition Ratio Specifies the ratio of flame kernel transition radius to turbulent length scale, see $T_{r}$ in Eqn. (3995). Maximum Transition Radius Specifies the maximum value of the falme kernel transition radius, see $R_{k}^{L}$ in Eqn. (3995).
Laminar Flame Speed (only if the Complex Chemistry and the Laminar Flame Concept engine models are selected )	Provides the following options for controlling the unstrained laminar flame speed: Gulder—uses the Gülder laminar flame speed correlation, see Eqn. (3579). Metghalchi—uses the Metghalchi laminar flame speed correlation, see Eqn. (3573). Fuel Specifies the fuel name, which determines the values for the fuel-dependent model coefficients. The following options are available: Methane (only for Gulder) Propane Methanol Ethanol (only for Gulder) Iso-Octane

Auto Ignition Dialog


TKI Table
TKI Table	Specifies the library table for calulating the auto-ignition delay and the auto-ignition burn rates. The supported file format is *.tbl. A number of Tabulated Kinetics for Ignition (TKI) tables for a variety of fuels are available to download from the Siemens Support Center. Tabulated Kinetics of Ignition with Probability Density Function (PDF) is supported. You can locate the libraries on the Siemens Support Center: The libraries are located within the Products > Simcenter STAR-CCM+ area, in the Downloads section. When a version is selected in the Major Releases panel, the Linux or Windows folder contains the In-Cylinder folder, in which the available libraries are found.

Knock Dialog


TKI Parameters
Delay Factor	Specifies a multiplier factor for the auto-ignition delay provided by the TKI table.
Burn Rate Factor	Specifies a multiplier factor for the auto-ignition burn rate provided by the TKI table.
Dual Zone TKI Model Option	When On, makes use of a progress variable that is different from the flame propagation, in order to remedy the heat releases at knock onset.


TKI Table
TKI Table	See Auto Ignition Dialog.

NOx Emission Dialog


NORA Parameters
Cut Off Temperature	Specifies the temperature below which reactions are not evaluated.
Input Fuel Enthalpy Correction	Specifies the fuel enthalpy correction for NORA libraries. Modifies the enthalpy contribution of the fuel which is used to enter the NORA libraries. Set this value if you want to adjust the level of NOx globally. Increasing this value increases the level of NOx and the other way around.


NORA Table
NORA Table	Specifies the table of equilibrium values for the three NOx species and their relaxation times following a perturbation. The supported file format is *.tbl. A generic NORA table that is almost independent of the fuel is available to download from the Siemens Support Center: The table is located within the Products > Simcenter STAR-CCM+ area, in the Downloads section. When a version is selected in the Major Releases panel, the Linux or Windows folder contains the In-Cylinder folder, in which the table is found. For more information, see Theory Guide—NOx Relaxation Approach (NORA).

Soot Sectional Dialog


Soot Properties
Nucleation	Particle nucleation (or particle inception) is an important first step in process of soot formation. Particle nucleation results in generation of the smallest sized soot particles. Nucleation is usually modeled as the coalescence of two polycyclic aromatic hydrocarbons (PAH) species (soot precursors) into a soot particle. The following options are available: Single PAH Species (C16H10): for the single PAH species nucleation option, the soot precursor for inception is assumed to be pyrene (A4). If A4 is absent from the mechanism, an isomer with same chemical composition (C16H10) is used—such as A3R5. The nucleation rate for the moments is given Eqn. (3679) and Eqn. (3680). C2H2: if the chemical mechanism used does not include A4 species, Simcenter STAR-CCM+ In-cylinder allows acetylene (C2H2) to be used as a soot precursor for nucleation. The expression for nucleation when using C2H2 as a soot precursor is given by Eqn. (3682). Multi PAH Species (only if the Complex Chemistry model is selected): selects the PAH precursor species from those that are present in the chemical mechanism. Simcenter STAR-CCM+ In-cylinder recognises the chemical symbols of the PAH precursor species as described within the table for Multi PAH Species Nucleation.
Steric Factor Alpha	Specifies $α$ in Eqn. (3706), in the range [0, 1]. The steric factor desribes the fraction of reactive sites on the surface of the soot particle that are available for soot growth or oxidation reactions.
Scale	Surface-growth Scales surface growth ${\tilde{Ω}}_{i, s g}$ in Eqn. (3717). Nucleation Scales nucleation ${\tilde{Ω}}_{i, n u c}$ in Eqn. (3717). Oxidation Scales oxidation ${\tilde{Ω}}_{i, o x}$ in Eqn. (3717). Coagulation Scales coagulation ${\tilde{Ω}}_{i, c o a g}$ in Eqn. (3717).
Sectional	Number of Sections Number of discrete sections in the particle size distribution function (PSDF). Maximum Soot Diameter Maximum diameter to which the soot particle grows.


