Thermal mass flow meter CALIBRATION concluding Joao MarquesTheodoros

Thermal mass flow meter CALIBRATION concluding. . . Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Coriolis vs Thermal Mass 1) Trying to indentify if there's any temperature influence on the measurements in a range of -40 C<T<10 C to the flow of the two flow meters connected in line and only after adjust the K-value and see if we can match flow readout with the coriolis meter. 2) At Flows of 2. 5 g/s, 7. 5 g/s, 10 g/s, 12. 5 g/s. 3) When the liquid Temperature reaches the lowest value, the compressor is switched off (the pump is still working as we have plenty of sub cooling), trying to warm up the liquid gas CO 2 and to indentify if any increase of Temperature really changes thermal mass flow meter’s behavior. 4) Trying to find both flow meters deviation and then to calibrate them by re-adjusting the K value. 5) Calibration Theodoros Katopodis_PH/CMX 12/5/2020 2

Coriolis vs Thermal Mass 0, 57% Total Measuring Accuracy = 0. 57% (of actual measured flow rate) 0. 1% + Zero stability (of maximum flow rate) = 0. 0057%+0. 0056%x 60⁰C+0. 013 x 10 bar Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Coriolis vs Thermal Mass Flow Meter Coriolis Flow Meter Not a significant flow difference (around 0, 5 g/s) during the Temperature increase, not actually matter of Temperature influence. Temperature Compressor switches off/on Theodoros Katopodis_PH/CMX 12/5/2020 4

Coriolis vs Thermal Mass y=x Theodoros Katopodis_PH/CMX 12/5/2020 5

Coriolis vs Thermal Mass It’s Calibration time… Accuracy: 0. 5% of Full Scale or 2% of reading over the calibrated range. K-Value or offset can be adjusted by using the Span Pot R 11 located on the logic board. This is a 22 Turn Pot clockwise to increase reading, counter clockwise to decrease. Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration Coriolis Flow Meter 19. 09. 2012 Testing region Scanning the whole pump range of flows form 16. 5 g/s to 2 g/s (with a step of 2 -2. 5 g/s). Similar results on both ways measurements. A B C A, C : Tuning Region Just to remind that calibration was done by fitting flows at the largest set point of 16, 5 g/s. Focusing on the two current flows and tuning again: 1) 10 g/s 2) 7. 5 g/s Thermal Mass Flow Meter Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration 19. 09. 2012 1 2 B 3 Tested area 4 5 6 1. 2. 3. 4. 5. 6. 7. Coriolis Coriolis m=16. 6 g/s/Thermal m=16. 3 g/s m=14 g/s/ Thermal m=13, 75 g/s m=12, 1 g/s/ Thermal m=12, 2 g/s m=9, 25 g/s/ Thermal m=9. 42 g/s m=7, 25 g/s/ Thermal m=7, 75 g/s m=4, 92 g/s/ Thermal m=5, 32 g/s m=2, 38 g/s/ Thermal m=2, 03 g/s 7 offset offset of of 0. 3 0. 25 0. 0 0. 23 0. 5 0. 04 0. 28 Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration 20. 09. 2012 A A and B are the tuning regions, focusing on these three current flows and tuning again: 1) 10 g/s 2) 7. 5 g/s 3) 5 g/s B These spikes are due to the accumulator’s CO 2 filling, the alarm was triggered as the temperature went up! Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration Flow range 16, 5 -g/s to 2, 5 g/s 0, 6 g/s 0, 4 g/s It can be tuned really accurate only for a flow range of 5 g/s. Focusing on the flow range between 10 and 5 g/s. 14 g/s 0, 35 g/s 11, 5 g/s 0, 01 g/s 0, 2 g/s In the full testing area, the really lower offset is achieved at this chosen flow region with a given level of accuracy @0, 2 g/s. 9, 5 g/s 0, 25 g/s 0, 5 g/s 20. 09. 2012 16, 5 g/s 2, 5 g/s 7, 5 g/s Before and after the chosen flow range the offset is big enough. Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration Already improved results. 20. 09. 2012 The whole tested area Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration Even more accurate measurements on the focused area, with a smaller offset of 0. 2 g/s 20. 09. 2012 Targeted area 10 g/s-2, 5 g/s Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration 21. 09. 2012 In terms of accuracy it can’t be better. After several efforts, we achieved the maximum efficiency (? ) of this thermal mass flow meter. 9, 5 g/s 7, 5 g/s We managed to calibrate it so well as to have a lower offset of 0, 2 g/s for flows between 2 g/s to 9, 5 g/s 2, 5 g/s Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration Even more improved results. 20. 09. 2012 The whole tested area Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Thermal Mass Flow Meter Calibration Even more accurated measurements on the focused area, with a smaller offset of 0. 2 g/s 21. 09. 2012 Targeted area 10 g/s-2, 5 g/s Joao Marques/Theodoros Katopodis_PH/CMX 12/5/2020

Coriolis vs Thermal Mass Conclusions After a good round of testing with really acceptable measurements we can conclude that : i) There's no any temperature influence on the measurements at all. ii) In terms of accuracy it can’t be better. iii) Let's say that it can be tuned only for a flow range around 7, 5 g/s. So it can be adjusted pretty well on the flow region between 2, 5 and 10 g/s. iv) Maybe we could try to order one with a smaller range, not up to 24 g/s. Theodoros Katopodis_PH/CMX 12/5/2020 16