The Experts below are selected from a list of 330 Experts worldwide ranked by ideXlab platform
Tokihiko Kobata - One of the best experts on this subject based on the ideXlab platform.
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final report on key comparison ccm p k7 in the range 10 mpa to 100 mpa of hydraulic Gauge Pressure
Metrologia, 2005Co-Authors: Wladimir Sabuga, Sanjay Yadav, Douglas A Olson, J C Torres, Y Jin, Tokihiko Kobata, P OtalAbstract:This report describes a CCM key comparison of hydraulic Pressure standards of nine National Metrology Institutes that was carried out in the period from November 2002 to June 2004 in order to determine their degrees of equivalence in the range 10 MPa to 100 MPa of the Gauge Pressure. The pilot laboratory was PTB. The primary Pressure standards were Pressure balances of different design equipped with piston-cylinder assemblies operated in freedeformation, controlled-clearance or re-entrant operation mode. The transfer standard was a Pressure balance equipped with a piston-cylinder assembly and a mass set. The Pressuredependent effective areas of the transfer standard at specified Pressures were reported by the participants and led to the reference values calculated as medians. All participants’ results agree with the reference values and with each other within the expanded uncertainties calculated with a coverage factor 2, most of them even within their standard uncertainties. In addition, the results were analysed in terms of the zero Pressure effective area and the Pressure distortion coefficient. Also for them agreement within expanded uncertainties (k=2) is observed. The results of the comparison demonstrate equivalence of the laboratory standards and support their measurement capability statements.
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final report on key comparison apmp m p k13 in hydraulic Gauge Pressure from 50 mpa to 500 mpa
Metrologia, 2005Co-Authors: Hiroaki Kajikawa, Sanjay Yadav, Tokihiko Kobata, Wu Jian, Tawat Changpan, Neville Owen, Li Yanhua, Chenchuan Hung, Gigin Ginanjar, Inmook ChoiAbstract:This report describes the results of a key comparison of hydraulic high-Pressure standards at 16 national metrology institutes (NMIs: NMIJ/AIST, NPLI, CSIR-NML, NIS, KRISS, SCL, SPRING, NMIA, VMI, NML-SIRIM, KIM-LIPI, NSCL, PTB, NIMT, CMS/ITRI and NIM) was carried out during the period October 2002 to July 2004 within the framework of the Asia-Pacific Metrology Programme (APMP) in order to determine their degrees of equivalence at Pressures in the range 10 MPa to 100 MPa for Gauge mode. The pilot institute was the National Metrology Institute of Japan (NMIJ)/AIST. All participating institutes generally used hydraulic Pressure balances as their Pressure standards. High-precision Pressure transducers were used as transfer standards. The sensing element of the transducer was a precision quartz crystal resonator. To ensure the reliability of the transfer standard, two Pressure transducers were used on a transfer standard unit. Three nominally identical transfer packages were circulated independently to reduce the time required for the measurements. During this comparison, the three transfer standards were calibrated simultaneously at the pilot institute 11 times in total. From the calibration results, the behaviours of the transfer standards during the comparison period were well characterized and it was presented that the capabilities of the transfer standards to achieve this key comparison were sufficient. The degrees of equivalence of each national measurement standard were expressed quantitatively by two terms, deviations from the key comparison reference values and pair-wise differences of their deviations. The degrees of equivalence in this comparison were also transferred to the corresponding CCM key comparison, CCM.M.P-K7. The hydraulic Pressure standards in the range 10 MPa to 100 MPa for Gauge mode of the 16 participating NMIs were found to be equivalent within their claimed uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the Mutual Recognition Arrangement (MRA).