Soot Table (only if an ECFM combustion model is selected)
File Name	Displays the path and the name of the soot table. You can create soot tables using DARS. Import File Displays the Open dialog in which you locate the required soot table and click Open.


PAH Species Component (only if the Multi PAH Species option is selected)
Lists the PAH precursor species that Simcenter STAR-CCM+ In-cylinder selected from those that are present in the chemical mechanism.

CHT Export Dialog


CHT Export Setup
Offset From Start Angle to Begin	Specifies an offset from the specified Start Angle at which the first data mapping is performed. This property allows you to reduce the influence of initialization.
Delta Angle	Specifies the mapping interval at which the heat transfer data are mapped from the engine walls onto the shell regions.
Sliding Window	Specifies the sliding window for subsequent cycle-averaging runs. The specified value must be integer divisible by the cycle length.
Export Option	Specifies the export file format. The following options are available: SBD: exports a Simcenter STAR-CCM+ Boundary Data (.sbd) file that contains the cycle-averaged heat transfer data as well as shell mesh information. For more information, see Working with the Simcenter STAR-CCM+ Boundary Data (.sbd) Format. XYZ Internal Table: exports a .csv file that contains the cycle-averaged heat transfer data as well as the coordinates of the shell face centroids in the Laboratory coordinate system. The export file is written to your current working directory.
User Specified y+	Specifies the $y^{+}$ -value for the calculation of the Specified y+ Heat Transfer Coefficient. See $y_{u s e r}^{+}$ in Eqn. (1666).
Output Separate Files	When Off, exports the cycle-averaged heat transfer data to a single file. The name of the file is given as: [simulation name]_[crank angle].[format] where: [simulation name] is the name of the *.sim file. [crank angle] is the crank angle position at which the data is exported, in deg. [format] is the file format—sbd or csv. When On, exports the cycle-averaged heat transfer data to individual files—one for each valve, one for the piston, and one for the remaining surfaces. For an engine with one intake valve and one exhaust valve, the names of the files are given as: [simulation name]_IntakeValve_[crank angle].[format] [simulation name]_ExhaustValve_[crank angle].[format] [simulation name]_Piston_[crank angle].[format] [simulation name]_FixedAndLiner_[crank angle].[format]
Alternate Values	For faces of shell regions (valves, piston, plenums, and static surfaces) that are not exposed to an engine wall, specifies alternate values for the following heat transfer coefficients and reference temperatures: Local Heat Transfer Coefficient Local Heat Transfer Reference Temperature Specified Y+ Heat Transfer Coefficient Specified Y+ Heat Transfer Reference Temperature See Heat Transfer Field Functions Reference.
Example: For the simulation of a four-stroke engine with a cycle length of 720 deg and a Start Angle of 330 deg, consider the following CHT Export settings: Offset From Start Angle to Begin: 2 deg Delta Angle: 1 deg Sliding Window: 30 deg Export Option: SBD With these settings, the simulation starts at 330 deg, starts mapping at 332 deg, and continues mapping every 1 deg until it reaches 1052 deg. The simulation stops and exports the cycle-averaged mapped data to an .sbd file. When you resume Simcenter STAR-CCM+ In-cylinder, the simulation runs for another 30 deg while mapping every 1 deg. At 1082 deg, the simulation stops again and exports another .sbd file that contains the cycle-averaged data of the last 720 deg. Note that when you use the CHT Export model, the specified Duration is not taken into account.

Remeshing Dialog


Remeshing Settings
Reuse Meshes	When On, saves meshes within a cycle to a specified output directory and reuses them in the next cycle, which avoids remeshing time. The meshes are saved in Simcenter STAR-CCM+ CCM file format as: [mesh file base name]_[mesh station identifier].ccm where: [mesh file base name] is the specified Mesh File Base Name. [mesh station identifier] is the cycle wrapped crank angle in deg (0 to cycle length), which identifies the geometry position of the moving piston and valves. The crank angle value is rounded to 3 decimal places. Example: RepeatingMesh_245.315.ccm Mesh reuse is particularly useful for multi-cycle simulations. CCM Output Directory Specifies the absolute or relative path to the directory where the meshes are saved. You are advised to use a dedicated directory for each simulation run. Mesh File Base Name Specifies the base name of the mesh files. Clear Mesh Files When On, allows you to clear saved mesh files from the specified output directory. Clear Internal Re-use Table When On, allows you to clear the state of mesh reuse, which is internally stored as a table. Activate this option when you want to rerun the simulation with different mesh settings or when you move a copy of the simulation file to another directory to run a different engine configuration.