海洋流线积分自适应步长计算模型研究  

Research on adaptive-step calculation model of marine fluid flow numerical integration

作　　者：李婷[1] 季民[1] 靳奉祥[2] 廖忠云 孙勇[1] 

机构地区：[1]山东科技大学测绘科学与工程学院,山东青岛266590 [2]山东建筑大学,山东济南250101

出　　处：《海洋学报》2018年第3期95-101,共7页

基　　金：国家自然科学基金(41471330);国家青年科学基金项目(41401439);高等学校博士学科点专项科研基金项目(20113718110001)

摘　　要：针对步长固定的传统流线数值积分中造成的计算不精确或无谓计算过多的问题,文献[15]提出了一种自适应步长的海洋流线构造算法,该算法中的自适应步长计算模型可综合考虑局部网格的流速和流向,具有双自由度调整的优点,但也存在着邻近网格流向改变过大造成的追踪不持续、网格内流速过缓造成的迭代死循环等问题,为此本文提出了一种新的自适应步长计算优化模型,优化后的模型在保持原模型优点的基础上,通过限定积分步长的下限取值范围,解决了流线追踪不连续及计算迭代死循环问题,同时通过调整参数μ及δ在模型中的控制范围,使积分步长的适用度更加宽泛,从而提高了算法的计算效率、减少了数据存储量,并避免了流线混叠及锯齿现象,通过大量试验及三维可视效果的对比分析,验证了算法的可行性和有效性。For the issues that existed in the old streamline numerical integration procedure which used the fixed integrating-step,such as inaccurate calculation results and unnecessary calculations,literature 15 presented the adaptive-step based marine fluid flow streamline constructing algorithm（AMFCA）.The adaptive-step integration model in AMFCA could use the local grid＇s flow direction and velocity at same time,and had the advantage of adjusting the integrating-step in two degrees of freedom.But the model also had several issues,such as the streamline tracking process interruption when the adjacent grids＇ flow direction changes rapidly,the calculation endless loop when the flow velocity is close to zero,and so on.In order to solve these problems,the paper gave a new adaptivestep integration optimization model.This new model kept all the advantages of the old model,and by limiting the integral step＇s lowest value,it resolved the front issues.In addition to this,through adjustedμandδ＇s control ranges,the new model also made the applicability of integration step more widely,improved the computing efficiency,reduced the number of sampling data,and avoided the overlap and saw teeth of streamlines.Through many experiments and 3 Dsimulating,it verified the practicability and feasibility of the new model.

关 键 词：海洋流场 流线追踪 数值积分 自适应步长 流场引导算法 

分 类 号：P731.21[天文地球—海洋科学]