Leakage Flow Influence on SHF pump model performances

Dupont, Patrick,Bayeul-Laine, Annie-Claude,Dazin, Antoine,Bois, Gerard,Roussette, Olivier,Si, Qiaorui Korean Society for Fluid machinery 2015 International journal of fluid machinery and syste Vol.8 No.3

This paper deals with the influence of leakage flow existing in SHF pump model on the analysis of internal flow behaviour inside the vane diffuser of the pump model performance using both experiments and calculations. PIV measurements have been performed at different hub to shroud planes inside one diffuser channel passage for a given speed of rotation and various flow rates. For each operating condition, the PIV measurements have been trigged with different angular impeller positions. The performances and the static pressure rise of the diffuser were also measured using a three-hole probe. The numerical simulations were carried out with Star CCM+ 9.06 code (RANS frozen and unsteady calculations). Some results were already presented at the XXth IAHR Symposium for three flowrates for RANS frozen and URANS calculations. In the present paper, comparisons between URANS calculations with and without leakages and experimental results are presented and discussed for these flow rates. The performances of the diffuser obtained by numerical calculations are compared to those obtained by the three-holes probe measurements. The comparisons show the influence of fluid leakages on global performances and a real improvement concerning the efficiency of the diffuser, the pump and the velocity distributions. These results show that leakage is an important parameter that has to be taken into account in order to make improved comparisons between numerical approaches and experiments in such a specific model set up.

Leakage Flow Influence on SHF pump model performances

Dupont, Patrick,Bayeul-Laine, Annie-Claude,Dazin, Antoine,Bois, Gerard,Roussette, Olivier,Si, Qiaorui Korean Society for Fluid machinery 2015 International journal of fluid machinery and syste Vol.8 No.4

This paper deals with the influence of leakage flow existing in SHF pump model on the analysis of internal flow behaviour inside the vane diffuser of the pump model performance using both experiments and calculations. PIV measurements have been performed at different hub to shroud planes inside one diffuser channel passage for a given speed of rotation and various flow rates. For each operating condition, the PIV measurements have been trigged with different angular impeller positions. The performances and the static pressure rise of the diffuser were also measured using a three-hole probe. The numerical simulations were carried out with Star CCM+ 9.06 code (RANS frozen and unsteady calculations). Some results were already presented at the XXth IAHR Symposium for three flowrates for RANS frozen and URANS calculations. In the present paper, comparisons between URANS calculations with and without leakages and experimental results are presented and discussed for these flow rates. The performances of the diffuser obtained by numerical calculations are compared to those obtained by the three-holes probe measurements. The comparisons show the influence of fluid leakages on global performances and a real improvement concerning the efficiency of the diffuser, the pump and the velocity distributions. These results show that leakage is an important parameter that has to be taken into account in order to make improved comparisons between numerical approaches and experiments in such a specific model set up.

Leakage Flow Influence on SHF pump model performances

Annie-Claude Bayeul-Lainé,Patrick Dupont,Antoine Dazin,Gérard Bois,Olivier Roussette,Qiaorui Si 한국유체기계학회 2015 International journal of fluid machinery and syste Vol.8 No.4

This paper deals with the influence of leakage flow existing in SHF pump model on the analysis of internal flow behaviour inside the vane diffuser of the pump model performance using both experiments and calculations. PIV measurements have been performed at different hub to shroud planes inside one diffuser channel passage for a given speed of rotation and various flow rates. For each operating condition, the PIV measurements have been trigged with different angular impeller positions. The performances and the static pressure rise of the diffuser were also measured using a three-hole probe. The numerical simulations were carried out with Star CCM+ 9.06 code (RANS frozen and unsteady calculations). Some results were already presented at the XXth IAHR Symposium for three flowrates for RANS frozen and URANS calculations. In the present paper, comparisons between URANS calculations with and without leakages and experimental results are presented and discussed for these flow rates. The performances of the diffuser obtained by numerical calculations are compared to those obtained by the three-holes probe measurements. The comparisons show the influence of fluid leakages on global performances and a real improvement concerning the efficiency of the diffuser, the pump and the velocity distributions. These results show that leakage is an important parameter that has to be taken into account in order to make improved comparisons between numerical approaches and experiments in such a specific model set up.

