Ship propulsion performance heavily depends on cavitation,increasing the recent interest in this field to lower ship emissions.Academic research on the effects of cavitation is generally based on the open-water propel...Ship propulsion performance heavily depends on cavitation,increasing the recent interest in this field to lower ship emissions.Academic research on the effects of cavitation is generally based on the open-water propeller performance but the interactions of the cavitating propeller with the ship hull significantly affect the propulsion performance of the ship.In this study,we first investigate the INSEAN E779A propeller by a RANSE-based CFD in open-water conditions.The numerical implementation and the selected grid after sensitivity analysis partially succeeded in modeling the cavitating flow around the propeller.Satisfactory agreement was observed compared to experimental measurements.Then,using the open-water data as input,the propeller’s performance behind a full-scale ship was calculated under self-propulsion conditions.Despite being an undesired incident,we found a rare condition in which cavitation enhances propulsion efficiency.Atσ=1.5;the propeller rotation rate was lower,while the thrust and torque coefficients were higher.展开更多
In order to study the cavitation and hydrodynamic characteristics of propeller under uniform and non-uniform flows,numerical investigations are performed using interPhaseChangeDyMFoam in the open source computational ...In order to study the cavitation and hydrodynamic characteristics of propeller under uniform and non-uniform flows,numerical investigations are performed using interPhaseChangeDyMFoam in the open source computational fluid dynamics(CFD)software platform OpenFOAM with Schnerr-Sauer cavitation model.The simulation results can be used as a reference to evaluate the working ability of a propeller in case of actual navigation.A new grid encryption method is adopted in the research to better capture the existence of vortex cavitation at the propeller tip.The method of function input is carried out in the study to simulate the condition of non-uniform flow and reduce the calculation amount.Typical unsteady dynamics are predicted by the Reynolds-averaged Navier-Stokes(RANS)method with a modified shear stress transport(SST)k−ωturbulence model.The numerical results of the propeller such as cavitation shape and pressure distribution under uniform and non-uniform flow are analyzed and compared with each other.展开更多
文摘Ship propulsion performance heavily depends on cavitation,increasing the recent interest in this field to lower ship emissions.Academic research on the effects of cavitation is generally based on the open-water propeller performance but the interactions of the cavitating propeller with the ship hull significantly affect the propulsion performance of the ship.In this study,we first investigate the INSEAN E779A propeller by a RANSE-based CFD in open-water conditions.The numerical implementation and the selected grid after sensitivity analysis partially succeeded in modeling the cavitating flow around the propeller.Satisfactory agreement was observed compared to experimental measurements.Then,using the open-water data as input,the propeller’s performance behind a full-scale ship was calculated under self-propulsion conditions.Despite being an undesired incident,we found a rare condition in which cavitation enhances propulsion efficiency.Atσ=1.5;the propeller rotation rate was lower,while the thrust and torque coefficients were higher.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51879159,51809169 and 51909160)the National Key Research and Development Program of China(Grant Nos.2019YFB1704200,2019YFC0312400)the Chang Jiang Scholars Program(Grant No.T2014099)and the Innovative Special Project of Numerical Tank of Ministry of Industry and Information Technology of China(Grant No.2016-23/09).
文摘In order to study the cavitation and hydrodynamic characteristics of propeller under uniform and non-uniform flows,numerical investigations are performed using interPhaseChangeDyMFoam in the open source computational fluid dynamics(CFD)software platform OpenFOAM with Schnerr-Sauer cavitation model.The simulation results can be used as a reference to evaluate the working ability of a propeller in case of actual navigation.A new grid encryption method is adopted in the research to better capture the existence of vortex cavitation at the propeller tip.The method of function input is carried out in the study to simulate the condition of non-uniform flow and reduce the calculation amount.Typical unsteady dynamics are predicted by the Reynolds-averaged Navier-Stokes(RANS)method with a modified shear stress transport(SST)k−ωturbulence model.The numerical results of the propeller such as cavitation shape and pressure distribution under uniform and non-uniform flow are analyzed and compared with each other.
