CN202244050U

CN202244050U - Reaction fin in front of oar

Info

Publication number: CN202244050U
Application number: CN2011202999125U
Authority: CN
Inventors: 周志勇; 陈康; 魏菲菲; 林洁
Original assignee: Shanghai Merchant Ship Design and Research Institute
Current assignee: Shanghai Merchant Ship Design and Research Institute
Priority date: 2011-08-17
Filing date: 2011-08-17
Publication date: 2012-05-30
Anticipated expiration: 2021-08-17

Abstract

The utility model relates to a reaction fin in the front of an oar, which is installed on a conventional dextrorotation single-oar ship and belongs to the technical field of ship body energy-saving equipment. Seen from the back side of a propeller, a first fin (1), a second fin (2) and a third fin (3) are arranged on a stern on the left side of a longitudinal central line of a propeller hub (6) from top to bottom, and a fourth fin (4) is arranged on the right side. The included angle alpha of the first fin (1) and the longitudinal central line ranges from 46 degrees to 53 degrees, the included angle beta of the second fin (2) and the horizontal direction ranges from 1 degree to 8 degrees, the included angle x of the third fin (3) and the longitudinal central line ranges from 37 degrees to 44 degrees, and the included angle delta of the fourth fin (4) and the horizontal line ranges from 82 degrees to 89 degrees. By adopting the structure, three fins of the four fins are distributed in a low value area, namely a high speed area, of a wake field, so that adverse effect on flow of a low speed area caused by resistance of the fins is reduced. In addition, the fins distributed in the high speed area enable a flow field in front of the oar to rotate in advance, and simultaneously is beneficial to homogenization of the wakes.

Description

Reaction fin before the oar

Technical field

The utility model reacts fin before relating to a kind of oar, refers in particular to, and is installed on the preceding reaction of the oar fin of conventional dextrorotation single-blade ship, belongs to hull energy-saving equipment technical field.

Background technology

Reaction fin (being called for short R.F.) is a kind of guiding device that is contained in loose type single-blade marine propeller the place ahead, and as the stationary spiral oar that has than multiple-blade, it can reduce rotatablely moving of propeller current, thereby can save the power of marine main engine.The reaction fin becomes the fin leaf of certain angle of attack to form by some with current; Current are changed the original flow direction after flowing through the fin leaf; Formed one and the propeller race current of prewhirling in the opposite direction, played and reduced the effect of propeller race rotating energy loss, thereby reached purpose of energy saving.

Domestic and international research has recognized that the direction through changing the screw propeller influent stream can improve propulsion coefficient, and the reaction fin has carried out correlative study before the oar that 6 fins are arranged symmetrically, selects and the improvement of the correlation parameter of fin such as the aerofoil profile of fin; And on this basis, the correlative study personnel remove 1 to 2 in 6 fins, reaction fin before the oar that asymmetric arrangement that develops.These two kinds reaction fins all have two fins that horizontal direction is provided with; But owing to the flow field of the screw propeller existence that rotation is arranged behind the ship is whole is non-symmetrical fully, though therefore aforementioned two kinds of reaction fins can reach certain energy-saving effect, saves power 2%～4%; But the homogeneity of wake and the lost aspect that reclaims rotating energy in the propeller race be defectiveness still; And along with the conventional hull bottom is tending towards the development tendency of hypertrophyization, the wake field of stern top and the bottom is seriously inhomogeneous, in the propeller race rotating energy scatter and disappear serious; Therefore, the reaction fin can not address the above problem before the existing oar.

The utility model content

The utility model technical matters to be solved is to provide reaction fin before a kind of oar, through changing the turn of tidal stream field of prewhirling before flow field direction produces oar, thereby reaches the minimizing degradation of energy, improves the purpose of propeller propulsive efficiency.

For this reason, the technical scheme that the utility model provides is reaction fin before a kind of oar; It is characterized in that: behind screw propeller, look sideways; The stern in propeller hub longitudinal centerline left side is provided with first fin, second fin and the 3rd fin from top to bottom, and the right side is provided with the 4th fin, wherein; The scope of the angle of first fin and longitudinal centerline is 46 °≤α≤53 °; The scope of the angle β of second fin and horizontal direction is 1 °≤β≤8 °, and the scope of the angle χ of the 3rd fin and longitudinal centerline is 37 °≤χ≤44 °, and the scope of the angle δ between the 4th fin and the horizon is 82 °≤δ≤89 °.

Adopt said structure; Three low values that are distributed in the wake field in four fins are high-speed region; The resistance that has reduced fin is to the mobile adverse effect that causes of low-speed region, and the fin that is arranged in high velocity also helps the uniformization of wake when the preceding flow field of oar is rotated in advance.This design has also broken through the constraint of traditional design theory to those skilled in the art.

According to the plentiful degree of ship, the difference of the speed of a ship or plane, said fin be shaped as the airfoil type section, the shape of fin can be the smaller aerofoil profile of drag by lift in the NACA aerofoil profile, but will notice that the requirement of anchoring strength considers as a whole.

