解非均匀区域油藏模拟问题的一种有效并行计算方法

Valid Parallel Algorithm for Nonuniform Domain Simulation of Reservoir

运用区域分解方法求解油藏模拟问题 ,结合灵活的区域划分和负载平衡策略 ,可以提高解题速度 .但一般区域分解方法在应用中存在算法收敛慢 ,计算量增加 ,虽有一定加速比 ,但提高不大 .特别是对非均匀区域的应用问题 ,子区域收敛速度不同引起的负载不均衡进一步导致性能下降 .本文基于分布式并行系统 ,运用整体预处理改进区域分解方法 ,降低了非均匀油藏模拟问题的计算复杂性 ,提高了模拟计算的速度 ,并根据全局和本地负载状态调整区域划分 ,结合有效的负载平衡策略 ,达到对一类黑油模型油藏模拟问题高效的并行求解 .实验结果表明 ,模拟速度有较大提高 。

The domain decomposition method, when combined with flexible decomposition and load-balancing strategies, can improve the parallel performance of iterative computations and save the costs in large-scale numerical reservoir simulations. However, the ordinary domain decomposition method was found to have problems of increased computational load and slowed convergence, especially in working with non-uniform domain numerical simulations. Here, we report the results of an efficient parallel approach that we have recently designed and implemented. This approach used preconditioned domain decomposition method and load-balancing strategy based on the distributed parallel environment to reduce the computational complexity of non-uniform numerical reservoir simulations and enhance the computational speed. Our computational results showed that the simulation speed was improved largely with a high speedup.