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DAQ Calibration for Heat Exchanger Calibration of Cold/Hot Flow Rate and Temperature. UTC ENCH/ENEV 435 11/25/03 Greg Kirton Kevin Zitzow Phuong Mai. Objectives. Calibrate Cold Water Flow Rates from DAQ with Measured Flow Rates
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DAQ Calibration for Heat ExchangerCalibration of Cold/Hot Flow Rateand Temperature UTCENCH/ENEV 43511/25/03 Greg Kirton Kevin Zitzow Phuong Mai
Objectives • Calibrate Cold Water Flow Rates from DAQ with Measured Flow Rates • Calibrate Hot Water Flow Rates from DAQ with Measured Flow Rates • Calibrate Temperatures from DAQ with Measured Temperatures
Schematic of Heat Exchanger FT=Flow Transmitter S=Solenoid TT= Temp Transmitter CW=Cold Water W/H=Water Heater CWS=Cold Water Supply CWR=Cold Water Return
Procedure for Measurements • A stopwatch was used to keep time • A 1000 ml graduated cylinder was used to measure volume • Measured volume of water obtained in 10 seconds. • Varied • % Opening of Cooling Water Valve • % Hot Water Pump Speed • 4 measurements were made for each setting
Data Analysis • Measurements were averaged and error was calculated using student’s T equation. • http://chem.engr.utc.edu/engr329/Lab-manual/Students-T.htm • Computer DAQ was averaged and standard deviation was calculated in Excel • DAQ error was reported as 2xSTDEV
Tube Side Port A Shell Side Port A Shell Side Port B Tube Side Port B
Objectives • Compare total heat transfer rates of the hot and cold streams. • Determine the overall heat transfer coefficient.
Pictures of the Heat Exchanger Cold water in Tube bundle Hot water in
Heat Transfer Properties • 55 tubes • Tube Volume = 143 cc • Tube Length = 506 mm • Total heat transfer area = 0.27 m2
Heat Transfer Diagram Thot,out Thot,in q Tcold,in Tcold,out
1st Run • Input = 75% • Hot water mass flow rate (HWS) of 0.4124kg/s • CW valve open = 60 % • Cold Water mass flow rate (CWS) of 0.080kg/s
q and U Results of 1st Run • qc =5.76 kW • qh = 3.37 kW • Uc = 1352 W/m2K • Uh= 792 W/m2K
2nd Run • Input = 40% • Hot water mass flow rate (HWS) of 0.0258 kg/s • CW valve open = 40 % • Cold water mass flow rate (HWS) of 0.0505 kg/s
q and U Results of 2nd Run • qc =2.33 kW • qh = 2.25 kW • Uc = 532 W/m2K • Uh= 514 W/m2K
Cold Flow Hot Flow 1st 1st 2nd 2nd 1). HWS = 0.04124kg/s and CWS = 0.080 kg/s 2). HWS = 0.0258 kg/s and CWS = 0.0505 kg/s
Hot Flow Cold Flow 1st 1st 2nd 2nd 1). HWS = 0.04124kg/s and CWS = 0.080 kg/s 2). HWS = 0.0258 kg/s and CWS = 0.0505 kg/s
Conclusions • 1st run: qc and qh are not closed. • 2nd run: qc and qh are closed. • 1st run: Uc and Uh are not closed. • 1st run: Uc and Uh are closed. • U increases as HWS and CWS increase. 1). HWS = 0.04124kg/s and CWS = 0.080 kg/s 2). HWS = 0.0258 kg/s and CWS = 0.0505 kg/s
Questions ?????