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CN-117104473-B - Conduit propeller

CN117104473BCN 117104473 BCN117104473 BCN 117104473BCN-117104473-B

Abstract

The invention provides a duct propeller which comprises a tube body, a propeller main body and protruding units, wherein at least one groove is formed in the inner wall of the tube body, the propeller main body is arranged in the tube body and located at one end of the tube body, the groove surrounds the central axis of the tube body and is in a spiral line, a plurality of protruding units are continuously and uniformly distributed in the groove along the spiral line of the groove, adjacent protruding units are connected end to end, the groove in the spiral line shape is formed in the inner wall of the tube body, and the wake flow of the propeller is rectified through the groove, so that the circumferential velocity component of the wake flow gradually decreases under the action of the groove when the wake flow flows towards the outlet of the free end of the tube body, and the circumferential velocity component of the wake flow outlet end is obviously smaller than the circumferential velocity component of the wake flow inlet end, so that the purposes of improving the propulsion efficiency, reducing noise and the like are achieved.

Inventors

  • WU JIAFENG
  • Cao Heyun
  • CHEN WEI
  • HU XU
  • WEI WEI
  • LI XIANG
  • WANG WANYAN

Assignees

  • 中国船舶集团有限公司第七一九研究所

Dates

Publication Date
20260505
Application Date
20230920

Claims (7)

  1. 1. A ducted propeller, comprising: the inner wall of the pipe body (1) is provided with at least one groove (101); the paddle main body (2) is arranged in the pipe body (1) and is positioned at one end of the pipe body (1); A plurality of protruding units (3) are continuously and uniformly distributed in the groove (101) along the spiral line of the groove (101); the groove (101) surrounds the central axis of the pipe body (1) to form a spiral line, and the rotation direction of the spiral line of the groove (101) is the same as the rotation direction of the paddle main body (2); the adjacent protruding units (3) are connected end to end, and the cross section of each protruding unit (3) along the extending direction of the spiral line of the groove (101) is trapezoid or triangle; When the cross section of the protruding unit (3) is trapezoidal, the longer bottom edge of the protruding unit (3) is fixedly arranged on the bottom surface of the groove (101) and the shorter bottom edge of the protruding unit (3) faces the inside of the pipe body (1); when the cross section of the protruding unit (3) is triangular, one bottom edge of the protruding unit (3) is fixedly arranged on the bottom surface of the groove (101), and one corner of the protruding unit (3) faces the inside of the pipe body (1).
  2. 2. A catheter propeller according to claim 1, wherein the cross-section of the protruding unit (3) along the direction of the spiral line extension of the groove (101) is right trapezoid or right triangle, the extension line of the right-angle side of the protruding unit (3) is aligned with the center of the radial cross-section of the catheter body (1), and the hypotenuse of the protruding unit (3) faces the free end of the catheter body (1).
  3. 3. A catheter propeller according to claim 1, characterized in that the pitch of the groove (101) spiral increases in equal proportion in the direction of the propeller body (2) towards the free end of the tube body (1).
  4. 4. A catheter propeller according to claim 3, wherein the depth of the groove (101) increases in equal proportion with increasing pitch of the helix.
  5. 5. A ducted propeller according to claim 3, characterized in that the minimum pitch of the groove (101) helix is the same as the pitch of the propeller body (2).
  6. 6. A ducted propeller according to claim 1, wherein the length of the helical line of the groove (101) along the axial direction of the tube body (1) is not smaller than the distance between the blades of the main body (2) and the free end of the tube body (1).
  7. 7. A ducted propeller according to claim 1, characterized in that the duct body (1) comprises, The first pipe barrel (11) is provided with the groove (101) on the inner wall and is internally provided with the paddle main body (2); the second pipe barrel (12) is fixedly sleeved outside the first pipe barrel (11); Wherein the first tube (11) is made of sound absorbing material.

Description

Conduit propeller Technical Field The invention relates to the technical field of aircraft propellers, in particular to a conduit propeller. Background The conduit propeller consists of a propeller and a cylindrical flow guide pipe arranged outside the propeller, is used as an underwater propulsion mode and is widely applied to the fields of water surface ships, underwater submarines and the like. Compared with the common propeller, the conduit propeller has the advantages of protecting the propeller, improving the propulsion efficiency, reducing noise and the like. The continuous development of the ship industry brings forward higher requirements on hydrodynamic performance and acoustic performance for practical applications such as surface ships, underwater submarines and the like, so that the development and innovation of propulsion technologies such as conduit propellers and the like are required. The wake of the propulsion device is divided into an axial velocity component and a circumferential velocity component. In order to increase the propulsion efficiency and acoustic performance of the propulsion device as much as possible, it is desirable that the outflow has only an axial velocity component and no circumferential velocity component. Therefore, it is necessary to develop a flow control technique for rectifying the wake flow by some means, so as to reduce the circumferential velocity component of the wake flow as much as possible, thereby achieving the purposes of improving the propulsion efficiency, reducing noise, and the like. In addition, tip vortex of the propeller is one of the main sources of flow noise of the propulsion device, which needs to be controlled. The small gap between the duct of the ducted propeller and the blade tip is referred to as blade tip clearance, when the propeller operates, the front part of the blade forms a suction area, the rear part generates a pressure area, fluid is transferred to the suction area along the blade tip through blade tip clearance under the action of pressure difference, and interacts with low-pressure fluid after entering the suction area, so that high-strength vortex is generated, which is referred to as blade tip clearance vortex shedding, and the flow is referred to as blade tip clearance flow (TLV). There is a complex flow in the ducted propeller blade tip clearance where vortices of various sizes alternate out, and this unstable blade tip clearance vortex not only affects the efficiency of the propeller, but also is prone to erosion damage to the propeller itself. In addition, the existence of blade tip clearance vortex is easy to generate cavitation in the low-pressure area of the vortex core to form cavitation bubbles, and noise generated when the propeller works can be directly increased after the cavitation bubbles are generated. Therefore, how to reduce the circumferential velocity component of wake and reduce the adverse effect of blade tip clearance vortices is an important topic of ducted propeller development and design. Disclosure of Invention In view of this, the present invention proposes a ducted propeller for solving the problem of how to reduce the circumferential velocity component of the wake of the ducted propeller and to reduce the adverse effect of blade tip clearance vortices on the ducted propeller. The technical scheme is that the catheter propeller comprises a tube body, wherein at least one groove is formed in the inner wall of the tube body, a propeller main body is arranged in the tube body and located at one end of the tube body, and the groove surrounds the central axis of the tube body and is in a spiral line. On the basis of the technical scheme, the device preferably further comprises a plurality of protruding units which are continuously and uniformly distributed in the groove along the spiral line of the groove, wherein the adjacent protruding units are connected end to end. Still more preferably, the cross section of the protruding unit along the extending direction of the groove spiral line is trapezoid or triangle, when the cross section of the protruding unit is trapezoid, the longer bottom edge of the protruding unit is fixedly arranged on the bottom surface of the groove and the shorter bottom edge of the protruding unit faces the inside of the pipe body, and when the cross section of the protruding unit is triangle, one bottom edge of the protruding unit is fixedly arranged on the bottom surface of the groove and one corner of the protruding unit faces the inside of the pipe body. Still more preferably, the cross section of the protruding unit along the extending direction of the groove spiral line is in a right trapezoid or a right triangle, the extension line of the right-angle side edge of the protruding unit is aligned with the center of the radial cross section of the pipe body, and the bevel edge of the protruding unit faces the free end of the pipe body. On the basis of the technical scheme, pr