网络分布式仿真平台的搭建

当今的CAE分析工作一般是按学科分类而单独进行的，主要的学科有碰撞安全、车辆动力学、可靠、耐久、NVH、空气动力学等，每个学科与CAD数据的交互都是内部循环。在进度配合上，每个学科之间的工作进展不同步，在工作内容上难以体现学科交叉效应（见图9.9）。

图9.9　传统的多学科CAE并行工作方法［13］

传统分析方法中各个学科同时拿到上一轮冻结的系统CAD数据，根据自己的学科规则进行子系统拆分和建模，用自己学科的求解器进行求解，然后根据专业知识对结构设计方案进行优化，提出自己的改进设计方案，再提交给结构设计师。如果有n个学科，设计师就会收到n个这样的设计方案。假设设计师先将学科1的设计方案体现到结构设计，当体现学科2的设计方案时，学科1的性能就有可能受到影响，依次类推。

网络分布式仿真分析平台的工作方法见图9.10。各个学科拿到第一轮设计的CAD数据后，按照统一规则将整车分解成子系统，形成多学科组合文件，送入Mega-Solver进行求解，结果交由产品项目的性能主管对各个学科的性能进行均衡和协调，然后将统一的结构设计更改方案交由产品设计师。需要指出的是，性能的均衡必须由人工进行判断，因为这代表了一个具体产品的价值取向，是不能由机器代替执行的。

图9.10　网络分布式仿真平台［13］

搭建网络分布式仿真平台时的一个学科组合案例见图9.11。

图9.11　网络分布仿真平台的学科组合案例

在9.10中，多体与有限元的耦合网络通信见图9.12。利用MATLAB语言为主控机编写控制代码，通过OPC服务器技术可以对客户机实现任务分配管理及传递客户机的计算结果。为客户机编写的计算控制代码可以接受或等待主机分配计算任务，并接收主机传递的计算结果数据，根据计算需要可以连接多台客户机。OPC数据服务器结构见图9.13。

图9.12　基于OPC的多体与有限元的耦合网络通信

图9.13　OPC数据服务器

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