Numerical study on hybrid heating technologies for a greenhouse

In this paper, we used TRNSYS software to firstly investigate the economics and environmental friendliness of three heating systems, namely, electric boiler (EB) heating system, solar assisted electric boiler (SAEB) heating system and solar assisted air source heat pump (SAASHP) heating system, in greenhouses, and the results showed that the SAASHP system has the lowest operating costs and a payback period of 8.7 years. Subsequently, the greenhouse with SAASHP heating system and built-in film was simulated using ANSYS Fluent software. The purpose of the film is to reduce the heating space and energy consumption, and the changes in the energy consumption of the system and greenhouse heating before and after the film was placed were compared using TRNSYS software, and the velocity field and temperature field before and after the film was placed were simulated and compared with the film using ANSYS Fluent software. Temperature field before and after film placement were simulated and compared using ANSYS Fluent software. The simulation results show that after the film is used in the SAASHP system, the greenhouse heating heat load is reduced by 42.8%, the heating operation energy consumption is reduced by 19.9%, the greenhouse temperature distribution is more uniform, and the film return on investment cycle is 1 year, so it has a higher value of use. The above results show that greenhouse built-in films are beneficial for greenhouse heating in cold regions. This study provides new ideas for clean and efficient greenhouse heating in cold regions and provides data support for related research.