Simulation Research Of Summer Internal Environment In A Smart Broiler Chamber Based On CFD

Smart breeding attaches great importance to the environmental conditions of the chickens’ living area.In order to overcome the problems of uneven air distribution,low ventilation efficiency,and untimely discharge of pollutants,the study was carried out on the self-designed miniature broiler house.In this paper,the Computational Fluid Dynamics(CFD)method is used to study and establish the summer ventilation field model and the summer ammonia diffusion model of the chicken house.The main conclusions were as follows:(1)The three-dimensional model of the chicken house was established by SolidWorks based on the field measurement and field experiment in the self-designed chicken house,and the instruments and methods for ventilation scheme design and internal environment detection of the chicken house were selected.The CFD model was established.The CFD equation and boundary conditions were established.CFD simulation technology can be used as an effective tool for the environment simulation of the chicken house.(2)In the study of the chicken house ventilation system during summer,Fluent was used as the solver for numerical calculation.Comparing the simulation results with the measured results,the Root Mean Square Error(RMSE)of the wind speed at each measuring point was 19.1%at most,and the maximum absolute error is 0.27m/s.Through numerical simulation,it is found that a good indoor circulation effect can be formed when the inner circulation is turned on,and the more uniform the whole wind field.The frequency conversion fan of the ventilation system was designed to control the temperature change in different periods.In the high-temperature area above 30℃,the vent speed is close to 2m/s.which is conducive to the chicken’s sense of cooling.The internal wind speed can be regulated at more than 0.8m/s.which conforms to the chicken’s ventilation standard in summer.For the air age of the chicken house,the bottom air can be renewed within 100s under a high-temperature environment.When the fifth working condition is opened at night,the air can be renewed once in every part of the house between 150s and 180s,which can meet the ventilation design standard of the chicken house.(3)According to the quality of ammonia in the existing ventilation mode,the problems of the current ventilation mode were analyzed.The simulation results show that in summer,Fan A=20Hz is challenging to meet the requirements of the indoor environment quality of chickens,and the ammonia concentration in the side of the internal circulation is high,and the multi-dimensional concentration is above 15ppm.Fan A=30Hz and Fan A=50Hz can both keep proper ventilation in the room,which is conducive to the discharge of ammonia.According to the streamline diagram of the simulation results,it is observed that after the ammonia gas is generated,the gas rises to the top in a circuitous way,then descends and discharges,and the flow path is long.Based on the fact that ammonia is lighter than air,this paper puts forward an improved scheme for the structure of the existing chicken house and uses CFD technology for simulation analysis.(4)The ammonia emission of the improved chicken house was analyzed by CFD simulation.The results show that the total ammonia concentration in the top opening can be significantly reduced,except that the ammonia concentration in the non-diffusion path is less than 3ppm,which indicates that the improved chicken house plays a significant role in promoting the ammonia emission.The top opening is conducive to the ammonia.