An open wall consist in succession layer of fire bricks (Kf=1.21j/m²°C) a layer of lagging bricks(Kl=0.08j/m²°C) and a layer of bricks (Kb=0.6m²°C)each layer is 10cm thick, the temperature in the inside of the wall is 872°C ,on the outside 32°C. calculate the following (a)heat lost by conduction every 12 hours if the surface area of the wall is 20 m² (b) temperature in the middle of the layer of lagging bricks (c)overall heat transfer coefficient

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 flow rate of air through a through a pipe is 0.02 m5/s. a pitot static tube is placed in the flow. the radius of the pitot static tube is 1 mm. assuming the flow to be steady and the air to be at 300k, calculate the difference in total and static pressure if the diameter of the pipe is: (a) d 0.1 m d 0.05 m (c) d 0.01 m

Asimple rankine cycle uses water as the working fluid. the water enters the turbine at 10 mpa and 480c while the condenser operates at 6 kpa. if the turbine has an isentropic efficiency of 80 percent while the pump has an isentropic efficiency of 70 percent determine the thermal efficiency