Radiation from the atmosphere or sky can be esti-mated as a fraction of the blackbody radiation corre-sponding to the air temperature near the ground, Tair.That is, irradiation from the sky can be expressed asand for a clear night sky, the emis-sivity is correlated by an expression of the form?sky?0.741?0.0062Tdp, where Tdpis the dew pointtemperature (C). Consider a flat plate exposed to the night sky and in ambient air at 15C with a rela-tive humidity of 70%. Assume the back side of theplate is insulated, and that the convection coefficienton the front side can be estimated by the correlation, where Tis the absolutevalue of the plate-to-air temperature difference. Willdew form on the plate if the surface is (a) clean andmetallic with ?? 0.23, and (b) painted with ??0.85?
Radiation from the atmosphere or sky can be esti-mated as
Problem 12.119 Chapter 12
Fundamentals of Heat and Mass Transfer | 0th Edition
- 2901 Step-by-step solutions solved by professors and subject experts
- Get 24/7 help from StudySoup virtual teaching assistants