Abstract: Abstract： In order to accurately simulate the wave propagation of waterway and basin area in the estuary of Sheyang River, first, based on the application of unstructured triangular mesh of the third generation wave model SWAN and using the unstructured grid nesting technology, a large area and shallow engineering nested sea wave mathematical model was established. Then, the large and small computational domain wave numerical models were veryfied and the calculated values and measured values agreed well. Finally, the various cases of harbor basin and channel wave parameter were calculated, providing a scientific basis for the design department. The research results show that by applying the nested grid technology, on the one hand, the number of grid computing field was greatly reduced and the compution speed was increased. On the other hand, more intensive computing grid which can adapt to the complex topography and winding coastline of the border can be constructed, thus, raising the accuracy of the calculation results.

Key words: unstructure, triangle mesh, nest, wave, numerical model