CN113008510B - Closed water tunnel and open water tank comprehensive test device - Google Patents
Closed water tunnel and open water tank comprehensive test device Download PDFInfo
- Publication number
- CN113008510B CN113008510B CN202110081195.7A CN202110081195A CN113008510B CN 113008510 B CN113008510 B CN 113008510B CN 202110081195 A CN202110081195 A CN 202110081195A CN 113008510 B CN113008510 B CN 113008510B
- Authority
- CN
- China
- Prior art keywords
- section
- loop
- water tunnel
- water tank
- open
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M10/00—Hydrodynamic testing; Arrangements in or on ship-testing tanks or water tunnels
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
Landscapes
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Physics & Mathematics (AREA)
- Aerodynamic Tests, Hydrodynamic Tests, Wind Tunnels, And Water Tanks (AREA)
Abstract
The invention provides a closed water tunnel and open water tank comprehensive test device, which comprises a closed water tunnel loop, a driving motor, a pressure regulating device, a sound measuring cabin and an open water tank loop, wherein the closed water tunnel loop is connected with the driving motor; the closed water tunnel loop comprises a steady flow section, a contraction section, a test section, an upper diffusion section, a first corner section, a first transition section, a second corner section, a second transition section, a driving pump, a lower diffusion section, a third transition section, a third corner section, a fourth transition section and a fourth corner section which are sequentially connected to form the loop, and the sound measuring cabin is arranged below the test section; open basin return circuit is including setting up the supplementary return circuit in the outside between last diffusion section and first changeover portion, and the upper cover plate has been arranged to the test section top, forms open return circuit when the upper cover plate of test section top is uncovered. A sounding cabin or a sounding cavity can be arranged below the test section for testing the underwater radiation noise of the tested model, so that the comprehensive testing capability of hydrodynamic force, cavitation and noise is improved, and the comprehensive construction cost is obviously reduced.
Description
Technical Field
The invention belongs to the field of hydrodynamics and ship tests, and particularly relates to a closed water tunnel and open water tank comprehensive test device.
Background
The device for carrying out hydrodynamic performance tests of ships, navigation bodies, propellers and the like mainly comprises a towing tank, a circulating water tank and a cavity water tunnel. Due to the fact that the length of the track of the towing tank is limited, the test time is limited by the running time of the frame, and the observation test of cavitation bubbles and a flow field is inconvenient to carry out. The circulating water tank and the cavitation water hole can make water flow circularly in the circulating water tank and the cavitation water hole by using the flow making system, and a model arranged in a test section can be tested for a long time without being limited by time, so that flow field parameters can be conveniently measured, and cavitation and flow field observation tests can be conveniently carried out. And a sound measuring cabin or a sound measuring cavity is arranged below the test section of the circulating water tank and the cavity water hole, so that the noise of the model can be measured. The test section of the circulating water tank is open, has free liquid level and can not be pressurized or depressurized; the cavitation water tunnel is usually provided with a pressure regulating device, and simulation of different water depths and cavitation numbers can be realized through pressure increasing and reducing.
Because the structural similarity of circulating water tank and cavity water cavity, from the theory, cavity water cavity and circulating water tank can design into integral type combined test device.
The patent application with the application number of 201811565809.3 discloses a water tunnel and water tank dual-purpose experiment system, which comprises a water tunnel experiment section, a water pump system, a preposed water tank, a water tank experiment section and a postpositive water tank, wherein the preposed water tank, the water tank experiment section and the postpositive water tank are sequentially communicated; the experimental system is arranged in a vertical upper layer and a vertical lower layer, the two water tanks and the experimental section of the water tank are both positioned on the upper layer, the tops of the upper layer structure and the upper layer structure are both open, the water pump system is positioned on the lower layer, and the lower layer structure is a closed pipeline; the front vertical section between the upper layer and the lower layer is a pipeline transition section, the rear vertical section is a water tunnel experiment section, a bottom water inlet of the front water tank is communicated with a water outlet of the water pump system through the pipeline transition section, and a bottom water outlet of the rear water tank is communicated with a water inlet of the water pump system through the water tunnel experiment section. The device realizes two purposes of a water tunnel and a water tank, but the device does not have a pressure adding and reducing device, can not adjust the pressure range in the water tunnel, and has limited measurable working conditions; and the water tunnel test section is in the vertical section, so that the installation of the tested model is inconvenient, and particularly, the test preparation time is very long along with the increase of the scale of the test system.
