JP3519541B2 - Marine stator fin device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is arranged behind a propeller at a stern to recover turning energy in the wake of a propeller and to improve propulsion performance. The present invention relates to a stator fin device. 2. Description of the Related Art As a conventional marine stator fin device, there are those shown in FIGS. 4 (a stern side view) and FIG. 5 (a view taken along the line DD in FIG. 4 ). At the rear of the propeller 2, a fin boss 4 of a stator fin is fixed to a rudder horn 3 protruding downward from the hull so that a rudder 6 can be mounted, and a plurality of fins 5 projecting radially from the fin boss 4 are formed by a propeller. A twist or an inclination is provided in a direction for recovering the swirling energy in the wake. The lengths of the fins 5 are all equal. [0003] By the way, when the swirl flow of a model ship having a clockwise propeller at the stern was measured immediately after the propeller, the situation seen from behind was shown in FIG.
The result was as shown in FIG. As is clear from FIG. 6 , in the clockwise propeller, the center of the swirling flow is deviated leftward with respect to the propeller axis center line. That is, during the forward rotation of the clockwise propeller, the center of the swirl flow is biased toward the ascending side of the propeller blades. When the propeller is provided with a counterclockwise propeller at the stern, it is clear that the center of the swirling flow generated behind the propeller is deviated to the right with respect to the propeller axis center line. The central part of the swirling flow is biased toward the ascending side. Therefore, when the center of the fin boss 4 is disposed on the rearward extension of the center line of the propeller shaft and the lengths of the fins are made equal to each other as in the conventional marine stator fin device, turning in the wake of the propeller There is a problem that the function of recovering energy is not sufficiently performed. Therefore, the present invention focuses on a phenomenon in which the center of the swirl flow in the wake of the propeller is deviated laterally during forward rotation of the stern propeller, and appropriately sets the fin length of the stator fin. Accordingly, it is an object of the present invention to provide a marine stator fin device capable of efficiently recovering turning energy in a wake of a propeller and improving propulsion performance. [0006] In order to solve the above-mentioned problems, a marine stator fin device of the present invention comprises a stator fin mounted on a rudder horn protruding downward from a hull behind a propeller at a stern. The fin boss is attached, and a plurality of fins radially protruding from the fin boss are provided with a twist or an inclination capable of collecting turning energy in the wake of the propeller at the time of forward rotation of the propeller, and the propeller is moved forward. The fin length on the rising side of the propeller blade during rotation is set to be longer than the fin length on the descending side of the propeller blade. In the above-described marine stator fin device, the length of the fin on the deviating side is set to be longer than the length of the fin on the opposite side in order to cope with the fact that the central portion of the swirling flow in the wake of the propeller is deviated laterally. As a result, the turning energy in the wake of the propeller can be accurately recovered, and a significant improvement in propulsion performance is expected. DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the embodiments of the present invention will be described with reference to the drawings, FIG. 1 is a stern front view showing a marine stator fin device as an embodiment of the present invention, FIG. 2
Is a side view of the stern portion of FIG. 1, FIG. 3 is Ru <br/> Ah at A-A arrow view of FIG. As shown in FIGS. 1 and 2, also in the present embodiment, a rudder horn 3 protruding downward from the hull so that a rudder 6 can be mounted behind the propeller 2 of the stern 1.
The fin bosses 4 of the stator fins are fixed to the fins 4, and the fins 5 projecting radially from the fin bosses 4 are twisted or inclined in a direction capable of recovering the turning energy in the wake of the propeller. In this embodiment, in particular, the propeller 2 is turned clockwise during forward rotation, and the length of the fin 5 is set as follows in accordance with this. That is, propeller 2
Side on which propeller blade 2a rises during forward rotation of port (port side)
As shown in FIGS. 1 and 3, the fin 5 is set to have a fin length longer than the fin on the opposite side (the starboard side where the propeller blades descend). As a result, as shown in FIG. 6 , the center of the swirling flow in the wake of the propeller is deviated to the port side where the propeller blades rise, as shown in FIG. The distribution of 5 also becomes deviated to the port side and matches the distribution of the swirling flow, so that the swirling energy contained in the swirling flow in the wake of the propeller at the time of forward rotation of the propeller 2 is appropriately recovered. Therefore, significant improvement in propulsion efficiency is expected. [0012] Incidentally, although the propeller 2 in the implementation form of the above mentioned is provided as biased to the port side as a whole stator fins because that is a clockwise type, when the propeller 2 is counterclockwise type, since the center of the swirling flow of the propeller slip stream is biased to the right side relates to the propeller shaft centerline, the stator fins also have long comb fins length starboard side, so that the entire stator fin relates propeller shaft center line is biased to the starboard side It is needless to say that the same operation and effect can be obtained. [0013] As has been described above in detail, according to the marine stator fin device of the present invention, the center of the swirling flow is to deal with the biased lateral in-flow after propeller, side thereof biased Since the length of the fin is set to be longer than the length of the fin on the opposite side, the turning energy in the wake of the propeller can be accurately recovered, and significant improvement in propulsion performance can be expected .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a stern front view showing a marine stator fin device as one embodiment of the present invention. FIG. 2 is a side view of the stern of FIG. 1; FIG. 3 is a view as viewed in the direction of arrows AA in FIG. 2; FIG. 4 is a stern side view showing a conventional marine stator fin device. FIG. 5 is a view taken in the direction of the arrows D in FIG. 4 ; FIG. 6 is an explanatory diagram showing a distribution of a swirling flow in a stern propeller wake. [Description of Signs] 1 Stern 2 Propeller 2a Propeller wing 3 Rudder horn 4 Fin boss 5 Fin 6 Rudder

Claims (1)

(57) [Claim 1] A fin boss of a stator fin is mounted on a rudder horn protruding downward from a hull behind a propeller at a stern, and a plurality of fin bosses radially protrude from the fin boss. The fin of the propeller is provided with a twist or inclination capable of recovering the turning energy in the wake of the propeller at the time of forward rotation of the propeller, and the fin length on the rising side of the propeller blade at the time of forward rotation of the propeller is The fin length is set longer than the fin length of the descending side of the fin.