A two-node mechanistic thermophysiological model for pigs reared in hot climates – Part 2: Model performance assessments. (December 2021)

• Record Type: Journal Article
• Authors: Huang, Tao; Rong, Li; Zhang, Guoqiang; Brandt, Pia; Bjerg, Bjarne; Pedersen, Poul; Granath, Simon W.L.
• Is Part Of: Biosystems engineering. Volume 212(2021)
• Page Start: 318
• Page End: 335
• Publication Date: 2021-12
• Subjects: Convective heat transfer coefficient -- Mechanistic model -- Pig thermoregulation -- Pulmonary ventilation rate -- Vasodilatation; Bioengineering -- Periodicals; Agricultural engineering -- Periodicals; Biological systems -- Periodicals; Génie rural -- Périodiques; Systèmes biologiques -- Périodiques; 631
• DOI: 10.1016/j.biosystemseng.2021.08.021
• Languages: English
• ISSNs: 1537-5110

Abstract

Abstract : The performance of the mechanistic two-node thermophysiological model was assessed using the experimental data with respect to gestating sows and fattening pigs. The relation between the convective heat transfer coefficient and local airspeed was derived from CFD simulation. The improvement brought by the newly proposed active module over the selected available models was analysed and discussed. Generally, the proposed two-node model with novel active modules for pulmonary ventilation rate (related to panting) and vasodilatation could predict rectal and skin temperatures for fattening pigs and gestating sows with an error of 0.88% and 3.96%, and 0.42% and 1.27% respectively. Employing existing relationships for pulmonary ventilation rate and vasodilatation resulted overestimations on the skin and rectal temperature. Additionally, the convective heat transfer coefficient should be developed based on the field conditions when the flow pattern is not similar to that under which the existing models were developed. The mean radiant temperature should be input with a decent level of accuracy when a high level of accuracy of prediction was necessary. The proposed model is reliable and robust when predicting the pig thermal status under various climate conditions and it is expected to be applied when operating the technical approaches to mitigate the heat stress. Highlights: Experimental measurements conducted under various test conditions. Thermophysiological model for pigs validated using experimental data. Influence of the active modules on the model performance investigated. Convective heat transfer coefficient determined by CFD simulations.