Patent application No. 201910056910.4 discloses a multi-functional powered circulation tank, includes: a flow circulation pipeline, a power device and a control system; wherein, the flow circulation pipeline comprises a water storage tank, a return pipe, a return water tank and a water tank; the power device and the control system are arranged on the motor bracket, and the power device drives fluid to flow into the water storage tank from the return water tank through the water tank and flow into the return water tank from the water storage tank through the return pipe, so as to form circulation; the power plant regulates the flow rate of the fluid under the control of the control system. The device has low flow rate (less than or equal to 0.5 m/s) and does not have the function of a cavity water hole.
In view of this, a comprehensive test device combining a closed water tunnel and an open water tank is needed to be designed, so that the test problems of hydrodynamic force, cavitation, noise and the like of objects such as underwater vehicles, water surface different aircrafts, thrusters and the like are solved, the comprehensive construction cost is reduced, the construction and use efficiency of the device is improved, and more comprehensive benefits are brought into play.
Disclosure of Invention
The invention aims to provide a closed water tunnel and open water tank comprehensive test device with good flow field quality, which is used for carrying out hydrodynamic tests, cavitation tests, flow field observation tests and noise tests of models such as underwater and water surface navigation bodies, propellers and the like.
In order to achieve the purpose, the invention designs a closed water tunnel and open water tank comprehensive test device, which comprises a closed water tunnel loop, a driving motor arranged outside the closed water tunnel loop, a pressure regulating device and a sound measuring cabin which are connected with the closed water tunnel loop through pipelines, and an open water tank loop; the closed water tunnel loop comprises a steady flow section, a contraction section, a test section, an upper diffusion section, a first corner section, a first transition section, a second corner section, a second transition section, a driving pump, a lower diffusion section, a third transition section, a third corner section, a fourth transition section and a fourth corner section which are sequentially connected to form the loop, and the sound measuring cabin is arranged below the test section; the open type water tank loop comprises an auxiliary loop arranged on the outer side between the upper diffusion section and the first transition section, an upper cover plate is arranged above the test section, and an open type loop is formed when the upper cover plate above the test section is uncovered.
Furthermore, the auxiliary loop, the upper diffusion section and the first transition section are separated by a partition plate, the partition plate above the upper diffusion section is a floating device, a gas collection box is arranged above the auxiliary loop above the first corner section, and air in the gas collection box is discharged through a gas discharge pipeline by using an air exhaust device; and water in the auxiliary loop is pumped back to the closed water tunnel loop through the first transition pipeline, the auxiliary pump and the second transition pipeline.
Furthermore, a water tunnel transition section is arranged above the upper diffusion section and close to the position of the test section, the upper plane of the water tunnel transition section is flush and butted with the upper plane of the auxiliary loop, and the lower plane of the upper cover plate is smoothly and seamlessly connected with the upper overflow surface of the contraction section, the lower overflow surface of the bottom plate of the water tunnel transition section and the lower overflow surface of the partition plate, so that the water tunnel forms a closed loop.
Furthermore, a water tank transition section without a bottom plate is arranged on the upper diffusion section close to the test section, and an open loop is formed when an upper cover plate above the upper test section is uncovered.
Furthermore, observation windows composed of glass with good light transmittance are arranged on the side walls of the two sides of the test section.
