In the water jet propulsion system with a positive displacement （PD） pump, the nozzle, which converts pressure energy into kinetic energy, is one of the key parts exerting great influence on the reactive thrust and ...In the water jet propulsion system with a positive displacement （PD） pump, the nozzle, which converts pressure energy into kinetic energy, is one of the key parts exerting great influence on the reactive thrust and the efficiency of the system due to its high working pressure and easily occurring cavitation characteristics. Based on the previous studies of the energy loss and the pressure distribution of different nozzles, a model of water jet reactive thrust, which fully takes the energy loss and the nozzle parameters into consideration, is developed to optimize the nozzle design. Experiments and simulations are carried out to investigate the reactive thrust and the conversion efficiency of cylindrical nozzles, conical nozzles and optimized nozzles. The results show that the optimized nozzles have the largest reactive thrust and the highest energy conversion efficiency under the same inlet conditions. The related methods and conclusions are extended to the study of other applications of the water jet, such as water jet cutting, water mist fire suppression, water injection molding.展开更多
基金financially supported by the Natural Science Foundation of China(Grant No.51275495)the Open Research Fund of the State Key Laboratory of Fluid Power and Mechatronic Systems of Zhejiang University(Grant No.GZKF-201104)+4 种基金the State Key Laboratory of Ocean Engineering of Shanghai Jiao Tong University(Grant No.1105)the Key Laboratory of Technology for Safeguarding of Maritime Rights and Interests and Application(Grant No.SMZS-KCF-P2013012)the National High Technology Research and Development Program of China(863 Program,Grant No.2012AA091103)the Natural Science Foundation of Shandong Province(Grant No.ZR2011EEQ010)OUC-SRDP(Grant No.201210423081)
文摘In the water jet propulsion system with a positive displacement （PD） pump, the nozzle, which converts pressure energy into kinetic energy, is one of the key parts exerting great influence on the reactive thrust and the efficiency of the system due to its high working pressure and easily occurring cavitation characteristics. Based on the previous studies of the energy loss and the pressure distribution of different nozzles, a model of water jet reactive thrust, which fully takes the energy loss and the nozzle parameters into consideration, is developed to optimize the nozzle design. Experiments and simulations are carried out to investigate the reactive thrust and the conversion efficiency of cylindrical nozzles, conical nozzles and optimized nozzles. The results show that the optimized nozzles have the largest reactive thrust and the highest energy conversion efficiency under the same inlet conditions. The related methods and conclusions are extended to the study of other applications of the water jet, such as water jet cutting, water mist fire suppression, water injection molding.
