在Star-CCM+中實現UDF并引用場數據和網格數據

Star-CCM+中的用戶自定義函數(UDF)允許用戶通過Java或C/C++編程擴展軟件功能。下面我將詳細介紹如何實現UDF并引用模擬數據。

1. UDF基礎實現方法

1.1 創建UDF的步驟

在Star-CCM+中，右鍵點擊"工具" → “用戶函數” → “新建”
選擇Java或C/C++作為編程語言
為UDF命名并選擇適當的模板
編寫代碼并編譯
將UDF分配給適當的場函數或邊界條件

1.2 Java UDF基本結構示例

import star.common.*;
import star.base.neo.*;
import star.meshing.*;public class MyUDF extends StarMacro {@Overridepublic void execute() {// 獲取當前模擬會話Simulation simulation = getActiveSimulation();// 獲取網格和場數據MeshPart meshPart = simulation.get(SimulationPartManager.class).getMeshPart();ScalarField temperatureField = simulation.getFieldManager().getField("Temperature");// 在這里處理數據...}
}

2. 引用場數據和網格數據的示例

2.1 訪問標量場數據示例

import star.common.*;
import star.base.neo.*;
import star.flow.*;public class TemperatureUDF extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 獲取溫度場ScalarField temperature = (ScalarField) simulation.getFieldManager().getField("Temperature");// 獲取當前迭代的場數據FieldData fieldData = temperature.getFieldData();// 遍歷所有單元獲取溫度值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);// 處理溫度數據...}}}
}

2.2 訪問矢量場和網格幾何數據示例

import star.common.*;
import star.base.neo.*;
import star.meshing.*;
import star.flow.*;public class VelocityUDF extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 獲取速度場VectorField velocityField = (VectorField) simulation.getFieldManager().getField("Velocity");FieldData velocityData = velocityField.getFieldData();// 獲取網格幾何數據Region region = simulation.getRegionManager().getRegion("Region");MeshPart meshPart = region.getMeshPart();// 遍歷單元計算速度大小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());// 獲取單元中心坐標DoubleVector center = cell.getCenter();double x = center.get(0);double y = center.get(1);double z = center.get(2);// 處理數據...}}
}

2.3 修改場數據示例

import star.common.*;
import star.base.neo.*;
import star.flow.*;public class ModifyFieldUDF extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 獲取并修改壓力場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%壓力pressureData.setDouble(cell, newPressure);}// 更新場數據pressureField.setFieldData(pressureData);}
}

3. 高級應用示例

3.1 基于位置的場函數修改

import star.common.*;
import star.base.neo.*;
import star.meshing.*;public class PositionDependentUDF extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 獲取必要場和網格數據ScalarField tempField = (ScalarField) simulation.getFieldManager().getField("Temperature");FieldData tempData = tempField.getFieldData();Region region = simulation.getRegionManager().getRegion("Region");MeshPart meshPart = region.getMeshPart();// 定義熱源位置和半徑double[] heatSource = {0.0, 0.0, 0.0};double radius = 0.1;// 修改溫度場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); // 設置熱源溫度}}tempField.setFieldData(tempData);}
}

3.2 邊界條件UDF示例

import star.common.*;
import star.base.neo.*;
import star.flow.*;public class InletVelocityProfile extends StarMacro {public void execute() {Simulation simulation = getActiveSimulation();// 獲取入口邊界Boundary boundary = simulation.getRegionManager().getRegion("Region").getBoundaryManager().getBoundary("Inlet");// 創建自定義速度剖面UserFieldFunction velProfile = simulation.getFieldFunctionManager().createFieldFunction();velProfile.setFunctionName("InletVelocityProfile");velProfile.setDefinition("5.0 * (1 - (y/0.05)^2)"); // 拋物線剖面// 應用到場VectorField velocity = (VectorField) simulation.getFieldManager().getField("Velocity");velocity.setFieldFunction(velProfile);// 更新邊界條件boundary.getBoundaryValues().get(velocity).setMethod(FieldFunctionMethod.class);}
}

4. 調試和優化技巧

日志輸出：使用simulation.println()輸出調試信息

simulation.println("當前單元溫度: " + tempValue);

