CN216185920U

CN216185920U - Underwater rotating propeller-shaft system water elasticity performance test device

Info

Publication number: CN216185920U
Application number: CN202122608179.7U
Authority: CN
Inventors: 李家盛; 张正艺; 刘曾; 宋磊; 金鑫; 李解
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2021-10-28
Filing date: 2021-10-28
Publication date: 2022-04-05
Anticipated expiration: 2031-10-28

Abstract

The utility model belongs to the technical field related to ship hydroelasticity or fluid-solid coupling mechanical tests, and discloses a hydroelasticity performance test device for an underwater rotating propeller-shaft system, which comprises: a motor, a torque thrust rotating speed testing system and an electromagnetic exciter are arranged in the open water tank; one end of the rotating shaft is arranged in the open water tank, the motor is arranged at the end part of the rotating shaft, and the torque thrust and rotating speed testing system and the electromagnetic exciter are arranged in the rotating shaft; the propeller is arranged at the other end of the rotating shaft, and the blades of the propeller and the rotating shaft are provided with acceleration sensors which are output to the data processing computer through a conductive slip ring at the end part of the rotating shaft; the open water tank, the rotating shaft and the propeller are arranged on the trailer. This application avoids the restriction of traditional screw yardstick, and the design accords with actual screw running state's test device more, and then can realize the accurate test of propeller shaft system water elasticity performance through installation sensor and vibration exciter cooperation.

Description

Underwater rotating propeller-shaft system water elasticity performance test device

Technical Field

The utility model belongs to the technical field related to ship hydroelasticity or fluid-solid coupling mechanical tests, and particularly relates to a hydroelasticity performance test device for an underwater rotating propeller-shaft system.

Background

The propeller-shaft system is a core component of a ship power propulsion device. The propeller generates a fluid-elastic paddle-shaft complex bidirectional fluid-solid coupling phenomenon when the propeller vibrates in a stern non-uniform wake field due to the elasticity of the blades and the rotating shaft. With the wide use of large-side inclined propellers and composite propellers, the bidirectional fluid-solid coupling effect of the fluid-elastic propeller-shaft complex system is more remarkable, as shown in fig. 1. The vibration of the elastic paddle-shaft system can not only damage various precision equipment on the ship, but also cause discomfort symptoms such as seasickness and the like to people on the ship, thereby being not beneficial to the safe operation of the ship. In addition, the vibration of the elastic paddle-shafting is an important source for generating low-frequency radiation noise under water of the ship. The research on the bidirectional fluid-solid coupling/hydro-elasticity phenomenon of the fluid-elastic paddle-shaft complex system has great significance on the problems of paddle-induced propulsion system vibration and ship body underwater radiation noise.

In the prior art, the steady stress characteristic of the ship propeller under uniform incoming flow and the dynamic characteristic (such as dynamic strain) of the rigid body propeller under non-uniform incoming flow are obtained and can be realized by arranging corresponding sensors. But the dynamic mechanical property test caused by considering the interaction of fluid and blade solid (relating to the elasticity of the blade and the rotating shaft) under the condition of non-uniform inflow is difficult to realize. The only research related to the hydro-elasticity problem of the screw will-shaft system is carried out in the vacuole water drum experimental environment. Due to the limitation of the size of the cavitation water cylinder, the size of the propeller for testing is limited, on one hand, the size effect of the test is increased, on the other hand, the size and the weight of the acceleration sensor used for testing can cause great interference to the vibration characteristic and the hydrodynamic characteristic of the propeller, the signal-to-noise ratio of the test bed is increased to a certain extent, and the research on the water elasticity law of the propeller-shaft system is not facilitated.

SUMMERY OF THE UTILITY MODEL

Aiming at the defects of the prior art, the utility model aims to provide a test device for the water elasticity performance of an underwater rotating propeller-shaft system, which avoids the limitation of the dimension of the traditional propeller, designs the test device which is more consistent with the actual running state of the propeller, and further can realize the accurate test of the water elasticity performance of the propeller-shaft system by installing a sensor and a vibration exciter in a matching way.

