The Application of Shape Gradient for the Incompressible Fluid in Shape Optimization

This paper is concerned with the numerical simulation for shape optimization of the Stokes flow around a solid body. The shape gradient for the shape optimization problem in a viscous incompressible flow is evaluated by the velocity method. The flow is governed by the steady-state Stokes equations coupled with a thermal model. The structure of continuous shape gradient of the cost functional is derived by employing the differentiability of a minimax formulation involving a Lagrange functional with the function space parametrization technique. A gradient-type algorithm is applied to the shape optimization problem. Numerical examples show that our theory is useful for practical purpose, and the proposed algorithm is feasible and effective

Influence of visual factors on noise annoyance evaluation caused by road traffic noise in indoor environment

ABSTRACT Through laboratory experiments the variation of noise annoyance caused by road traffic noise with L Aeq.20sec of 35, 45, 55 and 65dB under different visual conditions in study and living rooms was explored. The experimental result shows that in the indoor environment the influence of brightness perception on noise annoyance caused by road traffic noise was more obvious, and the effect of color perception on noise annoyance evaluation was not significant though color and brightness had an interaction effect on noise annoyance evaluation. Therefore, both improving the lighting conditions and creating a reasonable combination of color and brightness condition was helpful for the noise control in the indoor environment