Aconverging nozzle has an exit area of 0.007 m^2 . nitrogen stored in a reservoir is to be discharged through the nozzle to an ambient pressure of 101.3 kpa. determine the flow rate through the nozzle for absolute reservoir pressures of 138 kpa, and 700 kpa. assume isentropic nozzle flow. in each case, determine the increase in mass flow to be gained by reducing the back pressure from 101.3 kpa to 0 kpa. reservoir temperature =289 k.

A3-mm-thick panel of aluminum alloy (k 177 w/m-k, c 875 j/kg-k and ? = 2770 kg/m) is finished on both sides with an epoxy coating that must be cured at or above t,-150°c for at least 5 min. the production line for the curing operation involves two steps: (1) heating in a large oven with air at ts,0-175°c and a convection coefficient of h, 40 w/m2. k, and (2) cooling in a large chamber with air at 25°c and a con- vection coefficient of he 10 w/m2.k. the heating portion of the process is conducted over a time interval te which exceeds the ime required to reach 150°c by 5 min (h = r + 300 s). the coating has an emissivity of ? = 0.8, and the temperatures of the oven and chamber walls are 175 and 25°c, respectively. if the panel is placed in the oven at an initial temperature of 25°c and removed from the chamber at a safe-to-touch tempera ture of 37°c, what is the total elapsed time for the two-step curing operation?

Agas is compressed from vi 0.3 m, p 1 bar to of v2 0.1 m3, p2--3 bar. pressure and volume are related linearly during the process. for the gas, find the work, in kj.

Determine the stoichiometric and actual air-fuel ratios and the mole flue gas composition for combustion with 15% excess air for raw indiana, pennsylvania raw coal.