In order to achieve the above object, the present invention provides a device for testing the water elasticity performance of an underwater rotating propeller-shaft system, the device comprising: the device comprises an open water tank, wherein a motor, a torque thrust and rotating speed testing system and an electromagnetic exciter are arranged in the open water tank; one end of the rotating shaft penetrates through the wall surface of the open water tank and is arranged in the open water tank, the motor is arranged at the end part of the rotating shaft, the torque thrust rotating speed testing system and the electromagnetic exciter are arranged in the rotating shaft, and the electromagnetic exciter is in communication connection with the power amplifier and the signal generator; the propeller is arranged at the other end of the rotating shaft, and the blades of the propeller and the rotating shaft are provided with acceleration sensors which are output to a data processing computer through a conductive slip ring at the end part of the rotating shaft; the trailer moves in cooperation with a guide rail in the water pool, and the open water tank is arranged on the trailer.

Preferably, the conductive slip ring comprises a stator and a rotor which are arranged next to each other, the rotor is connected with the acceleration sensor through a cable, and the stator is connected with the data acquisition instrument through a cable and further connected with the data processing computer.

Preferably, the number of the acceleration sensors arranged on the blades is multiple, and the multiple acceleration sensors are uniformly arranged on the blades of the propeller.

Preferably, the distance between the position of the acceleration sensor arranged on the blade and the axis of the propeller is 0.6-0.9 r, wherein r is the radius of the blade.

Preferably, the distance between the propeller and the open tank is greater than 3 times the diameter of the propeller.

Preferably, a shaft sleeve is fixed on the open water tank, and the rotating shaft penetrates through the shaft sleeve.

Preferably, the end part of the propeller is provided with a fairing cap.

Through the technical scheme, compared with the prior art, the underwater rotating propeller-shaft system water elasticity performance test device provided by the utility model has the following beneficial effects:

1. the utility model discloses a water-proof tank, including the water-proof tank, the water-proof tank is equipped with the pump, the pump is equipped with the pump.

2. The electromagnetic exciter can provide longitudinal vibration, excitation frequency and amplitude of the excitation are easy to adjust, excitation of any frequency and amplitude can be output, excitation output can be adjusted conveniently in time, and test efficiency and precision are improved remarkably.

3. The conductive slip ring is designed in a form of combining the rotor and the stator, and the signal acquisition difficulty caused by the rotation of the propeller can be overcome.

4. The distance between the position of the acceleration sensor arranged on the paddle and the axis of the propeller is 0.6-0.9 r, so that the measurement of the acceleration of the paddle can be realized, and the interaction between the paddle and water cannot be influenced by the acceleration sensor.

Drawings

FIG. 1 is a schematic representation of a deformation of an elastic paddle-shaft system when operating in an unsteady flow field;

FIG. 2 is a schematic view of a hydro-elastic performance testing device for an underwater rotating propeller-shaft system;

FIG. 3 is a top view of the underwater rotating propeller-shaft system hydro-elastic performance testing device;

FIG. 4 is a front view of a conductive slip ring;

fig. 5 is a right side view of the conductive slip ring.

The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein:

the method comprises the following steps of 1-open water tank, 2-trailer, 3-motor, 4-torque thrust and rotation speed testing system, 5-electromagnetic exciter, 6-shaft sleeve, 7-rotating shaft, 8-propeller, 9-conductive slip ring, 10-acceleration sensor, 11-rectifying cap, 12-power amplifier, 13-signal generator, 14-data acquisition instrument, 15-data processing computer, 16-cable, 17-water tank, 18-guide rail, 19-stator and 20-rotor.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and are not intended to limit the utility model.

As shown in fig. 2 and fig. 3, the utility model provides a water elasticity performance testing device for an underwater rotating propeller-shaft system, which comprises an open water tank 1, a trailer 2, a motor 3, a torque thrust rotating speed testing system 4, an electromagnetic exciter 5, a shaft sleeve 6, a rotating shaft 7, a propeller 8, a conductive slip ring 9, an acceleration sensor 10, a fairing cap 11, a power amplifier 12, a signal generator 13, a data processing computer 15, a cable 16 and a guide rail 18, which are described in detail as follows.