Furthermore, the bottom plate of the test section is provided with sound-transmitting glass to separate the test section from the sound measuring cabin.
Furthermore, the driving motor is arranged outside the closed water tunnel loop and connected with a driving shaft of the driving pump through an elastic coupling.
Further, the driving pump is located at the downstream of the second corner section, and the second transition section is a square and round transition section.
Further, the driving pump is located at the lowest position of the closed water tunnel loop.
By adopting the technical scheme, the invention has the following technical effects:
1. the closed water tunnel and open water tank comprehensive test device has a cavity water tunnel function, and can carry out tests such as hydrodynamic force and cavitation under different models such as an underwater vehicle and a propeller and under different water depth and cavitation number conditions;
2. the closed water tunnel and open water tank comprehensive test device has the function of a circulating water tank with a free liquid level, and can perform tests such as hydrodynamic force, cavitation and the like under different Froude number conditions and different models such as a water surface aircraft, a propeller and the like;
3. the closed water tunnel and open water tank comprehensive test device can arrange the sound measuring cabin or the sound measuring cavity below the test section, is used for testing the underwater radiation noise of the tested model, improves the comprehensive testing capability of hydrodynamic force, cavitation and noise, and obviously reduces the comprehensive construction cost.
Drawings
FIG. 1 is a schematic diagram of the general structure of a closed water tunnel and open water tank comprehensive test device according to the invention;
FIG. 2 is a schematic illustration of the experimental section of FIG. 1;
FIG. 3 is a schematic view of a transition section of the water tunnel of FIG. 1;
FIG. 4 is a schematic diagram of the auxiliary circuit and the transition section of the water tank in FIG. 1.
The parts in the drawings are numbered as follows:
100-closed water tunnel loop, 1-stable section, 2-second transition pipeline, 3-contraction section, 4-test section, 5-upper cover plate, 6-upper diffusion section, 7-first corner section, 8-first transition section, 9-second corner section, 10-second transition section, 11-driving pump, 12-lower diffusion section, 13-third transition section, 14-third corner section, 15-fourth transition section, 16-fourth corner section, 17-driving motor, 18-elastic coupling, 19-driving shaft, 20-pipeline, 21-pressure regulating device, 22-partition plate, 23-auxiliary loop, 24-gas collection box, 25-exhaust pipeline, 26-air extraction device, 27-auxiliary pump, 28-first transition pipeline, 30-sound measurement cabin, 41-observation window, 42-sound-transparent glass, 62-water tunnel transition section, 621-bottom plate, 63-water tank transition section and 200-water tank loop.
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 invention and do not limit the invention.
As shown in fig. 1, the closed water tunnel and open water tank comprehensive test device comprises a closed water tunnel loop 100, a driving motor 17 arranged outside the closed water tunnel loop 100, a pressure regulating device 21 connected with the closed water tunnel loop 100 through a pipeline 20 and a sound measuring cabin 30, wherein the pressure regulating device 21 is communicated with the inside of the closed water tunnel loop 100 through the pipeline 20 to pressurize or depressurize the inside of the closed water tunnel loop 100; the closed water tunnel loop 100 comprises a steady flow section 1, a contraction section 3, a test section 4, an upper diffusion section 6, a first corner section 7, a first transition section 8, a second corner section 9, a second transition section 10, a driving pump 11, a lower diffusion section 12, a third transition section 13, a third corner section 14, a fourth transition section 15 and a fourth corner section 16 which are sequentially connected to form a loop; the sounding chamber 30 is mounted below the test section 4.
In this embodiment, the driving motor 17 is disposed outside the closed water tunnel loop 100, and the driving motor 17 is connected to the driving shaft 19 of the driving pump 11 through the elastic coupling 18 to provide driving force for water flow. The driving pump 11 is located at the downstream of the second corner section 9, and in order to realize smooth transition between the square section outlet of the second corner section 9 and the round section inlet of the driving pump 11, the second transition section 10 arranged between the two is a square round transition section. In addition, the closed water tunnel loop 100 is in a vertical layout, and the driving pump 11 is located at the lowest position of the closed water tunnel loop 100, so that the purpose of inhibiting the cavitation of the driving pump 11 is achieved.
