The average heat transfer coefficient for air flow over an odd-shaped body is to be determined by the mass transfer measurements, using the similarity between heat and mass transfer. The experiment is conducted by blowing dry air over a body covered with a layer of naphthalene (MW 128 kg kmol-1) The surface area of the body is 0.8 m2 and it is observed that 125 g of naphthalene has sublimated in half an hour. During the experiment, both the body and the air were kept at 27 oC and 1 atm pressure. Under these conditions, the saturation vapour pressure and mass diffusivity of naphthalene are 11 Pa and 0.61 x 10-5 m2s-1 respectively.

Use your understanding of the similarity between heat and mass transfer to estimate the coefficient for heat transfer between the surrounding air and the solid under these flow conditions?