Mathematical formulation of the animal thermal status has been developed, with the account of two convenience conditions and heat balance, for the floor-mounted heating panel for prenursery pigs. The borders of the heat flux variation range for the floor-mounted heating panel have been determined corresponding to the animal-friendly conditions for prenursery pigs of various age groups. The block diagram of the energy-saving floor-mounted heating panel, comprising the thermoelectric assembly operating in the heat pump mode, has been designed. The method has been described and the corresponding calculations have been made for the basic thermal parameters of the floor-mounted local heating installation, for prenursery pigs, with the application of a thermoelectric heat pump. The experimental installation sample of 116 W thermal capacity (for the heat transfer coefficient from 0.9 W·m−2·K−1 to 1.0 W·m−2·K−1 and floor temperature in the range of 5 °C to 6 °C) has been developed and manufactured for local heating for prenursery pigs managed in gestation crates. Laboratory tests of the experimental sample of the floor-mounted heating panel have demonstrated high energy efficiency of the heating installation under development. The energy-saving effect (approx. 15% compared to the series-produced equipment designed for local heating of young stock) of the developed installation was achieved owing to the partial heat recuperation of the exhaust ventilating air.
Recommendations on the selection of air curtains and the calculation of their parameters for livestock premises in cattle management farms are made. The air curtain functioning principle is analyzed from the air jet theory point of view. The block diagram and modular design of air curtains with a variable air jet direction vector and with controlled slit width are designed. Laboratory tests of the newly designed air curtain structure are performed in accordance with the microclimate requirements for the cattle management farm premises. Based on the experimental results, the major air curtain parameters are calculated for the range from 10° to 60° of angle α between the direction of the air jet outward from the air curtain slit and aperture plane, and for the air curtain slit width b0 in the range from 0.05 m to 0.15 m with the account of the wind speed Vw variations. Calculated values for amounts of energy that have to be consumed to ensure the required air jet velocity, in the output from the air curtain, and those for the quantity of thermal energy required to heat the air supplied to the air curtain, depending on the angle α and on the slit width b0, can be helpful for selecting the power capacity of both the air curtain fan and electric heater. A block diagram of the air curtain control for cattle management farm premises is designed, enabling automatic control of the airflow rate, the angle of the air jet output from the air curtain slit, and the temperature of the heated air supplied to the air curtain, considering particular climate conditions. According to the preliminary estimate, applications of the newly designed air curtain will make it possible to reduce the energy consumed to maintain the required microclimate conditions in cattle management premises by 10% to 15% in the cold period.
This article presents the results of developing and testing the air-cooling system of a combined climate control unit used in pig farming. The authors have found a water-evaporative system to be the most efficient for cooling the air supply. Cooling systems of this type consume 0.003 kW/kW of electric power to produce 1 kW of cold. Based on the developed mathematical model for water-evaporative cooling in the combined climate control unit, the authors have determined that an air supply with a temperature of 31.2 °C and a relative humidity of 30.4% can be cooled by 8.3 °C when saturated with moisture to a relative humidity of 90.0% (by 11.7 °C at 100%). Experimental studies of the cooling system confirmed the theoretically obtained data.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.