Experimental Study On The Absorption Refrigeration Performance And Numerical Simulation On Falling Film Of [EMIM][DMP]+H₂O Solution

The absorption refrigerating apparatus and heat pump that can increase the grade of heat source are widely used in industry. The absorber, the core of the absorption refrigerating, directly determines the performance of the entire system, which is the focus of the entire absorption refrigerating apparatus research. Also the working pairs have a direct impact on the absorption refrigerating apparatus. In industry, lithium bromide solution and ammonia solution are the commonly used working pairs. However, LiBr solution could be easily crystallized and corroded while ammonia highly risky. Therefore, the development of new working pairs is practically valuable.Ionic liquids, as the most popular research material with good absorption, non-crystalline and non-corrosive characteristics can meet the requirements of the absorption refrigerating apparatus. However, the ionic liquid is not used into absorption refrigerating apparatus, due to the lack of study with different operating and physical parameters.The present work has an in-depth exploration in the following respects for the current incomplete study:First, an absorption refrigerating apparatus was set up, then ionic liquid [EMIM][DMP]+H2O solution was adopted into circulate inside the apparatus. The performance of the entire device was analyzed. By comparing the theoretical and practical thermal coefficient and we concluded that [EMIM][DMP]+H2O can meet the requirement of working pairs.Secondly, the ionic liquid [EMIM][DMP]+H2O solution falling film outside the smooth tube was simulated. [EMIM][DMP]+H2O solution with LiBr solution flow pattern was studied. The surface tension, viscosity and inlet velocity was changed as a comparison. It was concluded that surface tension can affect the distribution of inertia waves. The smaller surface tension is, the bigger inertia wave becomes. Viscosity affects the waveform and velocity of inertia waves. When viscosity reaches a certain value, inertia wave will disappear and have a very low velocity. When the inlet velocity is large enough, the droplet will "splash" out.Finally, the ionic liquid [EMIM][DMP]+H20 solution falling film outside the corrugated tube was studied. The effect of waves on the entire section of the corrugated tube was studied. It was found that film can uniformly wet the tube, the corrugated tube will affect the flow of liquid film and produce smaller swirls, which can promote the internal components and energy exchange, which is favorable for the absorption effect.