A heat recovery device involves transferring energyfrom the hot flue gases passing through an annular
region to pressurized water flowing through the innertube of the annulus. The inner tube has inner and outerdiameters of 24 and 30 mm and is connected by eightstruts to an insulated outer tube of 60-mm diameter.
Each strum is 3 mm thick and is integrally fabricatedwith the inner tube from carbon steel
Consider conditions for which water at
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- In a large student house supply at a pressure of 2 bar, gauge, and at a temperature 10°C. A wash basin cold tap is located 3 meters above the mains supply, connected to the mains pipe with a copper pipe of internal diameter 15 mm and length 12 meters. When the tap is opened the flow rate of water out of the tap is 24 litres per minute, creating a Fanning friction factor in the pipe of 0.008. cold water is supplied by the mains water a) Calculate the Reynolds number of the water in the pipe and determine if it is laminar or turbulent. b) Calculate the pressure loss from friction, change in elevation, and hence the pressure of the water just before entering the tap. c) Name two assumptions that have been made in order to arrive at your answer to part b) and state if these assumptions under or over predict the pressure of the water just before entering the tap. d) If the value were not given, what procedure would be needed to determine the Fanning friction factor?arrow_forward3. A 6 in x 20 ft uninsulated B.I pipe conveys steam at 385 °F with an average ambient temperature of 85°F. if the cost of the fuel is PhP 250.00 per 106 BTU with the net energy conversion efficiency of 75%, what is the annual cost of the heat lost? For 6 in. pipe schedule 80:Do = 6.625 inDi = 5.761 in For iron:k = 30 BTU/ hr ft °F for the surface coefficients:hi = 1000BTU/ hr ft2°F ho = 2 BTU/hr ft2 °Farrow_forwardConduction 1. A thermodynamic analysis of a proposed Brayton cycle gas turbine yields P= 5 MW of net power production. The compressor, at an average temperature of T. = 400°C, is driven by the turbine at an average temperature of T₁ = 1000°C by way of an L = 1m-long, d= 70mm - diameter shaft of thermal conductivity k = 40 W/m K. Compressor min T Combustion chamber Shaft L Turbine Th out (a) Compare the steady-state conduction rate through the shaft connecting the hot turbine to the warm compressor to the net power predicted by the thermodynamics- based analysis. (b) A research team proposes to scale down the gas turbine of part (a), keeping all dimensions in the same proportions. The team assumes that the same hot and cold temperatures exist as in part (a) and that the net power output of the gas turbine is proportional to the overall volume of the device. Plot the ratio of the conduction through the shaft to the net power output of the turbine over the range 0.005 m s Ls 1 m. Is a…arrow_forward
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- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning