High-altitude propeller and propeller tip winglet capable of improving efficiency of high-altitude propeller

A technology of efficiency and blades, applied in propellers, aircraft parts, transportation and packaging, etc., can solve the problems of increasing propeller energy loss, reducing the effective angle of attack of each blade position, and reducing propeller efficiency

CN104139849AActive Publication Date: 2014-11-12NORTHWESTERN POLYTECHNICAL UNIV
7 Cites 19 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2014-11-12

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses a high-altitude propeller and a propeller tip winglet capable of improving efficiency of the high-altitude propeller. The propeller tip winglet is of an upswept winglet form and comprises a winglet straight plate section and a winglet transition section, wherein the height of the propeller tip winglet is 3%-4% of the length of half propeller diameter of a base propeller; the height of the winglet straight plate section is 2%-3% of the half propeller diameter of the base propeller; the length of an end side stance wing-shaped chord of the propeller tip winglet is 60%-65% of the length of a propeller tip stance wing-shaped chord of the base propeller; the length of an intersection stance wing-shaped chord is 73%-78% of the length of a propeller tip stance wing-shaped chord of the base propeller; a torsion angle of the winglet straight plate section is 3-5 degrees smaller than a propeller tip stance wing-shaped torsion angle of the base propeller; a front edge sweepback angle of the propeller tip winglet is 10-15 degrees smaller than that of the propeller tip of the base propeller; an inclination angle of the propeller tip winglet is 35-45 degrees. The propeller tip winglet is capable of effectively reducing the strength of the inductive vortex of the propeller tip, reducing the energy dissipation of a screw propeller and finally effectively improving the working efficiency of a high-altitude propeller propelling system.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention belongs to the technical field of propeller design, and in particular relates to a blade tip winglet and a high-altitude propeller capable of improving the efficiency of the high-altitude propeller. Background technique

[0002] The high-altitude aircraft uses electric energy converted from solar energy as the main energy source. The design goal is to hover at a fixed point for a long time or maneuver at a low speed within an altitude of about 20km. The "Helios" series of high-altitude and long-endurance UAVs all use propellers as propulsion devices. As the flight altitude increases, the Reynolds number decreases significantly, that is, the high-altitude propeller is in a low Reynolds number working state, and the propeller efficiency will be significantly reduced. Therefore, improving the aerodynamic efficiency of the high-altitude propeller is of great significance for high-altitude aircraft.

[0003] For conventional layout propellers...

Examples

Embodiment Construction

[0030] The present invention is described in detail below in conjunction with accompanying drawing:

[0031] The present invention provides a blade tip winglet and a high-altitude propeller with improved high-altitude propeller efficiency, wherein the high-altitude propeller is a propeller suitable for a working height of 15-20 km, such as figure 1 with figure 2 As shown, the high-altitude paddle is made up of three parts, the paddle hub 7, the basic blade and the paddle-tip winglet. Wherein, 4 represents the upper surface of the basic blade, 5 represents the trailing edge of the basic blade, 6 represents the leading edge of the basic blade, and 9 represents the lower surface of the basic blade. The propeller hub 7 is provided with a propeller mounting hole 8 . The paddle-tip winglet is in the form of an upturned winglet, which is composed of a winglet straight plate section 1 and a winglet transition section 2 .

[0032] Since the geometric structure parameters of the pad...