Thrust Characteristics and Nozzle Role of Water Jet Propulsion

DOI
  • Ni Yongyan
    School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology
  • Liu Weimin
    School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology
  • Shen Zhanhao
    National Research Centre of Pumps, Jiangsu University
  • Pan Xiwei
    National Research Centre of Pumps, Jiangsu University

Description

Surface pressure integration and momentum method were respectively performed to evaluate the impeller thrust and the system thrust of a contra-rotating axial flow water jet propulsion, and an interesting phenomenon so-called thrust paradox was revealed. To explain the paradox, the impeller thrust and the system thrust were physically and theoretically analyzed, the results show that the impeller thrust is head involved and is determined by the hydraulic parameters upstream and downstream the impeller, while the momentum method depicted by a classic equation is valid simply under the best efficiency point. Consequently, the role of a water jet propulsion nozzle was deduced that the nozzle is mainly to limit the flow rate that crosses the impeller and to assure the system working under the best efficiency condition apart from its ability to produce momentum difference. Related mathematical formula expressed the nozzle diameter is the dominant variable used to calculate the working condition of the water jet propulsion. Therefore the nozzle diameter can be steadily estimated by the former expression. The system thrust scaling characteristics under various speeds were displayed lastly.

Journal

Keywords

Details 詳細情報について

  • CRID
    1390001205297490688
  • NII Article ID
    130005395313
  • DOI
    10.5293/ijfms.2017.10.1.047
  • ISSN
    18829554
  • Text Lang
    en
  • Data Source
    • JaLC
    • Crossref
    • CiNii Articles
  • Abstract License Flag
    Disallowed

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