Analysis Of Concentration And Temperature Field In Large Mechanical Ventilation Broiler House

Large modern broiler house use high-density breeding, ammonia and other harmful substances are easily produced in broiler house. Environmental control plays a very important role in the poultry raising. Good house living environment is a prerequisite for the healthy growth of the chicken, and is an important guarantee for the chicken to improve product quality. The requirements of chicken breeding environment（for example: air velocity, high temperature and NH₃ concentration） are high. So it is necessary to do simulation study of sheds environment.The aim of this paper is to get the simulation analysis of flow velocity, temperature and NH₃ concentration, and so to obtain variation of airflow inside the broiler house. Study the rationality of airflow distribution of displacement ventilation with duct in the broiler house. Effect on environment in the broiler house was done with a given ventilation scheme, and optimized design was given for the mechanical ventilation broiler house.First, a physical model and mathematical model were established for the mechanical ventilation broiler house, and then Fluent software was used to simulate the airflow of the mechanical ventilation, the distribution of airflow velocity, temperature, ammonia concentration were calculated. The simulation analysis results show that air velocity distribution, the temperature distribution and the ammonia concentration were nonuniform when using ventilation ducts in displacement ventilation, meanwhile cyclone was produced in this kind of system, and these factors has a certain influence on the comfort of broilers. The conclusions of these simulations for further study of mechanical ventilation control provide data and theoretical basis.Secondly, on the basis of steady-state simulation, transient simulation was done with the mechanical ventilation for NH₃ premixed condition and the variety characteristics of the concentration of NH₃ within different time periods was got. Compared the concentration of NH₃ in the same position with different time, subperiod mechanical ventilation can dynamically adjust the flow conditions in the broiler house and to achieve energy saving.Finally, this paper also perform analysis and optimization design for the mechanical ventilation of the broiler house. Analyze the advantages and disadvantages of the influence of air distribution in broiler house under the different air volume and different amount air outlet opening of the duct, summary the design scheme of dilute ammonia concentration in the broiler house. We can obtain the optimization scheme of the ventilation design of the whole broiler house from the above analysis, the scheme we obtain can make broilers growth more comfortable, improve the quality of broilers products, achieve the goal of energy saving and provide theoretical and technical support for production operators at the same time.