Question: Consider a 1.2 m square wet towel hanging from a clothes line. Let sunlight fall on one side at an angle of 45°. The normal solar flux is 946W/m2, and the absorptivity and emissivity of the towel are 1. The surrounding air is at 21°C, with a relative humidity of 65 percent. At the equilibrium temperature of the system it is determined that an equivalent system with no mass transfer would have a free-convection coefficient of 8.5 W/(m2 . K). What is the drying rate during the period when the towel is sufficiently wet that the surface can be idealized as a liquid surface?