在Star-CCM+中实现UDF并引用场数据和网格数据

Star-CCM+中的用户自定义函数(UDF)允许用户通过Java或C/C++编程扩展软件功能。下面我将详细介绍如何实现UDF并引用模拟数据。

1. UDF基础实现方法

1.1 创建UDF的步骤

在Star-CCM+中，右键点击"工具" → “用户函数” → “新建”
选择Java或C/C++作为编程语言
为UDF命名并选择适当的模板
编写代码并编译
将UDF分配给适当的场函数或边界条件

1.2 Java UDF基本结构示例

import star.common.*;
import star.base.neo.*;
import star.meshing.*;public class MyUDF extends StarMacro {@Overridepublic void execute() {// 获取当前模拟会话Simulation simulation = getActiveSimulation();// 获取网格和场数据MeshPart meshPart = simulation.get(SimulationPartManager.class).getMeshPart();ScalarField temperatureField = simulation.getFieldManager().getField("Temperature");// 在这里处理数据...}
}

2. 引用场数据和网格数据的示例

2.1 访问标量场数据示例

import star.common.*;
import star.base.neo.*;
import star.flow.*;public class TemperatureUDF extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 获取温度场ScalarField temperature = (ScalarField) simulation.getFieldManager().getField("Temperature");// 获取当前迭代的场数据FieldData fieldData = temperature.getFieldData();// 遍历所有单元获取温度值Region region = simulation.getRegionManager().getRegion("Region");MeshPart meshPart = region.getMeshPart();for (PartSurface surface : meshPart.getPartSurfaces()) {for (Face face : surface.getFaces()) {double tempValue = fieldData.getDouble(face);// 处理温度数据...}}}
}

2.2 访问矢量场和网格几何数据示例

import star.common.*;
import star.base.neo.*;
import star.meshing.*;
import star.flow.*;public class VelocityUDF extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 获取速度场VectorField velocityField = (VectorField) simulation.getFieldManager().getField("Velocity");FieldData velocityData = velocityField.getFieldData();// 获取网格几何数据Region region = simulation.getRegionManager().getRegion("Region");MeshPart meshPart = region.getMeshPart();// 遍历单元计算速度大小for (Cell cell : meshPart.getCells()) {NeoVector velocity = velocityData.getVector(cell);double speed = Math.sqrt(velocity.x()*velocity.x() + velocity.y()*velocity.y() + velocity.z()*velocity.z());// 获取单元中心坐标DoubleVector center = cell.getCenter();double x = center.get(0);double y = center.get(1);double z = center.get(2);// 处理数据...}}
}

2.3 修改场数据示例

import star.common.*;
import star.base.neo.*;
import star.flow.*;public class ModifyFieldUDF extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 获取并修改压力场ScalarField pressureField = (ScalarField) simulation.getFieldManager().getField("Pressure");FieldData pressureData = pressureField.getFieldData();Region region = simulation.getRegionManager().getRegion("Region");MeshPart meshPart = region.getMeshPart();for (Cell cell : meshPart.getCells()) {double currentPressure = pressureData.getDouble(cell);double newPressure = currentPressure * 1.1; // 增加10%压力pressureData.setDouble(cell, newPressure);}// 更新场数据pressureField.setFieldData(pressureData);}
}

3. 高级应用示例

3.1 基于位置的场函数修改

import star.common.*;
import star.base.neo.*;
import star.meshing.*;public class PositionDependentUDF extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 获取必要场和网格数据ScalarField tempField = (ScalarField) simulation.getFieldManager().getField("Temperature");FieldData tempData = tempField.getFieldData();Region region = simulation.getRegionManager().getRegion("Region");MeshPart meshPart = region.getMeshPart();// 定义热源位置和半径double[] heatSource = {0.0, 0.0, 0.0};double radius = 0.1;// 修改温度场for (Cell cell : meshPart.getCells()) {DoubleVector center = cell.getCenter();double distance = Math.sqrt(Math.pow(center.get(0) - heatSource[0], 2) +Math.pow(center.get(1) - heatSource[1], 2) +Math.pow(center.get(2) - heatSource[2], 2));if (distance < radius) {tempData.setDouble(cell, 500.0); // 设置热源温度}}tempField.setFieldData(tempData);}
}

3.2 边界条件UDF示例

import star.common.*;
import star.base.neo.*;
import star.flow.*;public class InletVelocityProfile extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 获取入口边界Boundary boundary = simulation.getRegionManager().getRegion("Region").getBoundaryManager().getBoundary("Inlet");// 创建自定义速度剖面UserFieldFunction velProfile = simulation.getFieldFunctionManager().createFieldFunction();velProfile.setFunctionName("InletVelocityProfile");velProfile.setDefinition("5.0 * (1 - (y/0.05)^2)"); // 抛物线剖面// 应用到场VectorField velocity = (VectorField) simulation.getFieldManager().getField("Velocity");velocity.setFieldFunction(velProfile);// 更新边界条件boundary.getBoundaryValues().get(velocity).setMethod(FieldFunctionMethod.class);}
}