As shown in fig. 1 and 4, when operating as a water tank, the open water tank circuit 200 adds an auxiliary circuit 23 on the basis of the closed water tunnel circuit 100, the auxiliary circuit 23 is arranged outside the middle section between the upper diffuser section 6 and the first transition section 8 and is separated by a partition plate 22, and the partition plate 22 above the upper diffuser section 6 is a troweling device for dividing upstream incoming flow; and a gas collection box 24 is arranged above the auxiliary loop 23 above the first corner section 7 for collecting air brought by the free liquid level in the water flow above the trowelling device, and the air in the gas collection box 24 is exhausted through an exhaust pipeline 25 by using an air exhaust device 26. The water in the auxiliary circuit 23 is pumped back to the closed-circuit tunnel 100 via the first transition line 28, the auxiliary pump 27 and the second transition line 2, so that the load on the drive pump 11 is reduced and the auxiliary pump 27 is driven by an external motor.
As shown in fig. 1 to 3, when the water tunnel is operated, the upper cover plate 5 is arranged above the test section 4, meanwhile, the water tunnel transition section 62 is arranged above the upper diffusion section 6 and close to the test section 4, the upper plane of the water tunnel transition section 63 is flush and butt-jointed with the upper plane of the auxiliary loop 23, and the lower plane of the upper cover plate 5 is smoothly and seamlessly connected with the upper overflowing surface of the contraction section 3, the lower overflowing surface of the bottom plate 621 of the water tunnel transition section 62 and the lower overflowing surface of the partition plate 22, so that the water tunnel forms a closed loop.
Or the upper cover plate 5 above the test section 4 is uncovered, the atmosphere is introduced above the test section 4, the test section 4 has a free liquid level, and meanwhile, the water tunnel transition section 62 of the upper diffusion section 6 close to the test section 4 is replaced by a water tank transition section 63 without a bottom plate, so that the water tank forms an open loop. Similarly, the optical observation and flow display tests are performed by using the observation windows 41 on the two side walls of the test section 4, and the model noise measurement tests are performed by using the sounding chamber 30 below the test section 4.
In this embodiment, the observation windows 41 made of glass with good light transmittance are respectively installed on the two side walls of the test section 4, so as to optically observe the model in the test section 4 and develop the flow display test. A sound measuring cabin 30 is arranged below the test section 4 and used for carrying out a model noise measurement test; the floor of the test section 4 is fitted with acoustically transparent glass 42 separating the test section 4 from the sounding chamber 30.
Through elaborately designing each section, under the conditions that the contraction ratio is not less than 6 and the driving power is large enough, the flow velocity of the water tunnel test section exceeds 12m/s, and the flow field quality reaches the level that the flow velocity nonuniformity is less than 1% and the turbulence degree is less than 0.5%; by reasonably designing the pressure increasing and reducing device and the hole body structure, the pressure range of the test section can reach 4 kPa-400 kPa, and the water depth of 30m can be simulated; the flow velocity of the test section of the water tank exceeds 10m/s, the Froude number is more than 2, and the wave height and the levelness of the free liquid level are both well controlled to reach a higher level.
The closed water tunnel and open water tank comprehensive test device can not only meet hydrodynamic tests, cavitation tests, flow field observation tests and noise tests of models such as an underwater vehicle and a propeller at different depths and within a cavitation number range, but also realize the simulation of different Froude numbers of the models such as a water surface vehicle and the propeller; the device has wide application range, strong comprehensive testing capability and low comprehensive construction cost.