性能優化：
- 盡量減少循環中的對象創建
- 預先獲取所有需要的數據引用
- 對大型網格考慮并行處理

錯誤處理：

try {// 代碼塊
} catch (Exception e) {simulation.println("錯誤: " + e.getMessage());
}

5. 部署UDF

編寫完成后：

編譯UDF（右鍵點擊UDF → 編譯）
將UDF分配給適當的場函數或邊界條件
運行模擬測試UDF效果

C/C++實現UDF

STAR-CCM+支持用戶通過用戶定義函數(UDF)來擴展軟件功能，可以使用C/C++編寫。以下是詳細的實現方法和示例。

UDF基本實現步驟

創建UDF源文件：創建.c或.cpp文件
編譯UDF：在STAR-CCM+中編譯
關聯UDF：將編譯后的UDF關聯到相應的模擬組件

引用場數據和網格數據的示例

示例1：簡單的標量場處理

#include "star/StarMacros.h"
#include "star/Real.h"
#include "star/FieldData.h"
#include "star/Region.h"
#include "star/Mesh.h"
#include "star/IndexedMesh.h"// 定義UDF入口函數
void user_function()
{// 獲取當前區域Region* region = get_CurrentRegion();// 獲取網格IndexedMesh* mesh = get_IndexedMesh(region);// 獲取速度場FieldData* velocityField = get_FieldDataByName(region, "Velocity");// 獲取壓力場FieldData* pressureField = get_FieldDataByName(region, "Pressure");// 檢查字段是否存在if(!velocityField || !pressureField) {printf("Error: Required fields not found!\n");return;}// 獲取單元數量int numCells = mesh->getNumberOfCells();// 遍歷所有單元for(int i = 0; i < numCells; i++) {// 獲取單元中心坐標real coord[3];mesh->getCellCenter(i, coord);// 獲取速度值real vel[3];velocityField->getCellValue(i, vel);// 獲取壓力值real pressure;pressureField->getCellValue(i, &pressure);// 計算速度大小real velMag = sqrt(vel[0]*vel[0] + vel[1]*vel[1] + vel[2]*vel[2]);// 可以在這里進行自定義計算// 例如：修改壓力值real newPressure = pressure * 1.1; // 增加10%pressureField->setCellValue(i, &newPressure);}
}

示例2：邊界條件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()
{// 獲取邊界區域Boundary* boundary = get_CurrentBoundary();// 獲取關聯的網格和場數據Region* region = boundary->getRegion();FieldData* temperatureField = get_FieldDataByName(region, "Temperature");FieldData* velocityField = get_FieldDataByName(region, "Velocity");// 獲取邊界上的面數量int numFaces = boundary->getNumberOfFaces();// 遍歷邊界上的所有面for(int i = 0; i < numFaces; i++) {// 獲取面中心坐標real coord[3];boundary->getFaceCenter(i, coord);// 根據位置設置邊界條件if(coord[0] < 0.5) {// 區域x<0.5設置固定溫度real temp = 300.0; // 300KtemperatureField->setBoundaryValue(boundary, i, &temp);// 設置速度為零（無滑移）real vel[3] = {0.0, 0.0, 0.0};velocityField->setBoundaryValue(boundary, i, vel);} else {// 其他區域設置熱通量real heatFlux = 1000.0; // W/m2temperatureField->setBoundaryGradient(boundary, i, &heatFlux);}}
}

示例3：隨時間變化的源項

#include "star/StarMacros.h"
#include "star/Real.h"
#include "star/FieldData.h"
#include "star/Region.h"
#include "star/Simulation.h"void time_dependent_source()
{// 獲取當前模擬時間Simulation* sim = get_Simulation();real currentTime = sim->getCurrentTime();// 獲取區域和場數據Region* region = get_CurrentRegion();FieldData* energySourceField = get_FieldDataByName(region, "EnergySource");// 正弦波時間變化real frequency = 1.0; // Hzreal amplitude = 1000.0; // W/m3// 計算當前時間下的源項幅值real sourceValue = amplitude * sin(2.0 * M_PI * frequency * currentTime);// 獲取單元數量int numCells = region->getMesh()->getNumberOfCells();// 應用源項到所有單元for(int i = 0; i < numCells; i++) {energySourceField->setCellValue(i, &sourceValue);}
}