4. 调试和优化技巧

日志输出：使用simulation.println()输出调试信息

simulation.println("当前单元温度: " + tempValue);

性能优化：
- 尽量减少循环中的对象创建
- 预先获取所有需要的数据引用
- 对大型网格考虑并行处理

错误处理：

try {// 代码块
} catch (Exception e) {simulation.println("错误: " + e.getMessage());
}

5. 部署UDF

编写完成后：

编译UDF（右键点击UDF → 编译）
将UDF分配给适当的场函数或边界条件
运行模拟测试UDF效果

C/C++实现UDF

STAR-CCM+支持用户通过用户定义函数(UDF)来扩展软件功能，可以使用C/C++编写。以下是详细的实现方法和示例。

UDF基本实现步骤

创建UDF源文件：创建.c或.cpp文件
编译UDF：在STAR-CCM+中编译
关联UDF：将编译后的UDF关联到相应的模拟组件

引用场数据和网格数据的示例

示例1：简单的标量场处理

#include "star/StarMacros.h"
#include "star/Real.h"
#include "star/FieldData.h"
#include "star/Region.h"
#include "star/Mesh.h"
#include "star/IndexedMesh.h"// 定义UDF入口函数
void user_function()
{// 获取当前区域Region* region = get_CurrentRegion();// 获取网格IndexedMesh* mesh = get_IndexedMesh(region);// 获取速度场FieldData* velocityField = get_FieldDataByName(region, "Velocity");// 获取压力场FieldData* pressureField = get_FieldDataByName(region, "Pressure");// 检查字段是否存在if(!velocityField || !pressureField) {printf("Error: Required fields not found!\n");return;}// 获取单元数量int numCells = mesh->getNumberOfCells();// 遍历所有单元for(int i = 0; i < numCells; i++) {// 获取单元中心坐标real coord[3];mesh->getCellCenter(i, coord);// 获取速度值real vel[3];velocityField->getCellValue(i, vel);// 获取压力值real pressure;pressureField->getCellValue(i, &pressure);// 计算速度大小real velMag = sqrt(vel[0]*vel[0] + vel[1]*vel[1] + vel[2]*vel[2]);// 可以在这里进行自定义计算// 例如：修改压力值real newPressure = pressure * 1.1; // 增加10%pressureField->setCellValue(i, &newPressure);}
}

示例2：边界条件UDF

#include "star/StarMacros.h"
#include "star/Real.h"
#include "star/FieldData.h"
#include "star/Region.h"
#include "star/Boundary.h"
#include "star/Mesh.h"void boundary_udf()
{// 获取边界区域Boundary* boundary = get_CurrentBoundary();// 获取关联的网格和场数据Region* region = boundary->getRegion();FieldData* temperatureField = get_FieldDataByName(region, "Temperature");FieldData* velocityField = get_FieldDataByName(region, "Velocity");// 获取边界上的面数量int numFaces = boundary->getNumberOfFaces();// 遍历边界上的所有面for(int i = 0; i < numFaces; i++) {// 获取面中心坐标real coord[3];boundary->getFaceCenter(i, coord);// 根据位置设置边界条件if(coord[0] < 0.5) {// 区域x<0.5设置固定温度real temp = 300.0; // 300KtemperatureField->setBoundaryValue(boundary, i, &temp);// 设置速度为零（无滑移）real vel[3] = {0.0, 0.0, 0.0};velocityField->setBoundaryValue(boundary, i, vel);} else {// 其他区域设置热通量real heatFlux = 1000.0; // W/m2temperatureField->setBoundaryGradient(boundary, i, &heatFlux);}}
}

示例3：随时间变化的源项

#include "star/StarMacros.h"
#include "star/Real.h"
#include "star/FieldData.h"
#include "star/Region.h"
#include "star/Simulation.h"void time_dependent_source()
{// 获取当前模拟时间Simulation* sim = get_Simulation();real currentTime = sim->getCurrentTime();// 获取区域和场数据Region* region = get_CurrentRegion();FieldData* energySourceField = get_FieldDataByName(region, "EnergySource");// 正弦波时间变化real frequency = 1.0; // Hzreal amplitude = 1000.0; // W/m3// 计算当前时间下的源项幅值real sourceValue = amplitude * sin(2.0 * M_PI * frequency * currentTime);// 获取单元数量int numCells = region->getMesh()->getNumberOfCells();// 应用源项到所有单元for(int i = 0; i < numCells; i++) {energySourceField->setCellValue(i, &sourceValue);}
}