Influences of parameter selection on the calculation speed and the accuracy of the results in the process of fluid topology optimization are studied for the airfoil topology optimization problem with low Reynolds number on the basis of the improved level set method. A new parameter m is introduced to describe the evolution times of the level set function in every iterative step and to control the accuracy and speed of evolution. An appropriate time step coefficient k is selected by numerical derivation
and the parameter selection rules that affect the convergence and speed of the numerical calculation are obtained. Results show that larger values of m and k will lead to unstable convergence and inaccurate convergence data
while smaller values of m and k will reduce the calculation speed. Functions of the parameters m and k and iterative steps are established
respectively
and the convergence speed increases by 85% and 80%
respectively on the premise of satisfying the accuracy of optimization. When selection ways of m and k are improved at the same time
the convergence speed will increase by 96%.
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references
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