CN-115541179-B - Resistance-reducing structure surface fluid resistance testing device based on Tesla valve principle

CN115541179BCN 115541179 BCN115541179 BCN 115541179BCN-115541179-B

Abstract

The invention provides a resistance-reducing structure surface fluid resistance testing device based on a Tesla valve principle, which is used for experimental study on resistance-reducing performance of a resistance-reducing structure. The device comprises a frame, an outer cylinder, a Tesla valve flow limiting device, a rotor, a transmission device, a motor connecting frame and a motor, wherein the outer cylinder is fixed on the upper surface of the frame, the Tesla valve flow limiting device is fixed on the inner surface of the outer cylinder, the rotor is rotatably arranged at the central position inside the outer cylinder and is connected with the motor through the transmission device, and the motor is fixed on the lower surface of the frame through the motor connecting frame. The invention provides a fluid resistance testing device based on the characteristic that liquid reversely flows in a Tesla valve flow limiting device and has high damping, which can provide relatively stable and static flow field conditions for test samples laid on a rotor, and can also avoid the phenomenon that the flow field generates serious concave in a middle area and splashes due to rising of the liquid level in a peripheral area under the action of centrifugal force of the rotor, thereby accurately evaluating the drag reduction performance of the test samples.

Inventors

ZHAO DAN
GUO HONG
CUI JIN
LIU SHAOGANG
ZHAO YIFEI
GUO CHANG
DONG LIQIANG
TANG SHUAI
WU QIONG
GUO QIANG

Assignees

哈尔滨工程大学

Dates

Publication Date: 20260512
Application Date: 20220902

Claims (3)

1. The resistance-reducing structure surface fluid resistance testing device based on the Tesla valve principle is characterized by comprising a frame, an outer cylinder, a Tesla valve flow limiting device, a rotor, a transmission device, a motor connecting frame and a motor, wherein a boss with a central through hole is arranged at the central position of the inner bottom surface of the outer cylinder, the outer cylinder is fixed at the central position of the upper surface of the frame, the Tesla valve flow limiting device is coaxially fixed on the inner surface of the outer cylinder, the rotor is rotatably arranged at the central position of the inner part of the outer cylinder and is connected with the motor through the transmission device, and the motor is fixed on the lower surface of the frame through the motor connecting frame; The Tesla valve flow limiting device comprises an annular cover plate and a plurality of Tesla valve units, wherein the annular cover plate is fixedly connected with the inner surface of the outer cylinder, the Tesla valve units are uniformly fixed on the lower surface of the Tesla valve units around the central axis of the annular cover plate, the Tesla valve units comprise an inner side flow limiting plate, an outer side flow limiting plate and a connecting plate, the upper surface of the connecting plate is fixedly connected with the lower surface of the annular cover plate, and the openings of the inner side flow limiting plate and the outer side flow limiting plate face the same direction and are opposite to the rotating direction of the rotor, and are coaxially fixed on the lower surface of the connecting plate.
2. The tesla valve principle-based resistance reducing structure surface fluid resistance testing device according to claim 1, wherein the transmission device comprises a flange plate, a connecting shaft, a shaft coupling and a polytetrafluoroethylene pad, the flange plate is coaxially and rotatably fixed on the upper surface of a boss of the outer cylinder through the polytetrafluoroethylene pad, two ends of the connecting shaft are respectively connected with the flange plate and one end of the shaft coupling, the other end of the shaft coupling is connected with an output shaft of the motor, and the flange plate, the connecting shaft, the shaft coupling and the output shaft of the motor synchronously rotate.
3. The tesla valve principle-based drag reduction structure surface fluid resistance testing device is characterized in that the rotor is of a central symmetrical structure and comprises a connecting disc, two fan-shaped connecting plates, two arc-shaped connecting plates, a connecting beam, two supporting rib plates, two test piece mounting plates and two arc-shaped guide covers, wherein the lower surface of the connecting disc is coaxially fixed on the upper surface of the flange plate, one end of each fan-shaped connecting plate is symmetrically fixed on the upper surface of the connecting disc, the other end of each fan-shaped connecting plate is respectively connected with the lower ends of the two arc-shaped connecting plates, the upper ends of each arc-shaped connecting plate are respectively fixedly connected with the two ends of the connecting beam, one end of each supporting rib plate is respectively fixedly connected with the connecting disc, the other end of each supporting rib plate is respectively fixedly connected with the two ends of the connecting beam, the two test piece mounting plates are respectively fixedly connected with the two arc-shaped connecting plates, and the two arc-shaped guide covers are respectively fixed on the upstream ends of the two test piece mounting plates.