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final report on key comparison apmp m p k7 in hydraulic Gauge Pressure from 10 mpa to 100 mpa
Metrologia, 2005Co-Authors: Tokihiko Kobata, Wu Jian, A K Bandyopadhyay, Ken Moore, Alaaeldin A E Eltawil, Tak Kin Chan, Chen Soo Fatt, Wenda Permana, Mohamad Aldammad, Wladimir SabugaAbstract:This report describes the results of a key comparison of hydraulic high-Pressure standards at 16 national metrology institutes (NMIs: NMIJ/AIST, NPLI, CSIR-NML, NIS, KRISS, SCL, SPRING, NMIA, VMI, NML-SIRIM, KIM-LIPI, NSCL, PTB, NIMT, CMS/ITRI and NIM) was carried out during the period October 2002 to July 2004 within the framework of the Asia-Pacific Metrology Programme (APMP) in order to determine their degrees of equivalence at Pressures in the range 10 MPa to 100 MPa for Gauge mode. The pilot institute was the National Metrology Institute of Japan (NMIJ)/AIST. All participating institutes generally used hydraulic Pressure balances as their Pressure standards. High-precision Pressure transducers were used as transfer standards. The sensing element of the transducer was a precision quartz crystal resonator. To ensure the reliability of the transfer standard, two Pressure transducers were used on a transfer standard unit. Three nominally identical transfer packages were circulated independently to reduce the time required for the measurements. During this comparison, the three transfer standards were calibrated simultaneously at the pilot institute 11 times in total. From the calibration results, the behaviours of the transfer standards during the comparison period were well characterized and it was presented that the capabilities of the transfer standards to achieve this key comparison were sufficient. The degrees of equivalence of each national measurement standard were expressed quantitatively by two terms, deviations from the key comparison reference values and pair-wise differences of their deviations. The degrees of equivalence in this comparison were also transferred to the corresponding CCM key comparison, CCM.M.P-K7. The hydraulic Pressure standards in the range 10 MPa to 100 MPa for Gauge mode of the 16 participating NMIs were found to be equivalent within their claimed uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the Mutual Recognition Arrangement (MRA).
Wladimir Sabuga - One of the best experts on this subject based on the ideXlab platform.
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final report on key comparison ccm p k7 in the range 10 mpa to 100 mpa of hydraulic Gauge Pressure
Metrologia, 2005Co-Authors: Wladimir Sabuga, Sanjay Yadav, Douglas A Olson, J C Torres, Y Jin, Tokihiko Kobata, P OtalAbstract:This report describes a CCM key comparison of hydraulic Pressure standards of nine National Metrology Institutes that was carried out in the period from November 2002 to June 2004 in order to determine their degrees of equivalence in the range 10 MPa to 100 MPa of the Gauge Pressure. The pilot laboratory was PTB. The primary Pressure standards were Pressure balances of different design equipped with piston-cylinder assemblies operated in freedeformation, controlled-clearance or re-entrant operation mode. The transfer standard was a Pressure balance equipped with a piston-cylinder assembly and a mass set. The Pressuredependent effective areas of the transfer standard at specified Pressures were reported by the participants and led to the reference values calculated as medians. All participants’ results agree with the reference values and with each other within the expanded uncertainties calculated with a coverage factor 2, most of them even within their standard uncertainties. In addition, the results were analysed in terms of the zero Pressure effective area and the Pressure distortion coefficient. Also for them agreement within expanded uncertainties (k=2) is observed. The results of the comparison demonstrate equivalence of the laboratory standards and support their measurement capability statements.
