Question

Problem 7.075 An air-cooled steam condenser is operated with air in cross flow over a square, in-line array of 400 tubes (N N-20), with an outside tube diameter of 20 mm and longitudinal and transverse pitches of s 60 mm and sr 84 mm, respectively. Saturated steam at a pressure of 2.455 bars enters the tubes, and a uniform tube outer surface temperature of T,-390 K may be assumed to be maintained as condensation occurs tudy ithin the tubes. (a) If the temperature and velocity of the air upstream of the array are T,-300 K and v-4 m/s, what is the temperature T, of the air that leaves the array? As a first approximation, evaluate the properties of air at 300 K. (b) If the tubes are 2 m long, what is the total heat transfer rate for the array? What is the rate at which steam is condensed in kg/s? Step 1 What is the maximum velocity of the air as it flows between the tubes, in m/s? the tolerance is +/-596 By accessing this Question Assistance, you will learn while you earn points based on the Point Potential Policy set by your instructor Step 2 What is the average Nusselt number for the air flow over this tube the tolerance is +/-5% By accessing this Question Assistance, you will learn while you earn points based on the Point Potential Policy set by your instructor Attempts: 0 Step 3 What is the temperature of the air leaving the array of tubes, in K? the tolerance is +/-596 the tolerance is +/-590 By accessing this Question Assistance, you will learn while you earn points based on the Point Potential Policy set by your instructor. Attempts: 0 of 3 used SAVE FOR LATER SUBMIT ANSWER Step 5 What is the total heat transfer rate for the array, in W? 95 the tolerance is +/-590 By accessing this Question Assistance, you will learn while you earn points based on the Point Potential Policy set by your instructor. Attempts: O of 3 used SAVE FOR LATER SUBMIT ANSWER Step 6 What is the rate at which steam is condensed, in kg/s? kg/s the tolerance is +/-590 By accessing this Question Assistance, you will learn while you earn points based on the Point Potential Policy set by your instructor. Attempts: 0 of 3 usedSAVE FOR LATER SUBMIT ANSWER SUBMIT ANSWER

Answer 1

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