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 invention, 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 (7)
1. The utility model provides a closed water tunnel and open basin combined test device which characterized in that: the device comprises a closed water tunnel loop (100), a driving motor (17) arranged outside the closed water tunnel loop (100), a pressure regulating device (21) and a sound measuring cabin (30) which are connected with the closed water tunnel loop (100) through a pipeline (20), and an open water tank loop (200); the closed water tunnel loop (100) comprises a steady flow section (1), a contraction section (3), a test section (4), an upper diffusion section (6), a first corner section (7), a first transition section (8), a second corner section (9), a second transition section (10), a driving pump (11), a lower diffusion section (12), a third transition section (13), a third corner section (14), a fourth transition section (15) and a fourth corner section (16) which are sequentially connected to form the loop, and a sound measuring cabin (30) is arranged below the test section (4); the open type water tank loop (200) comprises an auxiliary loop (23) arranged on the outer side between the upper diffusion section (6) and the first transition section (8), an upper cover plate (5) is arranged above the test section (4), and the upper cover plate (5) above the test section (4) forms an open type loop when being uncovered;
the auxiliary loop (23) is separated from the upper diffusion section (6) and the first transition section (8) by a partition plate (22), the partition plate (22) above the upper diffusion section (6) is a floating device, a gas collection box (24) is arranged above the auxiliary loop (23) above the first corner section (7), and air in the gas collection box (24) is discharged through a gas discharge pipeline (25) by using an air extraction device (26); the water in the auxiliary loop (23) is pumped back to the closed water tunnel loop (100) through the first transition pipeline (28), the auxiliary pump (27) and the second transition pipeline (2); go up diffuser (6) top and be close to experimental section (4) position department and arranged water tunnel changeover portion (62), water tunnel changeover portion (62) upper flat and supplementary return circuit (23) upper flat parallel and level butt joint, the lower overflow surface of the lower plane of upper cover plate (5) and the last overflow surface of shrink section (3), the lower overflow surface of bottom plate (621) of water tunnel changeover portion (62) and the lower overflow surface smooth and seamless connection of baffle (22) make the water tunnel form closed return circuit.
2. The comprehensive test device for the closed water tunnel and the open water tank according to claim 1, characterized in that: the water tunnel transition section (62) is replaced by a water tank transition section (63) without a bottom plate, and an open loop is formed when the upper cover plate (5) above the test section (4) is uncovered.
3. The comprehensive test device for the closed water tunnel and the open water tank according to claim 1, characterized in that: and observation windows (41) consisting of glass with good light transmittance are arranged on the side walls of the two sides of the test section (4).
4. The comprehensive test device for the closed water tunnel and the open water tank according to claim 1, characterized in that: the bottom plate of the test section (4) is provided with sound-transmitting glass (42) to separate the test section (4) from the sound measuring cabin (30).
5. The comprehensive test device for the closed water tunnel and the open water tank according to claim 1, characterized in that: the driving motor (17) is arranged outside the closed water tunnel loop (100), and the driving motor (17) is connected with a driving shaft (19) of the driving pump (11) through an elastic coupling (18).
6. The comprehensive test device for the closed water tunnel and the open water tank according to claim 1, characterized in that: the driving pump (11) is positioned at the downstream of the second corner section (9), and the second transition section (10) is a square and round transition section.
