Математическая модель очистки кожного покрова коров для повышения интенсивности теплового обмена при тепловых стрессах

Abstract

Automatic brushing devices that improve the sanitary-hygienic condition of animal skin and create comfortable conditions are becoming widespread in modern dairy farms. To verify the developed mathematical model of cow skin cleaning, the authors carried out experimental studies on ten animals on a dairy farm. On the lateral surface of each animal three zones with the area of 10×10 cm2 were selected: the first area was not cleaned; the second area was cleaned “dry” with a brush; the third area was subjected to “wet” cleaning with a brush and detergent (soap solution). The temperature of the skin areas was determined for 15 minutes by the non-contact method using a pyrometer. The study results confirmed the effect of skin cleaning on the intensity of animal heat exchange due to increased convection and evaporation under heat stress. It was found that wet cleaning is the most effective method, when the skin temperature decreases by 4.1°C due to the increase in heat transfer by evaporation, while after dry cleaning it is 0.7°C. The developed mathematical model of cow skin cleaning establishes the relationship between the parameters of the brush bristle impact on the contaminated skin surface, the brush device and cleaning modes. The received dependences determine technical requirements and rational design and mode parameters of the brushing device to develop an automatic station of cow skin cleaning on farms.