Problem Statement

Warm water at $318K$ is to be cooled to $303K$ by countercurrent contact with air in a tower packed with wood slats. The inlet air has a dry$-$bulb temperature of $304K$ and a wet$-$bulb temperature of $295K.$ The mass flow rate of water is $100k\frac{g}{m^2}$min and the air used is $1\mathrm{.}3$ the minimum.

Consider that $h_{\text{l}\text{l}\text{c}\text{o}\text{r}\text{n}\text{e}\text{r}}\frac{a}{k}{r}_{r}a=-12\mathrm{.}61$

Calculate:

a$.$ The dry air flow rate to be used.

b$.$ The height of packing if $H_t=0\mathrm{.}54m$