CN2214354Y

CN2214354Y - Propeller cap with appropriately run flow wing board

Info

Publication number: CN2214354Y
Application number: CN94239233U
Authority: CN
Inventors: 华汉金; 钱文豪
Original assignee: 708 Research Institute Of Seventh Research Institute Of China Shipbuilding Corp
Current assignee: 708 Research Institute Of Seventh Research Institute Of China Shipbuilding Corp
Priority date: 1994-08-18
Filing date: 1994-08-18
Publication date: 1995-12-06
Anticipated expiration: 2004-08-18

Abstract

The utility model relates to a propeller cap with appropriately run flow wing board. The propeller cap with appropriately run flow wing board is characterized in that the propeller cap is provided with spiral wing boards which have the same quantity with the propeller blades, and then the water stream attacking angle positioned at the radius of each wing board can reach to the optimum water stream attacking angle state. Therefore, the increasing quantity of the propulsive efficiency obtained by the spiral wing board is larger than the flat wing board.

Description

Propeller cap with appropriately run flow wing board

The utility model relates to a kind of improvement of the screw propeller spinner with fin keel.

Existing screw propeller spinner mostly is a fleetline cone, tangential induction velocity is generally 0.5～0.8 times of screw propeller influent stream speed near propeller hub, account for 1/3 of propeller race rotation function, this part energy will be converted into the hub vortex cavity and lose and will cause vacuolus denudation to the rudder behind the oar.Name is called the Chinese patent of " propeller spinner of band fin keel " (publication number is CN 1031975A), be that the mechanism that some plate shaped fins form water turbine is installed on spinner, reclaimed near a part of rotating energy of propeller hub, thereby improved the propulsion coefficient of screw propeller and reduced hub vortex cavity noise.But because near the variation of the tangential induction velocity propeller hub is very violent, the more little this variation Shaoxing opera of hub diameter is strong, only the plate fin keel of installing with certain inclination angle is as the words of the blade of water turbine, too the current angle of attack at finlet plate taper place is too big with the current angle of attack that causes fin keel root place, be not in best current angle of attack state, thereby make the increment of propulsion coefficient little.

Accompanying drawing 5 is that current are axially and the tangential velocity distribution behind the screw propeller of actual measurement gained of a certain bulge carrier.Va among the figure, Ve and V ∞ are respectively the current axial velocity, and tangential velocity and oar front axle be to influent stream speed, Va, the spin velocity of Ve and oar synthesizes a hydrodynamic pitch angle, and tangential velocity variation is very violent as seen from Figure 5.

The purpose of this utility model is that a kind of screw propeller spinner with suitable influent stream fin keel will be provided, the shape of the fin keel on this spinner and installation site thereof make the current angle of attack at fin keel different radii place roughly all be in the best water flow angle of attack, thereby can improve propeller efficiency significantly.

The utility model is to realize like this, form by screw propeller spinner and some fin keels mounted thereto, propeller blade number before the quantity of fin keel and the spinner equates, it is characterized in that: the shape of fin keel is the helical surface shape, from the fin keel root to the fin keel taper, the descending variation of geometric pitch angle of each radius.

Description of drawings is as follows:

Fig. 1 is equipped with the front elevation (seeing to bow) of the screw propeller of the screw propeller spinner of being with suitable influent stream fin keel

Fig. 2 is equipped with the lateral plan of the screw propeller of the screw propeller spinner of being with suitable influent stream fin keel

Fig. 3 is I-I cutaway view

Fig. 4 is II-II cutaway view

Fig. 5 is the distribution of the axial and tangential velocity of a certain bulge carrier spinner place actual measurement gained.

Below in conjunction with the accompanying drawing structure of the screw propeller spinner of the suitable influent stream fin keel of oolemma specifically, on the back spinner 3 of propeller hub 4 some fin keels 2 are set on the quarter like that as depicted in figs. 1 and 2, the quantity of the propeller blade 1 before the quantity of fin keel 2 and the spinner 3 equates, the shape of fin keel 2 be the helical surface shape from the fin keel root to taper, the geometric pitch angle of each radius is descending, fin keel root geometric pitch angle is 40 °～90 °, it is good that fin keel taper geometric pitch angle is 20 °～70 °, fin keel 2 is installed near the midway location between the extended surface of pitch surface of root of two adjacent blades 1, the chord length of fin keel is not to stretch out spinner front/rear end degree of being, the section of fin keel 2 is the symmetry machine aerofoil profile.

(one is bulge carrier to the screw propeller spinner of the suitable influent stream fin keel of band described in the utility model through the oar mould test of three class ships, one is box ship and a high speed vessel), the increment of the propulsion coefficient of measuring is respectively 9.6%, 6.5% and 6.9% increment than the propulsion coefficient of the described device of CN1031975A Chinese patent and improves 2～3 percentage points.

Claims

1, a kind of screw propeller spinner with suitable influent stream fin keel, it is made up of screw propeller spinner (3) and the some fin keels (2) that are installed on the spinner (3), the quantity of fin keel (2) equates with the quantity of spinner 3 fwd propeller blades (1), fin keel (2) is installed near the midway location between the extended surface of blade root pitch surface of two adjacent propeller blades (1), it is characterized in that: the shape that is shaped as helical surface of fin keel (2), from the geometric pitch angle of fin keel root to each radius of fin keel taper from large to small.

2, the screw propeller spinner of the suitable influent stream fin keel of band as claimed in claim 1, it is characterized in that: the geometric pitch angle at the root place of fin keel (2) is 40 °～90 °, the geometric pitch angle at taper place is 20 °～70 °.