层叠式笼养肉鸭舍秋季最小通风的环境参数测试及分析

Mensuration and analysis of environmental parameters in cascading cage-rearing meat duck house with minimum ventilation in the autumn

本研究旨在探讨最小通风模式对层叠笼养肉鸭舍内环境参数的影响。选择秋季肉鸭育肥后期(32~35日龄)进行试验,通过检测鸭舍内温度、湿度、风速、NH3质量浓度、CO2质量浓度,构建鸭舍CFD模型,模拟并分析温度场与气流场分布特征。结果表明:连续测试4 d,舍外温度6.31~26.12℃,舍内气温15.98~24.85℃;舍外相对湿度13.74%~91.49%,舍内相对湿度28.94%~79.68%;舍内风速波动范围0.30~0.81 m/s,CO2与NH3质量浓度变化范围分别为1462~2798 mg/m3、0.05~0.87 mg/m3。模拟试验鸭舍温度场与气流场,模拟仿真值与实测值间相对误差为0.8%~1.3%,说明所建CFD模型数值模拟与试验数据间高度吻合。每层鸭笼水平剖面温度场与气流场分布模拟结果分别揭示了各层面纵向中部温度均高于两端区域,以及各层中部至风机处气流流速均大于其他区域;此外,南北两侧对称分布通风小窗进入气流形成对冲并汇聚,致使气流分布不均。该研究可为层叠笼养鸭舍结构优化设计与环境调控提供参考。

The study aimed to detect the effects of minimum ventilation mode on the environmental parameters in the cascading cage-rearing meat duck house.During the latter finishing period of meat duck(32-35 d)in the autumn,temperature,humidity,wind speed,CO2 mass concentration and NH3 concentration were measured,and CFD model of duck house was conducted to simulate and analyze the distribution pattern of temperature and airflow.The results showed that the outside air temperature was 6.31-26.12℃,and the inside air temperature varied from 15.98℃to 24.85℃during four consecutive days of testing.The relative humidity outside the house was 13.74%-91.49%,and the inside relative humidity was 28.94%-79.68%.The air speed in the house was 0.30-0.81 m/s,and the mass concentrations of CO2 and NH3 were 1462-2798 mg/m3 and 0.05-0.87 mg/m3,respectively.The relative error between simulated and measured results in temperature and wind speed was 0.8%-1.3%,which indicated the high agreement between the digital simulation of the constructed model and the experimental results.Simulated results along horizontal profile of each tier cage showed that inside air temperature at central region of each layer was higher than that in the forepart and back from longitudinal angle,while airflow velocity from the middle of each layer to the fan was higher than other areas.Furthermore,airflow field was uneven due to incoming airstream which from bilateral symmetry window run into each other and gathered.And this study can provide references for the optimization design and environmental regulation of cascading cage-rearing duck house.