Research On The Characteristics Of Double-stage Lithium Bromide Bubble Pump Refrigeration System With Different Diameters

Nowadays fossil fuels account for a major part of the energy consumption.With the continuity decrease of fossil fuels inventory,the researches of sustainable energy and improving the utilization of fuels has gained more and more attention.Especially for the energy intensive shipping industry for the energy intensive shipping industry waste heat refrigeration,saving high quality electric energy and fully using the ship's waste heat have become an important direction of ship cooling.Bubble pump absorption refrigeration,with no mechanical pump and pollution,has gained more and more attention.This paper studied the characteristics of the bubble pump and the coupling characteristics of the bubble pump with double-stage different diameters and absorption refrigeration system.The main work include the characteristics of bubble generation,bubble lifting movement within the tube,aqueous solution of lithium bromide as refrigerants as well as the absorption refrigeration system driven by the bubble pump with double-stage different diameters.Using high-speed cameras and infrared cameras,the paper studied the bubble pump operating state of each part.The bubble generation and movement of the container as well as temperature distribution in each state.This paper analyzed several factors including the radius of bubbles from,Air bubbles from the contact angle,the bubble pump starting time which can influence the main characteristics of bubble pump by combining experiments and theories.By setting a lithium bromide absorption refrigeration system test bench driven by the bubble pump,this paper studied the effect of different-diameter bubble pumps,heating power and solute concentration on the whole refrigeration system.There results show that the cooling index and COP values of the different-diameter bubble pump are larger than the same-diameter bubble pump.Comparing the different-diameter bubble pump of 9.5mm-6.5mm and 9.5mm-9.5mm under the same condition,it was found that the cooling capacity of the former was bigger,which means a smaller second-stage diameter pump acts better compared with same first-stage diameter,the increase was 8.9%-16.5%;The cooling capacity of the pump of 12mm-9.5mm was similarly bigger than the pump of 9.5mm-9.5mm.