The open water tank 1 is internally provided with a motor 3, a torque thrust and rotating speed testing system 4 and an electromagnetic exciter 5. The motor 3 is used to provide the rotational speed and torque of the propeller rotation. The torque thrust rotational speed test system 4 is used to measure the rotational speed, thrust and torque of the propeller rotation. The electromagnetic exciter 5 is used to excite the propeller to vibrate longitudinally, providing its longitudinal vibration frequency and amplitude. The electromagnetic exciter 5 is connected in communication with a power amplifier 12 and a signal generator 13 for exciting the propeller-shaft system to vibrate according to the desired signal.

One end of the rotating shaft 7 penetrates through the wall surface of the open water tank 1 and is arranged in the open water tank 1, the motor 3 is arranged at the end part of the rotating shaft 7, and the torque thrust and rotating speed testing system 4 and the electromagnetic exciter 5 are arranged in the rotating shaft 7. A shaft sleeve 6 is fixed on the open water tank, the rotating shaft 7 penetrates through the shaft sleeve 6, and the shaft sleeve 6 is used for supporting the rotating shaft 7.

The propeller 8 is arranged at the other end of the rotating shaft 7, acceleration sensors 10 are arranged on blades of the propeller 8 and the rotating shaft 7, the acceleration sensors 10 are output to a data processing computer 15 through a conductive slip ring 9 at the end part of the rotating shaft 7, and the acceleration sensors 10 are used for measuring vibration signals of the elastic propeller-shaft system.

The acceleration sensors 10 arranged on the blades are plural, and the plural acceleration sensors 10 are preferably uniformly arranged on the blades of the propeller 8. The distance between the position of the acceleration sensor 10 arranged on the blade and the axis of the propeller 8 is preferably 0.6-0.9 r, wherein r is the radius of the blade.

As shown in fig. 4 and 5, the conductive slip ring 9 includes a stator 19 and a rotor 20, which are arranged next to each other, the rotor 20 is connected to the acceleration sensor 10 through a cable 16, and the stator 19 is connected to the data processing computer 15 through the cable 16. Since the acceleration sensor 10 disposed on the blade rotates with the propeller, the signal of the rotating cable 16 needs to be transmitted to the stator 19 of the conductive slip ring 9 by means of the conductive slip ring 9, and then input to the data acquisition instrument 14 to complete the signal acquisition. Therefore, the conductive slip ring 9 is used for collecting vibration signals of the rotary propeller, and the signal collection difficulty caused by the rotation of the propeller can be overcome. Waterproof silica gel is uniformly distributed on the outer surfaces of the acceleration sensor 10 and the cable 16, so that normal work can be guaranteed under water.

The end part of the propeller 8 is provided with a fairing cap 11.

In order to avoid the influence of the wake flow at the rear part of the open water tank 1 on the water flow at the propeller in the advancing process, the distance between the propeller 8 and the open water tank 1 is more than 3 times of the diameter of the propeller 8.

The trailer 2 moves in cooperation with a guide rail 18 in a water pool 17, and the open water tank 1 is arranged on the trailer 2.

In a ship towing tank, a signal generator 13 sends out a hammering pulse/periodic excitation signal to excite an elastic paddle-shaft system to generate vibration, the technical difficulty of winding a cable 16 due to rotation of the paddle-shaft system is overcome based on a conductive slip ring 9, an acceleration sensor 10 is connected to a data acquisition instrument 14 through the conductive slip ring, and acceleration signals of points of interest on a propeller 8 and a rotating shaft 7 are measured. In the test, the influence law of wet modes and hydrodynamic damping parameters of the elastic paddle-shaft system in a static state and different sailing states is measured to represent the water elasticity characteristic of the elastic paddle-shaft system.

