AN EXPERIMENTAL-STUDY AND A COMPUTER-SIMULATION OF HEAT AND MASS-TRANSFER FOR 3-DIMENSIONAL HUMIDIFICATION PROCESSES

The paper deals with a numerical and an experimental analysis of the h umidification process of air in a nearly horizontal tube. The numerica l analysis is based on a finite-difference solution of the three-dimen sional momentum, heat and mass transfer differential equations within the tube for the evaporation process of a water stream of circular men iscus cross-section counterflowing to an air stream. In order to provi de reliable, high-accuracy data to assist in the development of the th eoretical model, tests have been conducted using specially constructed apparatus to measure temperature and velocity profiles within the tub e. The proposed computer algorithm was validated by evaluating its abi lity to predict the measurements of temperatures and velocities along the stream's flow. The theoretical predictions agree well with the exp erimental data. The model may be used to give performance characterist ics for a wide range of humidification processes with different workin g fluids and state conditions.