20.500.12556/RUL-146672 Investigation of the discharge coefficient in the laminar boundary layer regime of critical flow Venturi nozzles calibrated with different gases including hydrogen This study represents the first step towards the introduction of critical flow Venturi nozzles into the traceability scheme for gaseous hydrogen and addresses the characterisation of the hydrogen discharge coefficient in the laminar boundary layer regime and the identification of a potential alternative gas for nozzle calibration. The experimental study presented was performed for two nozzles with a throat diameter of 0.175 mm and 0.436 mm. The tests were performed with six different gases, including hydrogen, covering a Reynolds number range from 1.5⋅10$^3$ to 6⋅10$^4$. The experimental results show that the discharge coefficient depends not only on the Reynolds number but also on the isentropic exponent of the gas. Based on the experimental data, theoretical models taking into account the isentropic exponent and the Prandtl number of the gas were evaluated. The study indicates possibilities to use inert gases instead of hydrogen in calibration processes. critical flow Venturi nozzle discharge coefficient experimental analysis hydrogen flow kritične Venturijeve merilne šobe pretočni koeficient eksperimentalne analize pretok vodika true false true Angleški jezik Slovenski jezik Članek v reviji 2023-06-06 07:47:30 2023-06-06 07:47:32 2024-03-11 12:47:02 0000-00-00 00:00:00 2023 0 0 7 str. Vol. 217, art. 113134 Aug. 2023 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 532:681.122 1873-412X 10.1016/j.measurement.2023.113134 154551299 Bobovnik_..._-Investigation_of_the_discharge_coefficient_in_the_laminar_boundary_layer_regime_of_critical_flow_Venturi_nozzles_calibrated_with_different_gases_including_hydrogen.pdf Bobovnik_..._-Investigation_of_the_discharge_coefficient_in_the_laminar_boundary_layer_regime_of_critical_flow_Venturi_nozzles_calibrated_with_different_gases_including_hydrogen.pdf 1 0C37ECF00685C9D7DBD186DFF9DD480D 893aca1ddfe2d8b9fc48cfd32c7e00e0be2866f23602a144dee3998e3dc8ffd5 cce9bdec-042f-11ee-a314-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=169909 https://www.sciencedirect.com/science/article/pii/S026322412300698X 1 4f2f7740-042d-11ee-a314-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=169908 Fakulteta za strojništvo 0 0 0