Abstract：Mesh quality influences numerical accuracy and computational efficiency directly in CFD. In order to improve the quality of mesh on solid boundaries in a centrifugal pump greatly, an optimization-based smoothing algorithm is proposed. In this algorithm, a new mesh quality metric is employed, and an error function is derived by transforming the metric. The total error function of the mesh is the sum of the error in every element, and adopted as the objective function of the optimization. Furthermore, in the objective function, the qualities of the mesh on and off the boundaries are involved, a weight coefficient is also included to control the quality of the mesh on the boundaries. The Broyden Fletcher Goldfarb Shanno algorithm is applied to transform the global minimization to a series of local minimization to enhance the computational efficiency. A practical example shows that the proposed algorithm can improve the mesh quality considerably; moreover not only the quality of the mesh on the boundaries but also the overall quality of all the mesh can be upgraded with the increasing weight coefficient as well.
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