APMP TC Fluid Flow Initiative Project Traceability Scheme Study for LPG Metering Progress Report at APMP 2011 TCFF Meeting Chun-Min Su, Ph.D. Center for Measurement Standards, ITRI Dec. 5, 2011

Copyright 2009 ITRI 工業技術研究院 Project Name –Traceability Scheme Study for LPG Metering Key Members –Overseer: Dr. Jiunn-Haur Shaw (CMS) –Co-Leader: Dr. Yoshiya Terao (NMIJ, TCFF Chair) –Collaborator: Dr. John Man (NMIA) Background and Objective of the Project –Transaction of LPG requires the support of sound national metrology scheme to ensure its fairness –Objective: to research on the traceability scheme for LPG transfer standard (TS) and correction factor based on the actual fluid (propane and butane) and water as working fluid, so that NMIs maintaining LPG legal measurement infrastructure could simplify the traceability method by utilizing water as test medium while keeping the same accuracy Project Budget and Its Use –US$6000, to be used in transportation of the TS, custom, meter testing, data analysis and training Project Overview 2

Copyright 2009 ITRI 工業技術研究院 Method Coriolis mass flow meter chosen as the transfer standard (TS) –Measures mass flow directly –Can be used for a variety of fluids under extended range of pressure (and temperature) –Capable of measuring fluid density Verify the flow measurement performance of the TS and, if necessary, identify possible method of correction –Calibrate the TS with different working fluid: water and LPG (propane and butane) –Calibrate the TS at different pressures Check the density measurement performance of the TS and establish the traceability 3

Copyright 2009 ITRI 工業技術研究院 The TS Package Micro Motion CMF050 mass flow meter with MVD transmitter, std. core processor –Maximum flow rate: 6800 kg/h = kg/min –Accuracy of mass flow: 0.1 % –Repeatability of mass flow: 0.05 % –Zero stability: kg/h –Accuracy of density: 0.5 kg/m 3 –Repeatability of density: 0.2 kg/m 3 Explosion-proof thermometer & pressure gauge 4 Cable Soft pad Loaned by Micro Motion free of charge for one year

Copyright 2009 ITRI 工業技術研究院 5 Small water flow standard calibration facility at CMS Temperature: 10 ºC to 45 ºC, Pressure : 50 kPa to 500 kPa, Volume flow rate: 2 L/min to 700 L/min, Mass flow rate: 2 kg/min to 700 kg/min, Accumulated volume: 0.02 m 3 to 0.6 m 3, Accumulated mass: 20 kg to 600 kg, Velocity: 0.1 m/s to 10 m/s. reservoir capacity : 3.2 m 3. System relative expanded uncertainty: Mass and volume: 0.03 %, Mass flow rate and volume flow rate: 0.04 %, Velocity: 1.00 %. 5

Copyright 2009 ITRI 工業技術研究院 Calibration of the CMS 6 Pressure regulator for pressure control and stabilization High pressure water pump Soft pad to isolate vibration (critical for zero setting) Small-diameter high-pressure hose and valve to avoid bubble generation in the downstream

Copyright 2009 ITRI 工業技術研究院 NMIA LPG flow system Two 6000 L tanks, Propane & Butane Two pumps, giving flow rates of up to 1700 L/min At 20 ºC, 800 kPa (propane), 300 kPa (butane) Reference standard: 40 L piston prover Omni 6000 electronic controller Base uncertainty 0.03 % 7

Copyright 2009 ITRI 工業技術研究院 Calibration of the NMIA 12 bars 9 bars Flow rate: 10 kg/min 、 20 kg/min 、 30 kg/min 、 40 kg/min 、 50 kg/min 8

Copyright 2009 ITRI 工業技術研究院 Calibration of the NMIA 9

Copyright 2009 ITRI 工業技術研究院 Test Results of Water Flow Under the same upstream pressure, the deviation in meter factor (MF) is less than 0.04 % Deviation in MF less than 0.04 % between test results of upstream pressure 9 bars and 0.3 bar Deviation in MF less than 0.05 % between test results of upstream pressure 12 bars and 0.3 bar Pressure effect on the meter performance can be observed 10

Copyright 2009 ITRI 工業技術研究院 Test Results of LPG (Propane & Butane) Flows Propane: zero 12 bars, tested with volume flow 12 bars Butane: zero 12 bars, tested with volume flow 9 bars Deviation in MF between the two fluids is less than 0.06 % 11

Copyright 2009 ITRI 工業技術研究院 Check for Density Measurement Performance of the TS 12 Test fluid: Exxsol DSP 80 (chemical solvent, Hydrocarbons) Tested under normal pressure The maximum deviation less than g/cm 3

Copyright 2009 ITRI 工業技術研究院 Summary Progress –Flow measurement performance of the TS with various working fluids CMS; propane and NMIA) under pressures of 0.3 bar, 9 bars and 12 bars tested Overall speaking, the meter performance is very good Pressure effect on the meter performance observed in water flow system but not significant in LPG system Additional lessons learnt for meter calibration at elevated pressure using gravimetric water flow system –Pressure regulator to improve pressure stability –Small-dia. high-Pressure hose and valve to avoid bubble formation in the downstream –Density measurement performance of the TS tested Future Work –Re-calibrate the CMS to check for meter stability –Re-calibrate the CMS at downstream pressures of 12 bars and 9 bars (same as the condition at NMIA) –Re-test the CMS with volume flow (pulses per liter) signal output –Analyze the data obtained by CMS and NMIA and see if varying working fluid impacts the meter performance –Test the density measurement performance of the TS at high-pressure –NMIA will continue to work on establishing a method for LPG density measurement at different temperatures 13

Copyright 2009 ITRI 工業技術研究院 The Hard-workers 14 Simon Dignan (NMIA) Kun-Chih Tsai (CMS) Subra (NMIA)

Copyright 2009 ITRI 工業技術研究院 15 Thanks for your attention! Questions?

Copyright 2009 ITRI 工業技術研究院 16 Concept of Verifying LPG Fuel Dispensers by Coriolis Mass Flow Meter LPG Fuel Dispensers V FD Master Meter (Coriolis Meter) M mm,  (T mm,P mm ), T mm, P mm NIST REFPROP 8.0:  (T mm,P mm ) x C3H8, x C4H10 (molar fraction) Thermometer + Pressure Gauge T FD, P FD  (T FD,P FD ) NIST REFPROP 8.0: x C3H8, x C4H10, T FD,P FD  (T FD,P FD ), or  (15,P FD ), V FD : Volume indicated by fuel dispenser in temperature uncompensated mode V FD,C : V FD converted to base conditions

Copyright 2009 ITRI 工業技術研究院 Test NMIA 17