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final report on key comparison apmp m p k7 in hydraulic Gauge Pressure from 10 mpa to 100 mpa
Metrologia, 2005Co-Authors: Tokihiko Kobata, Wu Jian, A K Bandyopadhyay, Ken Moore, Alaaeldin A E Eltawil, Tak Kin Chan, Chen Soo Fatt, Wenda Permana, Mohamad Aldammad, Wladimir SabugaAbstract:This report describes the results of a key comparison of hydraulic high-Pressure standards at 16 national metrology institutes (NMIs: NMIJ/AIST, NPLI, CSIR-NML, NIS, KRISS, SCL, SPRING, NMIA, VMI, NML-SIRIM, KIM-LIPI, NSCL, PTB, NIMT, CMS/ITRI and NIM) was carried out during the period October 2002 to July 2004 within the framework of the Asia-Pacific Metrology Programme (APMP) in order to determine their degrees of equivalence at Pressures in the range 10 MPa to 100 MPa for Gauge mode. The pilot institute was the National Metrology Institute of Japan (NMIJ)/AIST. All participating institutes generally used hydraulic Pressure balances as their Pressure standards. High-precision Pressure transducers were used as transfer standards. The sensing element of the transducer was a precision quartz crystal resonator. To ensure the reliability of the transfer standard, two Pressure transducers were used on a transfer standard unit. Three nominally identical transfer packages were circulated independently to reduce the time required for the measurements. During this comparison, the three transfer standards were calibrated simultaneously at the pilot institute 11 times in total. From the calibration results, the behaviours of the transfer standards during the comparison period were well characterized and it was presented that the capabilities of the transfer standards to achieve this key comparison were sufficient. The degrees of equivalence of each national measurement standard were expressed quantitatively by two terms, deviations from the key comparison reference values and pair-wise differences of their deviations. The degrees of equivalence in this comparison were also transferred to the corresponding CCM key comparison, CCM.M.P-K7. The hydraulic Pressure standards in the range 10 MPa to 100 MPa for Gauge mode of the 16 participating NMIs were found to be equivalent within their claimed uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the Mutual Recognition Arrangement (MRA).
Sanjay Yadav - One of the best experts on this subject based on the ideXlab platform.
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development of strain Gauge Pressure transducer up to 2000 bar
2010Co-Authors: Kuma Anuj, Ravinde Agarwal, Sanjay YadavAbstract:A number of Pressure transducers, based on strain Gauge, capacitance / inductance type, frequency resonators, are commercially available and are being used for sensing and producing an electrical output proportional to applied Pressure. These sensors have their own advantages and limitations due to operational ease, linearity, hysteresis error, measurement uncertainty and the costs. Strain Gauge type transducers are now well established devices for accurate and precise measurement of Pressure within measurement uncertainty up to 0.1 % of full scale. In the present thesis work, an indigenous strain Gauge Pressure transducer has been designed, developed, tested and calibrated for Pressure measurement up to 200 MPa or 2000 bar. The measurement uncertainty estimated using the Pressure transducer is found better than 0.1 % of full scale. This transducer is developed using four foil type strain gages, bonded two in axial direction while other two in radial direction, to the controlled stress zones of a tubular maraging steel active cylinder working also as diaphragm. The strain gages are then connected to a Wheatstone bridge arrangement to measure stress generated strains. The Pressure is applied through matching connector designed in the same tubular transducer active element. The treaded unique design in a single piece through collar, ferule and tubing arrangement provides leak proof Pressure connections with external devices without using additional seals. The calibration and performance checking of the Pressure transducer is carried out using dead weight type national Pressure standard using the internationally accepted calibration procedure.
