猪舍废气净化系统填料结构多目标拓扑优化设计与试验

Structural Optimization Design of Packing Material for Waste Gas Purification System of Pig House

摘要:

针对猪舍废气净化系统的填料结构，提出同时考虑结构机械性能与净化空间需求进行填料结构设计。将填料结构视为一种周期性结构，基于逆向均匀化方法和参数化水平集方法相结合的多目标拓扑优化方法，对周期性结构的单胞拓扑结构进行优化。以填料结构的最大等效体积模量和最大等效渗透率为优化目标，以等效孔隙率为约束条件，通过Hashin-Shtrikman属性边界得到等效体积模量及等效渗透率的极值，运用帕累托优化法求得满足多目标条件的帕累托最优解。根据帕累托最优解设计了不同孔隙率的填料结构构型，并通过试验验证填料结构设计方法的可行性与正确性。试验表明，填料结构前后端压力差与填料结构孔隙率成反比，与前端风速成正比；当填料结构孔隙率分别为80%、85%和90%时，稳定后平均除氨效率分别为66%、62%和58%。本研究可为猪场废气净化系统填料结构设计提供参考，可根据不同猪舍对风阻与净化效率的实际要求选择填料结构。

Abstract:

The structure of packing material was designed for waste gas purification system of pig house, and structural mechanical properties and purification space requirements were both considered in the designing process. The packing material was regarded as a kind of periodic structure, and the topology of the cell structure was optimized based on a multi-objective optimization method that combined the reverse homogenization method and the parametric level set method. In the optimization design, the maximum effective bulk modulus and the maximum effective permeability of the packing material were taken as the optimization objectives, and the effective porosity was taken as the constraint. The maximum values of effective bulk modulus and effective permeability coefficient were obtained by Hashin-Shtrikman property boundary. Pareto optimization method was used to achieve the Pareto optimal solution satisfying the multi-objective conditions. Three numerical examples achieved structural designs of the packing material under different porosities, and the feasibility and correctness of the proposed design method was verified by experiments. The experimental data showed that the pressure difference between front and rear of the packing material was inversely proportional to the porosity of the packing structure and directly proportional to the inlet wind speed. When the porosities of packing material were 80%, 85% and 90%, the average ammonia removal efficiencies were 66%, 62% and 58%, respectively. The research result can provide a reference for the design of the packing structure for waste gas purification system, and the proper packing material can be selected according to the actual requirement of wind resistance and purification efficiency in different pig houses.