Research On Air Conditioner Combining Convection And Radiation After Heat Exchange Between Air Film And Solid Metal Plate

Comfortable indoor thermal environment is one of the important ways to improve our work efficiency,quality of life,and learning efficiency.Convection air conditioners and radiant air conditioners are commonly used at this stage to improve the indoor thermal environment.They are powerful tools used by people to resist the indoor thermal environment caused by seasonal climate changes.However,there are also some shortcomings,for example: the large air volume and large temperature difference of convection air conditioners are easy to bring indoor people a sense of blowing of hot and cold.The radiation air conditioning system is complicated and it is not easy to cooperate.In order to solve the problems existing in the above air-conditioning apparatus,and combine the two unique advantages.In this article,the cold(hot)air film formed on the solid-wall radiant panel induced by Coanda surface is used to reduce(rise)the temperature of the solid-wall radiant panel,so as to increase its temperature difference with the indoor heat(cold)source to form radiant heat exchange.On this basis,combined with the small temperature difference and small flow velocity air circulation formed by the air film desorption from the solid wall radiation plate,a comfortable indoor environment that meets the requirements is created through a set of air conditioning systems.Explored the airflow characteristics and the radiation plate temperature characteristics of the air conditioner.And in the case of the same cold(hot)quantity delivered into the room,compared with the effect of the traditional convection air conditioner on the indoor environment.The specific research content is as follows:(1)Considering the fluid-solid coupling heat transfer between the attached cold(hot)air film and the solid wall radiation plate,the radiation heat exchange between the solid wall radiation plate and the indoor heat(cold)source,and the convection heat exchange between the air circulation and the indoor heat(cold)source,the relevant mathematical model and numerical simulation method are constructed in the numerical calculation process.(2)Based on the patent "Radiation Convection Air Conditioner Utilizing Air Film and Solid Wall Heat Exchange",a three-dimensional model is established to simulate the air flow characteristics of the air conditioner after heat exchanger treatment and the temperature distribution characteristics of the solid wall radiant panel after heat exchange with the air film.The results show that the increase of the length of the air supply outlet will reduce the momentum of the air film per unit area,and the heat transfer efficiency of the solid wall radiation plate and the air film will be reduced accordingly.(3)Establish an office model with personnel activities,and numerically simulate the temperature distribution of solid wall radiant panels,radiation heat transfer effects and the effect of radiation convection air conditioner utilizing air film and solid wall heat exchange on indoor velocity distribution,temperature distribution,and humidity distribution under summer conditions.And the result of its effect on indoor environment is compared with that of traditional wall mounted convection air conditioner.It is found that the radiation convection air conditioner utilizing air film and solid wall heat exchange can transfer 8.4% of the cooling capacity of the air-conditioning supply air to the personnel area,and create a relatively comfortable environment combined with the wind speed distribution and relative humidity distribution that meet the design requirements.(4)In winter,the temperature distribution of the solid wall radiant panel,the heat transfer effect and the effect of the air conditioner on the indoor velocity distribution and temperature distribution are analyzed by numerical simulation.The results are compared with the effect of the traditional wall mounted convection air conditioner on the indoor environment.The results show that the distribution of wind speed is uniform and the indoor temperature distribution is closer to the design requirements.