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investigations on measurement uncertainty and stability of Pressure dial Gauges and transducers
Measurement Science Review, 2010Co-Authors: Sanjay Yadav, V K Gupta, A K BandyopadhyayAbstract:Several commercial instruments are available for Pressure measurements. As per ISO stipulations, whenever such instruments are used for precise and accurate Pressure measurements, it is obligatory on the part of measurement authority to indicate the quality of results. Stability of the Pressure measuring instruments over the years is one of the important parameters in defining the quality of results quantitatively. Also, it helps the users to decide the optimum calibration interval of the particular instrument. In the present investigation, we have studied a number of analogue / digital Pressure transducers / transmitters / calibrators and Pressure dial Gauges. The present paper describes the results of the studies carried out on several Pressure dial Gauges and transducers in the Pressure range up to 500 MPa, calibrated several times over the years, as examples. A new approach is proposed for the establishment of measurement uncertainty for such instruments by characterizing the data obtained during calibration over the years using curve fitting. Keywords: Pressure metrology, Pressure dial Gauge, Pressure transducer, calibration, measurement uncertainty, stability
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final report on key comparison ccm p k7 in the range 10 mpa to 100 mpa of hydraulic Gauge Pressure
Metrologia, 2005Co-Authors: Wladimir Sabuga, Sanjay Yadav, Douglas A Olson, J C Torres, Y Jin, Tokihiko Kobata, P OtalAbstract:This report describes a CCM key comparison of hydraulic Pressure standards of nine National Metrology Institutes that was carried out in the period from November 2002 to June 2004 in order to determine their degrees of equivalence in the range 10 MPa to 100 MPa of the Gauge Pressure. The pilot laboratory was PTB. The primary Pressure standards were Pressure balances of different design equipped with piston-cylinder assemblies operated in freedeformation, controlled-clearance or re-entrant operation mode. The transfer standard was a Pressure balance equipped with a piston-cylinder assembly and a mass set. The Pressuredependent effective areas of the transfer standard at specified Pressures were reported by the participants and led to the reference values calculated as medians. All participants’ results agree with the reference values and with each other within the expanded uncertainties calculated with a coverage factor 2, most of them even within their standard uncertainties. In addition, the results were analysed in terms of the zero Pressure effective area and the Pressure distortion coefficient. Also for them agreement within expanded uncertainties (k=2) is observed. The results of the comparison demonstrate equivalence of the laboratory standards and support their measurement capability statements.
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final report on key comparison apmp m p k13 in hydraulic Gauge Pressure from 50 mpa to 500 mpa
Metrologia, 2005Co-Authors: Hiroaki Kajikawa, Sanjay Yadav, Tokihiko Kobata, Wu Jian, Tawat Changpan, Neville Owen, Li Yanhua, Chenchuan Hung, Gigin Ginanjar, Inmook ChoiAbstract:This report describes the results of a key comparison of hydraulic high-Pressure standards at 16 national metrology institutes (NMIs: NMIJ/AIST, NPLI, CSIR-NML, NIS, KRISS, SCL, SPRING, NMIA, VMI, NML-SIRIM, KIM-LIPI, NSCL, PTB, NIMT, CMS/ITRI and NIM) was carried out during the period October 2002 to July 2004 within the framework of the Asia-Pacific Metrology Programme (APMP) in order to determine their degrees of equivalence at Pressures in the range 10 MPa to 100 MPa for Gauge mode. The pilot institute was the National Metrology Institute of Japan (NMIJ)/AIST. All participating institutes generally used hydraulic Pressure balances as their Pressure standards. High-precision Pressure transducers were used as transfer standards. The sensing element of the transducer was a precision quartz crystal resonator. To ensure the reliability of the transfer standard, two Pressure transducers were used on a transfer standard unit. Three nominally identical transfer packages were circulated independently to reduce the time required for the measurements. During this comparison, the three transfer standards were calibrated simultaneously at the pilot institute 11 times in total. From the calibration results, the behaviours of the transfer standards during the comparison period were well characterized and it was presented that the capabilities of the transfer standards to achieve this key comparison were sufficient. The degrees of equivalence of each national measurement standard were expressed quantitatively by two terms, deviations from the key comparison reference values and pair-wise differences of their deviations. The degrees of equivalence in this comparison were also transferred to the corresponding CCM key comparison, CCM.M.P-K7. The hydraulic Pressure standards in the range 10 MPa to 100 MPa for Gauge mode of the 16 participating NMIs were found to be equivalent within their claimed uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the Mutual Recognition Arrangement (MRA).
Stephen Gray - One of the best experts on this subject based on the ideXlab platform.
