一种新的计算非稳态流动的自适应无网格方法
发布时间：2018-11-15 19:02
【摘要】：基于带权点填充布点方法,结合指定流场参数梯度的分布,提出了一种新的无网格自适应方法计算非稳态问题。该方法的自适应探测器E由节点的权重和参数梯度组成。使用自适应探测器识别出加密或者粗化的区域,形成加密空腔和粗化空腔,然后重新填充布点。新节点的权重由自适应探测器E结合该处的梯度大小通过预测-校正迭代算法计算得到。另外,由于参数梯度在激波附近波动范围比较大,所以新节点的权重存在最大值和最小值。首先对预先设置压强梯度的流场区域进行自适应布点,并与传统自适应布点结果进行对比,点云分布图显示所提自适应方法重新生成的点云结构疏密分布更加合理。进一步,将此自适应方法应用于Riemann问题和激波碰撞圆柱问题,计算结果表明该方法可以在节点数目较低的情况下显著提高运动激波的分辨率。在激波碰撞圆柱问题中,比较了使用自适应算法和非自适应算法得到相当的结果所使用时间,前者是后者的20.6%,因此该自适应算法在计算效率方面也具有较大的优势。
[Abstract]:A new meshless adaptive method is proposed to calculate the unsteady state problem based on the weighted point-filled placement method and the distribution of the specified flow field parameter gradient. The adaptive detector E of this method consists of the weights and parameter gradients of the nodes. An adaptive detector is used to identify the encrypted or roughened areas, to form an encrypted cavity and a coarse cavity, and then to repopulate the points. The weight of the new node is calculated by using the predictor-correction iterative algorithm combined with the adaptive detector E and the gradient. In addition, due to the large fluctuation range of the parameter gradient near the shock wave, the weight of the new node has the maximum value and the minimum value. Firstly, the flow field with preset pressure gradient is arranged adaptively, and compared with the traditional adaptive distribution results, the point cloud distribution diagram shows that the proposed adaptive method is more reasonable to generate the point cloud structure density distribution. Furthermore, the adaptive method is applied to the Riemann problem and the shock wave collision problem. The results show that the method can improve the resolution of the moving shock wave significantly when the number of nodes is low. In the shock wave collision cylinder problem, the time of using adaptive algorithm and non-adaptive algorithm are compared. The former is 20.6 of the latter, so the adaptive algorithm also has a great advantage in computing efficiency.
【作者单位】： 南京理工大学能源与动力工程学院;
【分类号】：O35
，
本文编号：2334170
[Abstract]:A new meshless adaptive method is proposed to calculate the unsteady state problem based on the weighted point-filled placement method and the distribution of the specified flow field parameter gradient. The adaptive detector E of this method consists of the weights and parameter gradients of the nodes. An adaptive detector is used to identify the encrypted or roughened areas, to form an encrypted cavity and a coarse cavity, and then to repopulate the points. The weight of the new node is calculated by using the predictor-correction iterative algorithm combined with the adaptive detector E and the gradient. In addition, due to the large fluctuation range of the parameter gradient near the shock wave, the weight of the new node has the maximum value and the minimum value. Firstly, the flow field with preset pressure gradient is arranged adaptively, and compared with the traditional adaptive distribution results, the point cloud distribution diagram shows that the proposed adaptive method is more reasonable to generate the point cloud structure density distribution. Furthermore, the adaptive method is applied to the Riemann problem and the shock wave collision problem. The results show that the method can improve the resolution of the moving shock wave significantly when the number of nodes is low. In the shock wave collision cylinder problem, the time of using adaptive algorithm and non-adaptive algorithm are compared. The former is 20.6 of the latter, so the adaptive algorithm also has a great advantage in computing efficiency.
【作者单位】： 南京理工大学能源与动力工程学院;
【分类号】：O35
，
本文编号：2334170
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