Consider the plasma spraying process of Problems 5.25 and 7.75. For a nozzle exit diameter of D = 10 mm and a substrate radius of r = 25 mm, estimate the rate of heat transfer by convection, q_conv, from the argon plasma to the substrate, if the substrate temperature is maintained at 300 K. Energy transfer to the substrate is also associated with the release of latent heat, q_tar which occurs during solidification of the impacted molten droplets. If the mass rate of droplet impingement is lip = 0.02 kg/s ∙ m², estimate the rate of latent heat release.