The test method adopting the underwater rotating propeller-shaft system water elasticity performance test device comprises the following steps:

s1: tests were conducted at different water depths and offshore distances, establishing ranges of water depths and offshore distances that can be approximated as infinite waters. So as to eliminate the influence of the wall surface and water surface effect on the test result.

S2: and for the wet modal characteristic, loading a periodic frequency sweep signal stronger than the excitation of the motor by an exciter to obtain the frequency response function of each acceleration at the paddle and the rotating shaft, and identifying the wet modal frequency and the modal shape of the paddle-shaft system under different working conditions by peak characteristics and phase relations.

S3: and determining the damping in a static state, wherein the motor does not rotate, applying a pulse signal through an electromagnetic exciter, and obtaining mechanical damping and viscous damping factors based on a free vibration attenuation method.

S4: and acquiring a damping factor in a motion state, dragging the trailer, rotating the motor, and applying a pulse signal which is far stronger than the excitation of the motor within the intensity range to obtain a total damping factor including hydrodynamic damping.

S5: and (5) subtracting the static damping obtained in the step S3 from the motion damping obtained in the step S4 to obtain the hydrodynamic damping, so as to obtain the change rule of the hydrodynamic damping along with the parameters.

In conclusion, the utility model provides the underwater rotating propeller-shaft system water elasticity performance test device, the limit of the traditional propeller size is avoided, the test device which is more consistent with the actual propeller running state is designed, and the accurate test of the water elasticity performance of the propeller-shaft system can be realized by installing the sensor and the vibration exciter in a matching way.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the utility model, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. An underwater rotating propeller-shaft system hydro-elastic performance test device, characterized in that the device comprises:

the device comprises an open water tank (1), wherein a motor (3), a torque thrust rotating speed testing system (4) and an electromagnetic exciter (5) are arranged in the open water tank (1);

the torque thrust and rotating speed testing system comprises a rotating shaft (7), wherein one end of the rotating shaft (7) penetrates through the wall surface of the open water tank (1) and is arranged in the open water tank (1), a motor (3) is arranged at the end part of the rotating shaft (7), the torque thrust and rotating speed testing system (4) and an electromagnetic exciter (5) are arranged in the rotating shaft (7), and the electromagnetic exciter (5) is in communication connection with a power amplifier (12) and a signal generator (13);

the propeller (8) is arranged at the other end of the rotating shaft (7), the blades of the propeller (8) and the rotating shaft (7) are provided with acceleration sensors (10), and the acceleration sensors (10) are output to a data processing computer (15) through conductive slip rings (9) at the end parts of the rotating shaft (7);

the trailer (2) moves in a matching way with a guide rail (18) in a water pool, and the open water tank (1) is arranged on the trailer (2).

2. The underwater rotating propeller-shaft system water elasticity performance test device according to claim 1, wherein the conductive slip ring (9) comprises a stator (19) and a rotor (20) which are arranged next to each other, the rotor (20) is connected with the acceleration sensor (10) through a cable (16), and the stator (19) is connected with the data acquisition instrument (14) through the cable (16) and further connected with the data processing computer (15).

3. The underwater rotating propeller-shaft system hydro-elastic performance test device of claim 1, characterized in that a plurality of acceleration sensors (10) are arranged on the blades, and the plurality of acceleration sensors (10) are uniformly arranged on the blades of the propeller (8).

4. The underwater rotating propeller-shaft system hydro-elastic performance test device according to claim 3, wherein the acceleration sensor (10) is arranged on the blade at a distance of 0.6-0.9 r from the axis of the propeller (8), wherein r is the radius of the blade.

5. The underwater rotating propeller-shaft system hydro-elastic performance test device of claim 1, characterized in that the distance between the propeller (8) and the open tank (1) is more than 3 times the diameter of the propeller (8).

6. The underwater rotating propeller-shaft system water elasticity performance test device according to claim 1, characterized in that a shaft sleeve (6) is fixed on the open water tank (1), and the rotating shaft (7) penetrates through the shaft sleeve (6).

7. The underwater rotating propeller-shaft system hydro-elastic performance test device of claim 1, characterized in that the end of the propeller (8) is provided with a fairing cap (11).