Description

Resistance-reducing structure surface fluid resistance testing device based on Tesla valve principle Technical Field The invention relates to a fluid resistance testing device, in particular to a resistance reducing structure surface fluid resistance testing device based on a Tesla valve principle. Background Turbulent flow drag reduction is always a hot spot problem of interest of researchers, and has very important significance in saving energy and improving maneuvering performance of ships. At present, related scholars propose adopting a flexible coating, a groove structure, a super-hydrophobic surface and other drag reduction structures to reduce the fluid resistance of an object, and verify the proposed drag reduction method through means of theoretical analysis, numerical simulation and model test. The construction of a corresponding testing device for testing the proposed drag reduction structure is the closest approach to the actual research means, and is an essential important work in the research process. The testing device adopted at present mainly comprises a wind tunnel, a water tunnel, a towing tank and the like, and the testing device can provide flow field conditions close to actual working conditions, but has large occupied area, high manufacturing cost and high testing cost, and has high requirements on testing environment, so that great inconvenience is brought to a fluid resistance testing test of a drag reduction structure. Therefore, it is important to design a small fluid resistance testing device which meets the test requirements and is low in cost for the research of the resistance reducing structure. The existing small-sized fluid resistance testing device is characterized in that a resistance reducing structure is laid on the surface of a disc or a cylindrical rotor, and a motor is utilized to drive the rotor to rotate in fluid so as to test the resistance reducing performance of the resistance reducing structure. However, since the rotor inevitably generates centrifugal force in the rotation process, the phenomenon of middle area sinking and liquid splashing occurs in the test flow field, and the whole flow field always flows along with the rotation of the rotor, a relatively stable and static flow field environment cannot be provided for the drag reduction structure, and thus, the test result is inaccurate. Disclosure of Invention The invention aims to provide a resistance reducing structure surface fluid resistance testing device based on a Tesla valve principle, which is used for experimental research on the proposed resistance reducing structure. The invention aims to achieve the purpose by the device, and the device comprises a frame, an outer cylinder, a Tesla valve flow limiting device, a rotor, a transmission device, a motor connecting frame and a motor. The inner bottom surface central position of the outer cylinder is provided with a boss with a central through hole, the outer cylinder is fixed at the central position of the upper surface of the frame, the Tesla valve flow limiting device is coaxially fixed at the inner surface of the outer cylinder, the rotor is coaxially and rotatably arranged at the inner central position of the outer cylinder and is connected with the motor through the transmission device, and the motor is fixed at the lower surface of the frame through the motor connecting frame. Preferably, the frame is made of Q235 steel and comprises a square support plate with rounded corners and four legs. The Tesla valve flow limiting device is made of stainless steel materials and comprises an annular cover plate and nine Tesla valve units. The annular cover plate is fixedly connected with the inner surface of the outer cylinder, and the nine Tesla valve units are uniformly fixed on the lower surface of the annular cover plate around the central axis of the annular cover plate. The tesla valve unit includes an inner restrictor plate, an outer restrictor plate, and a connecting plate. The upper surface of the connecting plate is fixedly connected with the lower surface of the annular cover plate, and the openings of the inner and outer side current limiting plates face the same direction and are opposite to the rotating direction of the rotor, and are coaxially fixed on the lower surface of the connecting plate. Preferably, the transmission device comprises a flange plate, a connecting shaft, a coupling and a polytetrafluoroethylene pad. The flange plate is made of 45 steel, a through hole is formed in the center of the flange plate, the flange plate is coaxially and rotatably fixed on the upper surface of the boss of the outer cylinder through the polytetrafluoroethylene pad, the connecting shaft is made of 45 steel, two ends of the connecting shaft are respectively connected with the flange plate and one end of the coupler, the other end of the coupler is connected with an output shaft of the motor, and the flange plate, the polytetrafluoroethylene pad and