Adiabatic Evaporation Research Articles

Effect of droplet size distribution on spray drying kinetics

A comparison is made between the processes of adiabatic evaporation of a polydisperse system of droplets and a monodisperse system with droplets equal in size to the largest droplet of the polydisperse system. The process takes place in air with the same initial and final parameters in both cases.

On the Driving Force, (H<SUB>w</SUB>-H)

The traditional approximation, brings appreciable error with a slight raising of temperature or humidity of gas. Its numerical value in the adiabatic vaporization (cooling of gas) process is shown in Fig. 1. In an example of counter-current, constant-rate drying (adiabatic cooling) process, the required contact area has been given by A4, accompanying an error shown in Fig. 2, when ψ2=80%. Correct one is A1 of Eq. (6).The authors propose the new approximation, Eq. (2) or A2, instead of Eq. (4) or A4, by which the error becomes smaller by one order and to be within the safety range. Their comparison can be made by Fig. 2 & 4.This paper will have a relation to the discrussion about the accuracy of the Lewis' law, h/k'=CH. And the future precise investigation obout kG=f(G'), will attract the researchers' attention to the conversion erfor of kG to k'.In the case of taking kG as constant against instead of (ps-p), Eq. (3) will be better suited.