Adiabatic water absorption properties of an aqueous absorbent at very low pressures in a spray absorber

Abstract In this paper, spray absorber in absorption chillers, a new technique is proposed. This concept of atomization increases the heat and mass transfer rates due to the increases of the expose area of the brine solution compared to falling film technique used in the conventional absorber. Results presented in this paper show the great enhancement of water absorption property by having a pressure atomization. The experimental set up was included a single nozzle adiabatic spray chamber operating at the design pressure, a solution circulating and tempering system, a Laser measurement system to measure the size and the velocity of the droplets, and data acquisition and control system. Based on a first principle “Newman model”, an analytical model was developed to predict the enhance transfer rates. These analytical results were compared with the experimental results that showed good agreement. The experiments were conducted by varying the differential pressure across the nozzle and the liquid desiccant flow rate. The dimensionless viscosity ratio, k , of this disperse/continuous phase flow was around 1300. The nozzles tested were able to produce the expected drop sizes and mean drop velocities. The droplet Reynolds number and Peclet number varied from 10 to 1500 and 0.005 to 0.5, respectively.