Further improve and be; The fin root of three fins in left side and the angle ε of propeller axis progressively increase from top to bottom; Its scope is 12 °≤ε≤21 °, the angle of the 4th fin fin root and propeller axis greater than the angle of second fin fin root and propeller axis less than the angle of the 3rd fin fin root and propeller axis.Can improve the propulsion coefficient of screw propeller so better.

Further improving is that the length of said four fins is 90%～105% of propeller radius again.Can guarantee good energy-saving effect like this.

To sum up, the beneficial effect of the utility model is: through producing a circumferential induced velocity field opposite with the screw propeller hand of rotation, thereby reduce in the propeller wake field because of the energy of spin loss, improve propeller propulsive efficiency; Make wake more be tending towards evenly making screw propeller work more steady, reduce the ship vibration risk that propeller exciting force causes; Improved the propeller cavitation performance.

Tank experiment proves that under the situation that layout angle, aerofoil profile and the setting angle of fin are realized distributing rationally, the energy-saving effect of the utility model reaches 4%～7%.

Contrast test evidence the utility model technical scheme of on 6 ton bulge carriers, carrying out improves propulsion coefficient and reaches 5.3%.Existing 6 ton bulge carriers consume 30 tons of diesel oil every day, adopt the utility model technical scheme, can save 0.6 ton of diesel oil every day, greatly reduce energy consumption.

Description of drawings

Below in conjunction with accompanying drawing the technical scheme of the utility model is done further detailed description:

Fig. 1 is the installation site scheme drawing of fin in the utility model.

Fig. 2 is the angle scheme drawing of fin and propeller axis direction in the utility model.

Fig. 3 is the shape scheme drawing of fin in the utility model.

Fig. 4 is the scheme drawing that the hull stern part of the utility model is installed.

The specific embodiment

As depicted in figs. 1 and 2, the reaction fin is looked sideways behind screw propeller before a kind of oar; The stern in propeller hub 6 longitudinal centerlines left side is provided with three fins; Be first fin 1, second fin 2 and the 3rd fin 3 from top to bottom, the right side is provided with the 4th fin 4, wherein; The scope of first fin 1 and the angle of longitudinal centerline is 46 °≤α≤53 °; The scope of second fin 2 and the angle β of horizontal direction is 1 °≤β≤8 °, and the scope of the 3rd fin 3 and the angle χ of longitudinal centerline is 37 °≤χ≤44 °, and the scope of the angle δ between the 4th fin 4 and the horizon is 82 °≤δ≤89 °.

The shape of fin is chosen the smaller aerofoil profile of drag by lift in the NACA aerofoil profile, but will notice that the requirement of anchoring strength considers as a whole.Its intensity need be adjusted according to the suffered live load of fin.Fig. 3 is the example of the shape of fin, said fin be shaped as the airfoil type section.

In conjunction with Fig. 2; The fin root of three fins in hull left side and the angle ε of propeller axis progressively increase from top to bottom; Its scope is 12 °≤ε≤21 °, the angle of the 4th fin 4 fin root and propeller axis greater than the angle of second fin, 2 fin roots and propeller axis less than the angle of the 3rd fin 3 fin roots and propeller axis.

The length of fin also will could guarantee good energy-saving effect in certain scope, the outer end of fin will be in the scope of 90%R-105%R, and wherein R is a propeller radius.

Combine the complete targetedly asymmetric arrangement scheme of flow field characteristics can reach the raising propeller propulsive efficiency better in the utility model, evenly wake and the purpose of improving propeller cavitation are a kind of feasible practical applications schemes.

Claims

1. react fin before an oar; It is characterized in that: behind screw propeller, look sideways; The stern in propeller hub (6) longitudinal centerline left side is provided with first fin (1), second fin (2) and the 3rd fin (3) from top to bottom, and the right side is provided with the 4th fin (4), wherein; The scope of the angle of first fin (1) and longitudinal centerline is 46 °≤α≤53 °; The scope of the angle β of second fin (2) and horizontal direction is 1 °≤β≤8 °, and the scope of the 3rd fin (3) and the angle χ of longitudinal centerline is 37 °≤χ≤44 °, and the scope of the angle δ between the 4th fin (4) and the horizon is 82 °≤δ≤89 °.

2. reaction fin before the oar according to claim 1 is characterized in that: said fin be shaped as the airfoil type section, profile type adopts the asymmetric airfoil in the NACA series.

3. reaction fin before the oar according to claim 1; It is characterized in that: the fin root of three fins in left side and the angle ε of propeller axis progressively increase from top to bottom; Its scope is 12 °≤ε≤21 °, the angle of the 4th fin (4) fin root and propeller axis greater than the angle of second fin (2) fin root and propeller axis less than the angle of the 3rd fin (3) fin root and propeller axis.

4. reaction fin before the oar according to claim 1, it is characterized in that: the length of said four fins is 90%～105% of propeller radius.