Leakage Flow Influence on SHF pump model performances

Patrick Dupont,Annie-Claude Bayeul-Lainé,Antoine Dazin,Gérard Bois,Olivier Roussette,Qiaorui Si 한국유체기계학회 2015 International journal of fluid machinery and syste Vol.8 No.3

This paper deals with the influence of leakage flow existing in SHF pump model on the analysis of internal flow behaviour inside the vane diffuser of the pump model performance using both experiments and calculations. PIV measurements have been performed at different hub to shroud planes inside one diffuser channel passage for a given speed of rotation and various flow rates. For each operating condition, the PIV measurements have been trigged with different angular impeller positions. The performances and the static pressure rise of the diffuser were also measured using a three-hole probe. The numerical simulations were carried out with Star CCM+ 9.06 code (RANS frozen and unsteady calculations). Some results were already presented at the XXth IAHR Symposium for three flowrates for RANS frozen and URANS calculations. In the present paper, comparisons between URANS calculations with and without leakages and experimental results are presented and discussed for these flow rates. The performances of the diffuser obtained by numerical calculations are compared to those obtained by the three-holes probe measurements. The comparisons show the influence of fluid leakages on global performances and a real improvement concerning the efficiency of the diffuser, the pump and the velocity distributions. These results show that leakage is an important parameter that has to be taken into account in order to make improved comparisons between numerical approaches and experiments in such a specific model set up.

Static pressure recovery analysis in the vane island diffuser of a centrifugal pump

Qiaorui Si,Patrick Dupont,Annie-Claude Bayeul-Lainé,Antoine Dazin,Olivier Roussette,Gérard Bois 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.2

The overall performance of a vane-island type diffuser of a centrifugal pump model was obtained by means of directional probe traverses. These measurements were performed in an air model of a real hydraulic pump for five volume flow rates. Directional probe traverses are performed with a classical three-hole probe to cover most of the complete inlet section of the diffuser from hub to shroud and from pressure to suction side. Existing Particle image velocimetry (PIV) measurement results are also used to compare probe measurement results between the inlet and outlet throats of vane island diffuser at mid-span. Some assistance from already existing unsteady calculation, including leakage effects, is used to evaluate the numerical approach capability and to correctly define the mean initial conditions at impeller’s outlet section. Pressure recovery and the measured total pressure loss levels inside this particular vane diffuser geometry are then calculated. Detailed analysis of the flow structure at the inlet section of the vane island diffuser is presented to focus on pressure evolution inside the entire diffuser section for different flow rates. The combined effects of incidence angle and blockage distributions along hub to shroud direction are found to play an important role on loss distribution in such a diffuser.

Immunomodulation by a Malleable Matrix Composed of Fermented Whey Proteins and Lactic Acid Bacteria

Pierre Lemieux,Josoe Beaulieu,Roger Dubuc,Nicolas Beaudet,Claude Dupont 한국식품영양과학회 2007 Journal of medicinal food Vol.10 No.1

Functional foods and nutraceuticals have gained in popularity over the last 10 years. Among natural healthproducts, whey proteins and fermented milk products are paramount. A malleable protein matrix (MPM), composed of wheyfermented by a lactic acid bacterium, capsular exopolysaccharides, vitamins, minerals, and peptides generated during the fer-mentation process, has the potential to be unique by combining multiple health-promoting components. Forced feeding ex-periments on healthy animals were performed to evaluate the immunomodulatory effect of MPM. Glutathione production, an-consumption was evident as seen by the increased polymorphonuclear cell counts and intracellular glutathione levels. The ab-sence of MPM-specific antibody production indicated a lack of undesirable immune recognition of MPM. The MPM, with itsimmunomodulatory properties, has the potential to be a food substitute or a functional food for maintenance of general im-mune health.