The differential quadrature method and differential quadrature element method for the acoustic radiation

Based on the Helmholtz equation in unbounded domain, the differential quadrature method and differential quadrature element method were applied to the calculation of two-dimension and three-dimension acoustic radiation. The different orders of artificial boundary conditions were applied to the nodes in the outer layer, and the uniform and nonuniform node distributions were used in the calculation domain. The influence of different node distributions and approximate boundary condition orders on the numerical results was presented. And the precision of these two numerical methods was compared. The results show that for the differential quadrature method and differential quadrature element method, the former has the higher precision while the latter has the less calculation time and quality benefit-cost radio in the low-frequency. The approximate boundary conditions are mainly taking effect in the low-frequency, while the nodes distributions are mainly taking effect in the high-frequency. The nonuniform node distribution has the higher precision in the different frequencies.