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effect of applied Pressure on performance of ptfe membrane in dcmd
Journal of Membrane Science, 2011Co-Authors: Jianhua Zhang, Junde Li, Stephen GrayAbstract:In membrane distillation (MD), mass and heat transfer occurs simultaneously through the membrane. According to the theory for mass and heat balance, if the membrane is compressible, total Pressure in the pore and the thermal resistance of the membrane will change and affect the performance of the membrane. To verify this theory, direct contact membrane distillation (DCMD) experiments were conducted in which the absolute Pressures applied on both sides of membranes were controlled identically and varied independently of the flowrates. Both hollow fibre and flat-sheet membrane modules were employed. The hollow fibre membrane had a rigid structure that was not deformable over the range of experimental Pressures (1–50 kPa), while the composite flat-sheet membrane was composed of a scrim support layer and a sponge-like PTFE active layer that was compressible over the range of Pressures considered. When Pressures were applied on both sides of the compressible membrane, the volume of active layer will become smaller. As the active layer was compressed in the tested Pressure range, the void volume (porosity) and the thickness of the active layer was reduced, which resulted in the reduction of the thermal resistance of the membrane and so increased the heat conduction loss across the membrane. Furthermore, if there is no air escaping out of the membrane pores, the air Pressure within the pores will increase due to the reduction of void volume (porosity), leading to an increase of the mass transfer resistance. The effect of Pressure on the flux was also considered at different velocities (0.095 and 0.114 m/s) and temperatures (50 and 70 °C). For the composite flat-sheet membrane, there was a 15–39% flux reduction when the Gauge Pressure was increased from 1 to 45 kPa at constant inlet temperatures and flowrates. However, there was no noticeable change of flux with Pressure for the incompressible hollow fibre module.
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effect of applied Pressure on performance of ptfe membrane in dcmd
Journal of Membrane Science, 2011Co-Authors: Jianhua Zhang, Junde Li, Stephen GrayAbstract:In membrane distillation (MD), mass and heat transfer occurs simultaneously through the membrane. According to the theory for mass and heat balance, if the membrane is compressible, total Pressure in the pore and the thermal resistance of the membrane will change and affect the performance of the membrane. To verify this theory, direct contact membrane distillation (DCMD) experiments were conducted in which the absolute Pressures applied on both sides of membranes were controlled identically and varied independently of the flowrates. Both hollow fibre and flat-sheet membrane modules were employed. The hollow fibre membrane had a rigid structure that was not deformable over the range of experimental Pressures (1–50 kPa), while the composite flat-sheet membrane was composed of a scrim support layer and a sponge-like PTFE active layer that was compressible over the range of Pressures considered. When Pressures were applied on both sides of the compressible membrane, the volume of active layer will become smaller. As the active layer was compressed in the tested Pressure range, the void volume (porosity) and the thickness of the active layer was reduced, which resulted in the reduction of the thermal resistance of the membrane and so increased the heat conduction loss across the membrane. Furthermore, if there is no air escaping out of the membrane pores, the air Pressure within the pores will increase due to the reduction of void volume (porosity), leading to an increase of the mass transfer resistance. The effect of Pressure on the flux was also considered at different velocities (0.095 and 0.114 m/s) and temperatures (50 and 70 °C). For the composite flat-sheet membrane, there was a 15–39% flux reduction when the Gauge Pressure was increased from 1 to 45 kPa at constant inlet temperatures and flowrates. However, there was no noticeable change of flux with Pressure for the incompressible hollow fibre module.
Wu Jian - One of the best experts on this subject based on the ideXlab platform.
