Problem #5: The attic space of a home contains a water heater having a capacity of...

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Problem #5: The attic space of a home contains a water heater having a capacity of 55 gallons and a tank diameter of 2 ft. For maintenance purposes, the tank must be drained of water once a year. To assist with draining, a hydraulic-smooth ( = 0) garden hose having an overall length of 50 ft and an internal diameter of 5/8 inches is connected to the drain port of the water heater as shown below. A breather" valve is opened on top of the water heater so the water surface inside will be at atmospheric pressure while draining. The flow of water (60 F) through the garden hose will assumed to be viscous, where the friction factor fis given by either the Colebrook equation or Moody Chart, and a minor loss coefficient of K = 0.5 is assumed for the inlet connection of the pipe to tank. Determine: a) Determine the initial water velocity including the major and minor viscous losses (ft/s), b) Assuming the flow rate remains constant and equal to the initial value, determine the time required to drain the tank (min) c) Extra Credit (2 points for answer correct to three significant digits). Accounting for the change in liquid height in tank and changing viscous pressure losses, determine the time required to drain the water tank (min)* *Note: you may use a computer spreadsheet program or other software to solve part e. Your answer should be computed to accuracy of three significant digits. Water Supply Valve (closed) Water Heater 11ft 55 Gal. 2 ft dia. Hot water output (closed while draining) Drain port Attic space Ground level Garden hose 50 ft length x 5/8" Dia. (inside) Problem #5: The attic space of a home contains a water heater having a capacity of 55 gallons and a tank diameter of 2 ft. For maintenance purposes, the tank must be drained of water once a year. To assist with draining, a hydraulic-smooth ( = 0) garden hose having an overall length of 50 ft and an internal diameter of 5/8 inches is connected to the drain port of the water heater as shown below. A breather" valve is opened on top of the water heater so the water surface inside will be at atmospheric pressure while draining. The flow of water (60 F) through the garden hose will assumed to be viscous, where the friction factor fis given by either the Colebrook equation or Moody Chart, and a minor loss coefficient of K = 0.5 is assumed for the inlet connection of the pipe to tank. Determine: a) Determine the initial water velocity including the major and minor viscous losses (ft/s), b) Assuming the flow rate remains constant and equal to the initial value, determine the time required to drain the tank (min) c) Extra Credit (2 points for answer correct to three significant digits). Accounting for the change in liquid height in tank and changing viscous pressure losses, determine the time required to drain the water tank (min)* *Note: you may use a computer spreadsheet program or other software to solve part e. Your answer should be computed to accuracy of three significant digits. Water Supply Valve (closed) Water Heater 11ft 55 Gal. 2 ft dia. Hot water output (closed while draining) Drain port Attic space Ground level Garden hose 50 ft length x 5/8" Dia. (inside)