Analysis on frosting of heat exchanger and numerical simulation of heat transfer characteristics using BP neural network learning algorithm

• Published in: PloS one Vol. 16; no. 9; p. e0256836
• Main Authors: Yu, Bo, Luo, Yuye, Chu, Wenxiao
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 02.09.2021; Public Library of Science (PLoS)
• Subjects: Adaptive algorithms; Adaptive control; Air; Air conditioning; Air temperature; Algorithms; Analysis; Back propagation networks; Biology and Life Sciences; Computer and Information Sciences; Computer Simulation; Control theory; Earth Sciences; Economic development; Electrical Equipment and Supplies; Emissions control; Energy conservation; Energy consumption; Energy efficiency; Equipment and supplies; Evaluation; Evaporators; Freezing - adverse effects; Heat conductivity; Heat exchangers; Heat pumps; Heat transfer; Heating; Heating - instrumentation; High humidity; Hot Temperature; Humidity; Humidity - adverse effects; Laboratories; Low temperature; Machine Learning; Mathematical models; Models, Theoretical; Network control; Neural networks; Neural Networks, Computer; Numerical simulations; Physical Sciences; Regression analysis; Regression models; Research and Analysis Methods; Service life; Simulation; Sustainable development; Water - chemistry; Water shortages; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0256836

The study is aimed at the frosting problem of the air source heat pump in the low temperature and high humidity environment, which reduces the service life of the system. First, the frosting characteristics at the evaporator side of the air source heat pump system are analyzed. Then, a new defrost technology is proposed, and dimensional theory and neural network are combined to predict the transfer performance of the new system. Finally, an adaptive network control algorithm is proposed to predict the frosting amount. This algorithm optimizes the traditional neural network algorithm control process, and it is more flexible, objective, and reliable in the selection of the hidden layer, the acquisition of the optimal function, and the selection of the corresponding learning rate. Through model performance, regression analysis, and heat transfer characteristics simulation, the effectiveness of this method is further confirmed. It is found that, the new air source heat pump defrost system can provide auxiliary heat, effectively regulating the temperature and humidity. The mean square error is 0.019827, and the heat pump can operate efficiently under frosting conditions. The defrost system is easy to operate, and facilitates manufactures designing for different regions under different conditions. This research provides reference for energy conservation, emission reduction, and sustainable economic development.