Application Research On Heat Pipes Adsorbent Bed In Ship Solid Adsorption Refrigeration System

Issues of environment and energy are two main problem areas presently confronting the world.As society progresses and economies develop,saving energy and protecting the environment have become issues of international significance.Adsorption refrigeration system is a kind of environmentally friendly refrigeration system,which can be driven directly by low grade energy such as solar energy and industrial waste heat,and it poses no danger to the environment,so adsorption refrigeration technology has received more and more attention in recent years.The exhaust gas temperature of ship is commonly more than 400℃,which contains quantity of heat,occupying more than thirty percent of the fuel energy. However,the ship needs more refrigeration.The application of adsorption refrigeration to recovery of engine exhaust heat is also attractive and significant to the international social economy.Currently the heat transfer performance of the adsorbent bed is very bad and the adsorption refrigerating system efficiency very low and this restricts the application of adsorption refrigerating.This paper presents a method using heat pipes to enhance the heat transfer performance of the adsorbent bed,and to improve the adsorption refrigerating system efficiency.This paper has calculated the flux and energy of diesel exhaust gas according to the parameter of ship SITC—YOKOHAMA,and also calculated the dimension of the adsorbent bed and the mass of work pairs.It then presents a design for a new kind of heat pipe adsorbent bed.Furthermore,the paper also calculates the size of other parts of the adsorption refrigerating system such as condenser,evaporator,pipeline.The heat transfer performance and temperature field of the heat pipe adsorbent bed were simulated and analyzed according to the principle of temperature distribution varying with time.The simulation results indicated that the temperature of most area in the adsorbent bed was very high and distributed uniformly,the temperature gradients was very little,the adsorbent bed met the disadsorption temperature.This study also simulated and compared many parameters that affect the heat transfer performance of the adsorbent bed.The results indicated that the coefficient of heat conductivity,the density and the specific heat of the adsorbent have important effect on the temperature of the adsorbent bed;the performance of heat transfer of cylindrical adsorbent bed is better than rectangular,and the ellipse heat pipe is better than rotundity pipe;minimising the diameter of heat pipe and increase the number of heat pipe can improve the heat transfer performance of the adsorbent bed;the wing piece on heat pipe can also enhance the heat transfer performance of the adsorbent bed.The thesis investigated parameters that affect the heat transfer performance of the adsorbent bed,which supplied the theoretical analyses to the optimal design of the adsorbent bed and also has made base for application of solid adsorption refrigeration.