The invention relates to an active liquid tank oscillation simulation test device which comprises a computer, a liquid tank oscillation component, a resistance-type wave height meter as well as a signal collecting processor, wherein the computer is connected with the liquid tank oscillation component fixedly connected with a liquid tank; and the resistance-type wave height meter is arranged in the liquid tank and is connected with the computer through the signal collecting processor. Compared with the prior art, according to the invention, the amplitude value and the cycle of the reciprocating motion of the liquid tank can be set randomly within certain amplitude value and certain frequency range, and the free surface real-time data of liquid oscillation in the tank can be measured under the motion excitation, so that the influences of ship body motion to the oscillation of the liquid tank are understood, and additionally the stepless transmission can be realized, and the test accuracy is improved.

Active liquid tank oscillation simulation test device

The invention discloses a novel water surface aircraft water load testing device. The novel water surface aircraft water load testing device comprises a water surface aircraft water load testing device body, wherein the water surface aircraft water load testing device body comprises a supporting connection beam (3), a front and rear supporting connection assembly, a lifting mechanism, a left and right supporting connection assembly and a group of linear bearing guide mechanisms; the supporting connection beam (3) is arranged in the middle of two box girders of a central testing bridge (1); and the front and rear supporting connection assembly is composed of a front supporting connection rod (30), a front supporting base (4), a front supporting threaded handle (3), a rear supporting connection rod (6) and a rear supporting threaded handle (7). According to the novel water surface aircraft water load testing device, lifting systems are capable of dual lifting, and are simple in installation and disassembly; the novel water surface aircraft water load testing device can realize 6 degree-of-freedom non-interference water touching and sliding, and is capable of more realistic simulation; linear bearings are adopted for vertical guidance, thereby improving the precision of vertical guidance; and the pitching and rolling gestures of a test piece are simple to adjust, and the test piece is easy to operate.

Novel water surface aircraft water load testing device

Multipurpose Towing Carridge with which Resistance and Propulsion Test and Maneuverability Test can be performed

This invention provides improvements in the efficiency of a sailing vessel throught the use of flaps, hydrofoils, or members on the keel of a sailing vessel. One or more are positioned at the top, or root of the keel of the vessel, which primarily generate a force in the windward direction to provide a counter-leeward drift force. One or more are located at the bottom, or tip of the keel of the vessel, which primarily generate a force in the leeward direction to provide a counter-heeling moment. Among other benefits, operation of these flaps, hydrofoils, or members during sailing increases the vessel's efficiency, in particular it's velocity made good. Further, since they are mounted on one appendage, sailing vessels of a rudder and keel design can be equipped with counter leeward-drift and counter-heeling attributes without the need for additional appendages.

Apparatus and method to optimize sailing efficiency

The invention discloses a ship model pitching, heaving and coupling motion remote test system. The system comprises a pool and a ship model positioned in the pool. A load iron block is installed at the center of gravity of the ship model, laser rangefinders are installed on the both sides of the load iron block, the laser rangefinders are connected with a data transmission station transmitting terminal, the data transmission station transmitting terminal is connected with a data transmission station receiving terminal through signals, the data transmission station receiving terminal is connected with a computer, the computer is connected with a client through a remote control module, a camera is arranged above the laser rangefinders, and the camera is connected with the data transmission station transmitting terminal through signals. According to the ship model pitching, heaving and coupling motion remote test system and a test method, the trim angle and heaving distance of a ship are measured by the devices of the laser rangefinders, the laser wavelength is short, the measurement error is very small, the influence from the surrounding environment is avoided, and the defect that greater errors are produced due to the fact that the traditional tilt angle sensors are easily affected by the surrounding environment is overcome.

