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Introduction: The simplest type of heat exchanger consists of two concentric pipes of different diameters, called the doublepipe heat exchanger. One fluid in a double-pipe heat exchanger flows through the smaller pipe while the other fluid flows through the annular space between the two pipes. Two types of flow arrangement are possible in a double-pipe heat exchanger: in parallel flow, both the hot and cold fluids enter the heat exchanger at the same end and move in the same direction, as shown in Figure 1-1A. In counter flow, on the other hand, the hot and cold fluids enter the heat exchanger at opposite ends and flow in opposite directions, as shown in Figure 1-1B. Parallel Pipe (aluminum inner tube) Aluminum inner tube with copper outer tube Overall length OveralllengthInnerTubeOuterTubeL=1.21m(48in)D0=15.875103m(0.625in)Di=12.60103m(0.496in)Ao=60.81103m2(0.654ft2)heattransferareaD0=22.23103m(0.875in)Di=19.94103m(0.785in) Inner Tube Heat Exchanger Demonstrator Layout: Hampden Model H-6878 6-Pass Heat Exchanger 1. Drains 9. Flowmeter 18 3-Way diverter vaivg 2. Cold water inlat 10. Power cord \& cord wrap 19. 3-Way value 3. Check valve 11. Stream inlet 20. Shell and uube heat axchanger 4. Hot water filet 12. Temperalure display 21. Ball valves 5. Mixigg valve 19. Power of indlcator 22. Extemal thermocouple jacks 14. Main power clrculi breakar 23. Cooper tube 6. Flowmeter 15. 0Njoff valve (13 tolal) 24. Parallel pipe heat exchanger 7. Flow control valve 16. Cross flow heat exchanger 25. 3-Way valve 8. Thermocouple selector switch 17. Thermacouple (25 total) 26. Flow control valve Parallel Pipe Heat Exchanger (Aluminum - Parallel Flow) Hot water flow rate =2.02gal/min Cold water flow ratte =1.00gal/min Cold water flow rate change to 3.98gal/min Parallel Pipe Heat Exchanger (Aluminum - Counter Flow) Hot water flow rate =2.02gal/min Cold water flow rate =1.00gal/min Cold water flow rate change to 4.02gal/min Using the recorded data, and the Heat Exchanger Demonstrator Data calculate, for each set of flow rates, and for both parallel and counter flow: 2. The Logarithmic Mean Temperature Difference, in C, using: Tm=ln[(Th1Tc1)(Th2Tc2)](Th2Tc2)(Th1Tc1) for parallel flow and counter flow for each set of flow rates