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final report on key comparison apmp m p k13 in hydraulic Gauge Pressure from 50 mpa to 500 mpa
Metrologia, 2005Co-Authors: Hiroaki Kajikawa, Sanjay Yadav, Tokihiko Kobata, Wu Jian, Tawat Changpan, Neville Owen, Li Yanhua, Chenchuan Hung, Gigin Ginanjar, Inmook ChoiAbstract:This report describes the results of a key comparison of hydraulic high-Pressure standards at 16 national metrology institutes (NMIs: NMIJ/AIST, NPLI, CSIR-NML, NIS, KRISS, SCL, SPRING, NMIA, VMI, NML-SIRIM, KIM-LIPI, NSCL, PTB, NIMT, CMS/ITRI and NIM) was carried out during the period October 2002 to July 2004 within the framework of the Asia-Pacific Metrology Programme (APMP) in order to determine their degrees of equivalence at Pressures in the range 10 MPa to 100 MPa for Gauge mode. The pilot institute was the National Metrology Institute of Japan (NMIJ)/AIST. All participating institutes generally used hydraulic Pressure balances as their Pressure standards. High-precision Pressure transducers were used as transfer standards. The sensing element of the transducer was a precision quartz crystal resonator. To ensure the reliability of the transfer standard, two Pressure transducers were used on a transfer standard unit. Three nominally identical transfer packages were circulated independently to reduce the time required for the measurements. During this comparison, the three transfer standards were calibrated simultaneously at the pilot institute 11 times in total. From the calibration results, the behaviours of the transfer standards during the comparison period were well characterized and it was presented that the capabilities of the transfer standards to achieve this key comparison were sufficient. The degrees of equivalence of each national measurement standard were expressed quantitatively by two terms, deviations from the key comparison reference values and pair-wise differences of their deviations. The degrees of equivalence in this comparison were also transferred to the corresponding CCM key comparison, CCM.M.P-K7. The hydraulic Pressure standards in the range 10 MPa to 100 MPa for Gauge mode of the 16 participating NMIs were found to be equivalent within their claimed uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the Mutual Recognition Arrangement (MRA).
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final report on key comparison apmp m p k7 in hydraulic Gauge Pressure from 10 mpa to 100 mpa
Metrologia, 2005Co-Authors: Tokihiko Kobata, Wu Jian, A K Bandyopadhyay, Ken Moore, Alaaeldin A E Eltawil, Tak Kin Chan, Chen Soo Fatt, Wenda Permana, Mohamad Aldammad, Wladimir SabugaAbstract:This report describes the results of a key comparison of hydraulic high-Pressure standards at 16 national metrology institutes (NMIs: NMIJ/AIST, NPLI, CSIR-NML, NIS, KRISS, SCL, SPRING, NMIA, VMI, NML-SIRIM, KIM-LIPI, NSCL, PTB, NIMT, CMS/ITRI and NIM) was carried out during the period October 2002 to July 2004 within the framework of the Asia-Pacific Metrology Programme (APMP) in order to determine their degrees of equivalence at Pressures in the range 10 MPa to 100 MPa for Gauge mode. The pilot institute was the National Metrology Institute of Japan (NMIJ)/AIST. All participating institutes generally used hydraulic Pressure balances as their Pressure standards. High-precision Pressure transducers were used as transfer standards. The sensing element of the transducer was a precision quartz crystal resonator. To ensure the reliability of the transfer standard, two Pressure transducers were used on a transfer standard unit. Three nominally identical transfer packages were circulated independently to reduce the time required for the measurements. During this comparison, the three transfer standards were calibrated simultaneously at the pilot institute 11 times in total. From the calibration results, the behaviours of the transfer standards during the comparison period were well characterized and it was presented that the capabilities of the transfer standards to achieve this key comparison were sufficient. The degrees of equivalence of each national measurement standard were expressed quantitatively by two terms, deviations from the key comparison reference values and pair-wise differences of their deviations. The degrees of equivalence in this comparison were also transferred to the corresponding CCM key comparison, CCM.M.P-K7. The hydraulic Pressure standards in the range 10 MPa to 100 MPa for Gauge mode of the 16 participating NMIs were found to be equivalent within their claimed uncertainties. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the Mutual Recognition Arrangement (MRA).