Experimental Investigation of Condensation Heat Transfer in Ammonia Evaporative Condensers

Abstract

This paper reports experimental data obtained for ammonia condensation heat transfer in an evaporative condenser. Experiments were carried out on a specially designed set-up equipped with both measuring and control devices, and a data acquisition system. Experiments were conducted for ammonia saturation temperature of 22°C to 40°C and condenser heat rejection rate ranging from 2000W to 6000W, during steady state condensation of ammonia. The experimental investigation aimed to determine thermal performances of the ammonia evaporative condenser under different operating conditions, namely as a function of: temperature difference between ammonia condensation and inlet air wet bulb temperature, cooling water mass flow rate and ammonia mass flow rate. Water film temperature distribution along the condenser's height has also been studied. Experimental results have been further compared to data in the open literature by authors with similar experimental investigations. The paper concluded that experimental results are in fairly good agreement with other authors work and consequently reliable. The paper also addresses the current ecological aspect implied by refrigerants, by using ammonia. Apart from its attractive thermo-physical properties, as compared to HFCs, ammonia is also an environment friendly natural refrigerant, known for its zero ozone depleting potential and zero global warming effect.