# Double Pipe Heat Exchanger

## Double Pipe Heat Exchanger

Lab #4* – *Double Pipe Heat Exchanger Introduction: Procedure: Step #1: Open up valves 11 and 13, and make sure that valves 10 and 12 are entirely closed. This will give you the proper flow setup for the parallel flow measurements. Step #2: Set the hot water flow rotameter to a % reading of 26, this 26% flow rate represents an actual flow rate of 0.2 CFM for the how water. This flow rate will be good for the first four conditions in which temperature readings will be recorded for this experiment. Step #3: Set the cold water flow rotameter to read 0.2 CFM as the flow rate. For this first setup condition you should wait 10 minutes for the heat exchanger to reach steady state conditions. Step #4: Turn the knob on the heat exchanger for the digital readout to get the values for each of the six thermocouple locations in the double pipe heat exchanger. For the parallel flow readings T1=hot water midpoint, T2=cold water midpoint, T3=cold water inlet, T4=hot water inlet, T5=hot water outlet, and T6=cold water outlet. Be sure to record each value and keep track of the location in the heat exchanger that the temperature reading is coming from. Step #5: Change the cold flow rate to a rotameter reading of 0.4 CFM. Step #6: Wait 3 minutes and then repeat the recording of the data as discussed in step #4. Step #7: Repeat steps #5 and #6 for cold water rotameter readings of 0.6 and 0.8 CFM and be sure to record all the data. Step #8: Set the hot water rotameter to a reading of 52% (0.4 CFM), then repeat steps #3 thru #7 for this configuration. After all data was been recorded proceed to step #9. Step #9: First turn the hot and cold water rotameters to both have flow rates of 0.2 CFM, then completely close valves 11 and 13, then open valves 10 and 12 all the way. This completes the proper arrangement for the counter flow heat exchanger. Now wait five minutes for this new system setup to reach thermal equilibrium. Step #10: Record the values for each of the...