7. The comprehensive test device for the closed water tunnel and the open water tank according to claim 1, characterized in that: the driving pump (11) is positioned at the lowest part of the closed water tunnel loop (100).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110081195.7A CN113008510B (en) | 2021-01-21 | 2021-01-21 | Closed water tunnel and open water tank comprehensive test device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110081195.7A CN113008510B (en) | 2021-01-21 | 2021-01-21 | Closed water tunnel and open water tank comprehensive test device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113008510A CN113008510A (en) | 2021-06-22 |
| CN113008510B true CN113008510B (en) | 2023-04-14 |
Family
ID=76384473
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110081195.7A Active CN113008510B (en) | 2021-01-21 | 2021-01-21 | Closed water tunnel and open water tank comprehensive test device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113008510B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH072952U (en) * | 1993-04-21 | 1995-01-17 | 日立造船株式会社 | Circulating water tank |
| JP2008014885A (en) * | 2006-07-10 | 2008-01-24 | Nishi Nippon Ryutai Giken:Kk | Water tunnel device |
| CN102680222A (en) * | 2012-05-14 | 2012-09-19 | 大连理工大学 | Blade experiment device for tidal current energy water turbine |
| CN105444986A (en) * | 2015-12-29 | 2016-03-30 | 国家海洋技术中心 | Multifunctional vertical circulating current-generating test facility |
| CN109781378A (en) * | 2018-12-20 | 2019-05-21 | 西安交通大学 | A kind of dual-purpose experimental system of water hole sink |
-
2021
- 2021-01-21 CN CN202110081195.7A patent/CN113008510B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH072952U (en) * | 1993-04-21 | 1995-01-17 | 日立造船株式会社 | Circulating water tank |
| JP2008014885A (en) * | 2006-07-10 | 2008-01-24 | Nishi Nippon Ryutai Giken:Kk | Water tunnel device |
| CN102680222A (en) * | 2012-05-14 | 2012-09-19 | 大连理工大学 | Blade experiment device for tidal current energy water turbine |
| CN105444986A (en) * | 2015-12-29 | 2016-03-30 | 国家海洋技术中心 | Multifunctional vertical circulating current-generating test facility |
| CN109781378A (en) * | 2018-12-20 | 2019-05-21 | 西安交通大学 | A kind of dual-purpose experimental system of water hole sink |
Non-Patent Citations (1)
| Title |
|---|
| 戴波等.原油管道内检测器速度控制试验装置的研制.自动化仪表.2016,第37卷(第11期),第69-76页. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113008510A (en) | 2021-06-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112798225B (en) | Vertical tandem double-test section cavitation water hole test device | |
| CN107300456B (en) | A kind of supercavity experimental rig and test method | |
| Atlar | Recent upgrading of marine testing facilities at Newcastle University | |
| Brandner et al. | Design considerations in the development of a modern cavitation tunnel | |
| Eslamdoost | The hydrodynamics of waterjet/hull interaction | |
| CN113008510B (en) | Closed water tunnel and open water tank comprehensive test device | |
| CN108791701B (en) | Ultra-large type floating body single module capable of being spliced quickly and assembly structure thereof | |
| CN203094366U (en) | Device for experimenting and testing tail rudder resistance of water spraying combination propeller body | |
| CN204726636U (en) | A kind of boats and ships with balancing device | |
| JP4230365B2 (en) | Air intake system for ships | |
| CN114735132B (en) | Vibration-damping noise-reducing liquid tank device on small-waterplane-area catamaran support column and using method thereof | |
| CN201520395U (en) | Bubble drag reduction subdivision variable-pressure air injection device | |
| CN106143846A (en) | A kind of small underwater binary sightseeing ship | |
| CN112829935A (en) | Water airship | |
| JPH1159563A (en) | Friction reducing ship and air generator | |
| CN110006627B (en) | Experimental observation device for simulating air cavity propagation under air cushion ship | |
| CN104812662B (en) | Ship | |
| JPS5945552B2 (en) | Experimental equipment for waterjet propulsion equipment | |
| JPH10175587A (en) | Frictional resistance reducing device for ship | |
| Kim et al. | Numerical and Experimental Evaluation of Waterjet Propelled Amphibious Tracked Vehicles | |
| RU2816429C2 (en) | High-speed small vessel on compressed pneumatic flow | |
| JP2001328584A (en) | Frictional resistance-reduced ship | |
| Etter | State of the art-cavitation test facilities and experimental methods | |
| JP5638374B2 (en) | Hull | |
| SU991226A1 (en) | Device for testing main power plants of a ship afloat |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |