CN212267811U

CN212267811U - Underwater tandem type co-rotating propeller equipment

Info

Publication number: CN212267811U
Application number: CN202020769701.2U
Authority: CN
Inventors: 刘杨; 宫庆伟
Original assignee: Dalian University of Technology
Current assignee: Dalian University of Technology
Priority date: 2020-05-12
Filing date: 2020-05-12
Publication date: 2021-01-01
Anticipated expiration: 2030-05-12

Abstract

An underwater tandem type co-rotating propeller device belongs to the technical field of ships. The marine tandem type propeller comprises a propeller hub and blades, wherein the blades comprise a front blade and a rear blade, the front blade and the rear blade are sequentially arranged along the direction of a propeller axis A, and the blade stagger angle is zero. The diameter of the rear paddle is 0.95 times of that of the front paddle; the axial distance between the front propeller and the rear propeller is 0.30 times of the diameter of the front propeller. The rear propeller is positioned in the wake flow generated by the front propeller, has good absorption on the energy of wake vortexes generated by the front propeller, and has a contraction effect on the wake flow generated by the front propeller; compared with a series-connection type propeller with the same diameter of the front blade and the rear blade, the efficiency is greatly improved, and the series-connection type propeller has a good application prospect.

Description

Underwater tandem type co-rotating propeller equipment

Technical Field

The utility model belongs to the technical field of boats and ships, especially, relate to a serial-type is equipped with rotatory propeller under water with changeing.

Background

Currently, the most widely used marine propulsion devices are propeller thrusters. The propeller is a propulsion device with a disc-shaped helicoid, generally consists of a hub and adjacent blades fixed on the hub and having equal spacing angles, the propeller is driven by a main engine to rotate, the blades are used for stirring water backwards to receive reaction force, and the reaction force is transmitted to a ship body through a propeller shaft and a thrust bearing to push the ship to advance. Nowadays, most of propeller propellers applied to ships are single-propeller structure devices. With the continuous development of the ship industry, the scale of the ship is continuously increased, the magnitude of water drained by the ship body is gradually increased, and the traditional single-shaft single-propeller has the defects of small exposed thrust, low efficiency, easiness in generating a cavitation phenomenon, ship body vibration and the like. In view of the above problems, the Tandem propeller can be applied to production with the advantages of higher hydrodynamic efficiency, less vibration and noise (Q.Sun, Y.Gu, Tandem propellers for high power shifts, transformation of RINA 133(1991) 347-362). The tandem propeller thruster is characterized in that a front propeller and a rear propeller or a plurality of propellers with the same rotating direction are arranged on the same shaft. For ships with larger loads, higher thrust can be generated and higher efficiency can be achieved under the condition that the diameter of the propeller is limited due to draught. In addition, the stern vibration and cavitation caused by the single-shaft single-propeller can be improved. Before the series propeller is used, the diameters of the rear blades are the same, and the generated thrust is only improved by a small part. In view of the above-mentioned problems and drawbacks, there is a need for new improvements in the design of existing tandem propeller arrangements.

SUMMERY OF THE UTILITY MODEL

To the problem, the utility model provides a serial-type is with changeing propeller equipment under water. The utility model is characterized in that, the back oar diameter of serial-type screw propeller is less than preceding oar diameter, and preceding, back oar pitch diameter ratio equals. Under the design operating mode, weaken the cavitation bubble to the influence of propeller hydrodynamic performance, when improving thrust, raise substantially efficiency.

In order to achieve the technical purpose, the utility model discloses a technical scheme be:

the underwater tandem type co-rotating propeller equipment comprises a propeller hub and blades, wherein the blades comprise a front blade and a rear blade, the front blade and the rear blade are sequentially arranged along the direction of a propeller axis A, and the blade stagger angle is zero.

As a further improvement to the above, the diameter of the rear paddle is 0.95 times the diameter of the front paddle; the axial distance between the front blade and the rear blade is 0.30 times of the diameter of the front blade.

The utility model discloses a show the advantage and be: the marine tandem propeller comprises a propeller hub, a front propeller blade and a rear propeller blade, wherein the diameter of the rear propeller blade is 0.95 times of that of the front propeller blade, the axial distance between the front propeller blade and the rear propeller blade is 0.30 times of that of the front propeller blade, and the stagger angle of the propeller blades is zero. The rear propeller is positioned in the wake flow generated by the front propeller, has good absorption on the energy of wake vortexes generated by the front propeller, and has a contraction effect on the wake flow generated by the front propeller; compared with the tandem type propeller thruster with the same diameter of the front blade and the rear blade, the efficiency is greatly improved.

Drawings

FIG. 1 is a first cross-sectional view of a prior art;

FIG. 2 is a schematic cross-sectional view of a prior art;

FIG. 3 is a schematic sectional view of the present invention;

FIG. 4 is a schematic sectional view of the present invention;

FIG. 5 is a graph of the effect of the ratio of the axial distance of two propellers on the hydrodynamic efficiency of a tandem propeller;

fig. 6 is a graph of the effect of the ratio of the two-propeller diameter on the hydrodynamic efficiency of the tandem propeller propulsion.

In the figure: 1, a hub; 2, a front blade; 3 rear blade.

Detailed Description

The following further describes a specific embodiment of the present invention with reference to the drawings and technical solutions.

As shown in fig. 1 and 2, in the conventional single-shaft single propeller, the propeller axis is a', which is disadvantageous in that the thrust generated and the efficiency are low under the designed working conditions.

Referring to fig. 3-4, a tandem propeller for a ship includes a hub 1 and blades, the blades include a front blade 2 and a rear blade 3, the front blade 2 and the rear blade 3 are sequentially arranged in the fore-and-aft direction along a blade axis a, and a blade stagger angle is zero.

The diameter of the rear paddle is 0.95 times of the diameter of the front paddle, the axial distance between the front paddle and the rear paddle is 0.30 times of the diameter of the front paddle, and the pitch diameter ratio of the front paddle to the rear paddle is equal.

Referring to FIGS. 5-6, it can be seen that the hydrodynamic efficiencies of the tandem propellers are at L/D, respectively_f＝0.30；D_a/D_fWhen 0.95, the maximum value is obtained. Wherein, fig. 5 is a graph for investigating the influence of the axial distance between the front and rear blades on the hydrodynamic efficiency of the tandem propeller when the diameters of the front and rear blades are equal; fig. 6 is a graph for investigating the influence of the diameter ratio of the front and rear blades on the hydrodynamic efficiency of the tandem propeller under the condition that the axial distance between the front and rear blades is 0.29 times the diameter of the front blade. L is the axial distance between the front blade and the rear blade, D_fIs the diameter of the front blade, D_aIs the rear blade diameter, η₀The hydrodynamic efficiency of the tandem propeller is shown, and J is the advance speed coefficient of the tandem propeller.

The utility model discloses use and can use in following two aspects:

because the efficiency of the tandem type propeller thruster is obviously increased compared with the efficiency of a single-shaft single propeller thruster, when the original efficiency of the ship propeller thruster is improved, a single propeller can be converted into the tandem type propeller.

When the diameter of the ship propeller is limited due to low draught of a ship, a single propeller can be changed into a tandem propeller to increase the thrust and improve the efficiency, but the longitudinal space of the stern needs to be taken into consideration.

The above description specifically describes the preferred embodiments of the present invention, but it is not understood that the scope of the present invention is limited thereto, and it should be noted that, for those skilled in the art, many modifications and improvements can be made without departing from the scope of the present invention, and all of them belong to the protection scope of the present invention.

Claims

1. An underwater tandem type co-rotating propeller device comprises a propeller hub (1) and blades, and is characterized in that the blades comprise a front blade (2) and a rear blade (3), the front blade (2) and the rear blade (3) are sequentially arranged along the direction of a propeller shaft, and the blade stagger angle is zero; the diameter of the rear paddle (3) is 0.95 times of that of the front paddle (2).

2. An underwater tandem co-rotating propeller arrangement according to claim 1, wherein the axial distance between the front blade (2) and the rear blade (3) is 0.30 times the diameter of the front blade (2).