Two thin radiation shields with emissivities of ε3= 0.1 and ε4= 0.15 on both sides are - placed between two very large parallel plates, which are maintained at uniform temperatures t= 600 k and t2=300 k and have emissivities ε1= 0.6 and ε2= 0.7, respectively. determine a)- the net rates of radiation heat transfer between the two plates with and without the shields per unit surface area of the plates. b)- the temperatures of the radiation shields in steady operation

For the closed feedwater heater below, feedwater enters state 3 at a pressure of 2000 psia and temperature of 420 °f at a rate of ix10 ibhr. the feedwat extracted steam enters state 1 at a pressure of 1000 psia and enthalpy of 1500 btu/lbm. the extracted er leaves at an enthalpy of 528.7 btu/lbm steam leaves as a saturated liquid. (16) a) determine the mass flow rate of the extraction steam used to heat the feedwater (10) b) determine the terminal temperature difference of the closed feedwater heater

The drive force for diffusion is 7 fick's first law can be used to solve the non-steady state diffusion. a)-true b)-false

Assuming compressible flow of air and that the measurements are done at flagstaff a pitot static tube that gives the difference of total and static pressure measures 0.35 m of mercury. what is the velocity of air? assume the temperature to be 300k. (submit your excel or matlab calculation sheet)