Ship model pitching, heaving and coupling motion remote test system and test method

Draft measurement device of model ship in towing tank

The purpose of the present invention is to provide a device which can, with respect to performance evaluation of a ship in waves by means of a model test, reduce the component of primary wave power in the total resistance in waves and measure the total resistance in waves by means of a dynamometer that has appropriate capacity, and thus can consequently have improved measurement accuracy of additional resistance in waves. In order to attain the purpose, the present invention provides a device for measuring added resistance in waves, the device comprising: a moving unit which is disposed on a towing carriage, is connected to a model ship by means of a connecting rod, and moves forward and backward according to the forward and backward oscillation of the model ship; a restraining unit which is provided on the moving unit and partially restrains the movement of the moving unit; and a dynamometer which is provided on the connecting rod and measures the total resistance in waves applied to the model ship.

Device for measuring added resistance in waves

A method for effectively measuring added resistance in waves according to the present invention comprises: a moving unit disposed on an electric tug vehicle and connected to a model boat with a connection bar to move in a front/rear direction according to a front/rear movement of the model boat; a restraining unit provided with a first spring installed between the electric tug vehicle and a front end of the moving unit and a second spring installed between the electric tug vehicle and a rear end of the moving unit to partially restrain a movement of the moving unit; and a dynamometer installed on the connection bar to measure total resistance in waves imposed on the model boat. Let k be the sum of the spring constants of the first spring and the second spring. Let m′ be the sum of the mass of the model boat and an added mass in the front/rear direction. Let ωe be the angle of encounter frequency of the model ship. Then k is determined to satisfy the relationship k << m′ωe^2 to allow the dynamometer to eliminate a primary wave power and measure a time average of total resistance in waves. According to the present invention, since total resistance in waves can be measured with a dynamometer of an adequate capacity when evaluating ship performance in waves through a model test, precision of measurement of added resistance in waves can be improved.

Method for measuring added resistance in waves

The present invention relates to a method for setting a draught condition of a model ship by using an automatic model ship draught control device including a draught measuring device, a wireless transmitting and receiving device, and a gravity center shifting device which are provided on the inside of the model ship, and a wireless control device which is provided on the outside of the model ship to carry out wireless communications with the wireless transmitting and receiving device The present invention provides a method for setting a draught condition of a model ship through the automatic reciprocating motion of a weight, comprising: a step where the draught measuring device measures the draught of the model ship and transmits the measured draught value to the wireless transmitting and receiving device; a step where the wireless transmitting and receiving device transmits the measured draught value of the draught measuring device to the wireless control device; a step where the wireless control device generates a gravity center shifting command if the measured draught value of the draught measuring device is different from a pre-calculated set draught value; a step where the wireless transmitting and receiving device receives the gravity center shifting command of the wireless control device and transmits the same to the gravity center shifting device; and a step where the gravity center shifting device automatically shifts the gravity center position of the model ship through the linear reciprocating motion of the weight

Device for automatic draught setting of model ship

The purpose of the present invention is to provide a device which can enable quick and accurate setting of a draft condition of a model ship by means of an automated system without manually changing the position of a weight during a model test. In order to attain the purpose, the present invention provides an automatic draft adjustment device for a model ship, the automatic draft adjustment device comprising: a draft measurement apparatus which is provided on a model ship, measures the draft of the model ship, and transmits a measured draft value to a wireless transmission and reception apparatus; the wireless transmission and reception apparatus which is provided on the model ship, communicates wirelessly with a wireless adjustment apparatus, transmits the measured draft value from the draft measurement apparatus to the wireless adjustment apparatus, receives a gravity center changing command from the wireless adjustment apparatus, and transmits same to a gravity center changing apparatus; the wireless adjustment apparatus which is provided on the outside of the model ship and, if the measured draft value from the draft measurement apparatus is different from a pre-calculated set draft value, generates a gravity center changing command; and the gravity center changing apparatus which is provided on the model ship and, if the wireless adjustment apparatus generates the gravity center changing command, automatically changes the position of the gravity center of the model ship by means of the linear reciprocating motion of a weight.

Ahn Hae Seong

Papers

Draft measurement device of model ship in towing tank

Device for measuring added resistance in waves

Method for measuring added resistance in waves

Device for automatic draught setting of model ship

Automatic draft adjustment device for model ship