Development of an Air-Recirculated Ventilation System for a Piglet House, Part 1: Analysis of Representative Problems through Field Experiment and Aerodynamic Analysis Using CFD Simulation for Evaluating Applicability of System

Abstract

As the pig industry develops rapidly, various problems are appearing both inside and outside the pig houses. In particular, in the case of pig houses, it is difficult to solve the main problems even if automation and mechanization are applied with ICT technology. The main current issues are: (1) preventing infectious diseases amongst livestock, (2) reducing the emission of harmful gas and odors, (3) improving the growth environment inside the pig house, (4) reducing energy costs, (5) improving the farm management and operating system, and 6) improving the livestock product quality. Air recirculation technology can be applied as a technology that can solve these typical problems in the pig industry. An air-recirculated ventilation system can minimize the inflow of air from outdoors and recycle the internal thermal energy of the pig house. The air-recirculated ventilation system consists of (1) an air scrubber module, (2) external air-mixing module, (3) UV cleaning module, (4) solar heat module, and (5) air-distribution module. First, in this study, the field data were collected to analyze the main problems of the target piglet house for the application of the air-recirculated ventilation system. In addition, a computational fluid dynamics (CFD) model was developed and validated for seasonal aerodynamic analysis. The applicability of the air-recirculated ventilation system was evaluated based on the CFD computed results for various environmental conditions. As a result of evaluating the internal environment according to the ventilation rates and external-air-mixing ratio of the air-recirculated ventilation system, the required ventilation rate and external air-mixing ratio to maintain the proper temperature and gas concentration were determined.