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ChE 306: HEAT TRANSFER SPRING 2016 – SOLUTIONS Homework #8: Heat Exchanger Software; Radiation (60 points + 10 BONUS points) DUE: WEDNESDAY, April 27, 2016, in class OFFICE HOURS/HW HELP: Mon 3-4:30 & Thurs 10-11 (HM Comer 339A), Tues 4/26 2:30-3:30 (Nicolette Hook, HM Comer 341) HW Help session: Tues 4/26 5:00 pm (HM Comer 337) TEAMS: For this HW set you can work INDIVIDUALLY or in a TEAM of 2 (TWO) maximum. A single assignment can be turned in by up to 2 team members. Include all team members’ names on the HW set when turning in. Each team member should understand how to solve ALL problems. SOFTWARE:See class notes on downloading or accessing the software “Heat Exchanger.” A Frequently Asked Questions (FAQ) sheet is available on Blackboard in the same folder as the software download. HOMEWORK SETS: Turn in all problems, in the order they were assigned. Staple, if possible, and fold the set in half lengthwise. Write your name (all team member names) on the outside fold, so that it will be easy to return. FORMATTING: Work neatly, draw a diagram of the problem, where appropriate, keep problems in the correct order; if the grader can’t find a problem, then it may be scored a zero. Write on only one side of each sheet of paper. Engineering paper is NOT required. LATE HOMEWORK: Homework will not be accepted late. Turn it in during class, send it with a classmate, or drop it in the plastic folder outside my HM Comer office door BEFORE the solutions post on Blackboard (~ Noon on class days). If you have an excused absence for a homework set, I will drop that set, and award a score of 0 out of 0. 1. (30 pts) Using the software “Heat Exchanger”: Design the following 3 heat exchangers to get within +/- 1 oF of the targeted outlet temperature: A. A double pipe heat exchanger to heat 200 psi kerosene from 70 to 130 oF. The flowrate of kerosene is 2500 lb/h. Optimize the exchanger to use the smallest flow rate of utility fluid, which is lake water at 180 oF (which requires a fouling factor associated with the lake water of 0.0009 h-ft2-oR/Btu). Assume the water is also pressurized to 200 psi. The maximum pressure drop allowable in your design is 50 psi (for either fluid in the double pipe). Use counter-flow (the software doesn’t calculate heat transfer for parallel or cocurrent flow). Discuss how the following parameters in the heat exchanger software affect the heat transfer, and give the rationale for your selections: - inside and outside pipe diameter - tube material of construction - thickness of tube - which fluid to put in annulus vs. which in core B. A shell and tube heat exchanger to cool a 120,000 lb/h stream of hydraulic fluid from 135 to