Heat and mass transfer processes between a water spray and ambient air – II. Simulations

Abstract

Experimental data on evaporative cooling by water sprays was generated by Sureshkumar et al. [R. Sureshkumar, P.L. Dhar, S.R. Kale, Heat and mass transfer processes between a water-spray and ambient air – I. Experimental data, Appl. Therm. Eng. 28 (2008) 349–360] where uncertainties were reduced substantially. Four nozzle sizes were tested for hot-dry and hot-humid conditions that covered DBT from 35 to 47 °C, and R.H. 10–60% in parallel and counter flow configurations. Three water pressures 1, 2 and 3 bar(g) and three air velocities 1, 2 and 3 m s −1 completed the test matrix. A simulation model for two-way coupling of heat and mass transfer between the droplets and air is described here. Using the Maximum Entropy Formulation, droplet diameter–velocity combinations were generated and classified into 200 parcels that were the initial conditions for droplet motion. Simulation results and experimental data agree within ±15% for parallel and ±30% for counter flow configurations. Both, these experiments and simulations are improvements over the previous studies.