Question: ( 3 0 points ) To support a power station cooling system set up after a hurricane, ethylene glycol must be chilled to 3 0

(30 points) To support a power station cooling system set up after a hurricane, ethylene glycol must be chilled to 307 K or less in a counterflow heat exchanger. Seawater is available at 284 K and at a flow rate of 17 liters per minute [l/min]. The ethylene glycol passes through the pipe annulus with a convection heat transfer coefficient of 2100Wm2*K and a flow rate of 91min. For the seawater, use properties for water at 300 K . For the ethylene glycol, use properties at 370 K . Assume that all heat transfer goes from the ethylene glycol to the seawater.
Tc,i=28
a. Use the Eftectiveness-Number ot I ranster Units (-NIU) method to determine the overall heat transfer coefficient or UA [W/K] of the counterflow heat exchanger required for this chilling process.
b. Based on an applicable correlation from Table 8.4, what is the convection heat transfer coefficient Wm2*(K) of the water flowing through the inside of the pipe? Assume fully developed flow and smooth pipe walls, and neglect fouling of the seawater.
c. Based on the total resistance, determine the length [m] of pipe needed for this counterflow heat exchanger. Assume that the pipe wall separating the two fluids is thin.
d. What is the outlet temperature [K] of the water?
e. Present an engineering estimate for Size m3, Weight [kg], and Power [kW](SWaP) as well as a cost estimate [$] for the ethylene glycol pump and the driving motor. Indicate the type of pump recommended for this application. Account for the major losses (smooth pipe) and minor losses (one well rounded entrance, four 90 flanged elbows, one well rounded exit).
f. Present an engineering estimate for Size [m^3], Weight [kg], and Power [kW](SWaP) as well as a cost estimate [$] for the seawater pump and the driving motor. Indicate the type of pump recommended for this application. Account for major losses (smooth pipe) as well as a 25 m elevation change required to move seawater from the waterline of the ship to the deck level.
Hint: For e. and f., refer to the Mechanical Energy Form (Head) of Conservation of Energy for a Steady, One-Inlet, One-Exit Control Volume. Use the hydraulic diameter of the ethylene glycol tube. Online references for SWaP are encouraged, e.g.. find a Commercial Off The Shelf (COTS) item.
( 3 0 points ) To support a power station cooling

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