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A model has been developed based on Colburn–Drew type formulation to analyze a vertical tube in tube stainless steel generator with forced convective boiling. Desorption of refrigerant vapor from refrigerant–absorbent solution takes place in the inner tube of the generator, when hot water through the annulus is used as heating medium. Simultaneous heat and mass transfer phenomena of desorption are described mathematically using the mass and energy balances, considering the heat and mass transfer resistances in liquid as well as vapor phases. Model equations are solved simultaneously by means of initial value problem solvers using explicit Runge–Kutta method with 4th order accuracy. A computer code has been developed in MATLAB to obtain the results. A parametric analysis has also been performed to study the effect of various parameters on the performance of the generator.

In the present era, the refrigeration and air conditioning have become essential requirements, and consume significant portion of energy available. The refrigeration requirements are severe in the hot and humid countries and, the refrigeration systems based upon solar energy are desirable. This study focuses on the thermodynamic modelling of ammonia water diffusion absorption refrigeration cycle with helium as pressure equalizing gas. The performance of the cycle is investigated parametrically by computer simulation based on thermodynamic modeling. It is found that the performance shows a loss of 37.36% at 110${}^{\circ }$C while only 23.52% at 140${}^{\circ }$C a generator temperature in the range of 120 to 150${}^{\circ }$C is best suited for ammonia concentration range of 0.25–0.45 to get optimum performance.

The absorption refrigeration device and the adsorbent refrigeration device are the usual cooling methods driven by the use of diesel-generator waste heat. In this paper, the discussion of the two methods is developed on the selection of system types, the utilization efficiency, the match methods of the cooling capacity, as well as the issues to be solved. Through calculation and comparison: it's found that absorption refrigeration device produces more cooling capacity from waste heat recovery, for which the waste heat of flue gas could be used directly, and double-effect unit could be adopted; for adsorbent refrigeration device, the cooling capacity is able to be improved by recovering the waste heat of cooling hot-water together with the waste heat of hot water which is converted from the waste heat of flue gas.