Simulation of temperatures in a broiler chicken house in Kenya

Abstract

The research reported in this thesis was conducted at the University of Nairobi with a broad objective of developing appropriate criteria for environmental design and control in a poultry house in Kenya. The specific objectives of the study were: to identify the pertinent physical parameters, which affect the temperatures in a broiler chicken house; use the identified parameters to develop a mathematical model for simulation of temperatures in a poultry house in Kenya; use computer simulation to solve the model developed and use physical model of the poultry production structure, to test and verify the model developed. Mathematical modelling and simulation were done based on the climatic and constructional parameters that affect the temperature response of the poultry house and the established theoretical work. The modelling of the dynamics of energy balance of the building microclimate was developed and the temperatures of the building were solved analytically. The equations developed had the input parameters: outside air temperature; total solar radiation; mass rate of airflow; properties and dimensions of the constructional materials; number of birds and their average weight as well as the air properties to predict hourly internal air temperature of a poultry house and sol air temperature. The mathematical model of the internal environment, which was developed, was solved using a computer program written in Delphi. The program solves analytically the temperatures of the building with the results presented, which compare the model with experimental measurements made in a naturally ventilated poultry house. A numerical analysis technique, finite element method, was used to approximate the temperatures at various locations of the poultry house. Experiments were performed using a physical model to test and verify the model at the University of Nairobi, Department of Animal Production at Kabete Campus, during the month of March 2002. Results demonstrated no significant difference between the internal air temperatures obtained by simulations and observed measurements. Statistical analysis indicated that the model adequately simulated the internal environment of the building. U