基于CFD的叠层笼养肉鸭舍多孔介质模型简化及生长阶段阻力系数OA

To address the engineering requirements for ventilation optimization in tiered-cage meat duck houses at different growth stages,computational fluid dynamics(CFD)was employed to establish four simplified duck geometric models:One detailed model,one head-removed model,one torso model,and one ellipsoid model.Systematic analysis was conducted to examine the differences and trends in resistance coefficients along the length(X),width(Y),and height(Z)directions of the duck cage for duck models at different ages.Additionally,the dynamic variations in the resistance characteristics of the duck activity area were investigated.The results indicate that:1)The level of simplification of the duck model has a significant impact on the resistance coefficients.The inertial resistance error between the detailed model and the headless model was the smallest,with deviations of-15.7％,-13.1％,and 7.1％in the X,Y,and Z directions,respectively,while the errors for the other two models were larger,reaching a maximum of-44.4％.2)During the growth process of the ducks,as their body weight increased from 0.19 to 2.82 kg,the inertial and viscous resistance coefficients in the X,Y,and Z directions significantly increased,and the increase was the most pronounced in the Z direction.In conclusion,the resistance coefficients for ducks at different growth stages and the model simplification methods proposed in this study can provide key parameter support for CFD ventilation simulations in tiered-cage meat duck houses.