System and method for measuring flow field of large ship surface in wind tunnel test

Abstract

The invention discloses a system and method for measuring a flow field of a large ship surface in a wind tunnel test. According to the system, the front surface of a stepping motor fixing frame is provided with a Hall element, and a motor rotating disc is fixedly provided with small magnetic steel. When a ship rolling and pitching system operates and the small magnetic steel is closest to the Hallelement, the Hall element obtains an electric signal and transmits the electric signal to a synchronizer, and the electric signal serves as a trigger signal for shooting of a particle image speed measurement system. The synchronizer controls a laser emitter to emit a laser beam, the laser beam irradiates a far reflector, the direction of the laser beam deflects, and a surface laser is obtained through a circular glass rod to illuminate a flow field cross section needing to be researched. Such a special light path gets rid of the size limitation of a laser generator and the space limitation brought by a wind tunnel structure, and meanwhile the influence of the laser emitter on a wind field is avoided. According to the measurement system and method, accurate positioning and phase-locked shooting can be carried out on the cross section of a ship model in a certain posture in a motion period, and the flow field characteristics of the ship surface are obtained.

Description

technical field [0001] The invention belongs to the technical field of wind tunnel tests, in particular to a system and method for measuring the surface flow field of large-scale sports ships in wind tunnel tests; Background technique [0002] my country has a vast territorial waters and a correspondingly long coastline, with a large north-south span and difficult coastal defense forces. Therefore, the development of aircraft carriers and amphibious assault ships is of great significance. The amphibious assault ship is mainly responsible for large-scale transportation, armed attack, armed landing and other tasks. Among them, the carrier-based aircraft of the amphibious assault ship, which uses the mothership deck as the take-off and landing platform, plays a key role in the execution of the mission as the vanguard and mobile force. However, due to the small deck space of the ship and the complicated sea conditions, the ship will experience a complicated shaking process, and ...

AI Technical Summary

Problems solved by technology

However, due to the small deck space of the ship and the complicated sea conditions, the ship will experience a complicated shaking process, and its unique take-off and landing environment will severely test the maneuverability of the carrier-based aircraft; the complex movement of the ship, the change of incoming flow and The complex buildings on the ship deck will make the ship deck flow field complex and dangerous, which will endanger the safety of the carrier-based aircraft when taking off and landing, so it is very important to carry out the study of the ship deck flow field

[0003] Although the research on the ship flow field has become more and more extensive in recent years, due to the particularity of the study on the ship flow field, most of the research stays in the numerical calculation, and for the ship's rolling and pitching motion at sea There are still relatively few studies on flow field changes.

At present, in the traditional ship model flow field measurement test, all static small ship models are used, which cannot realize the dynamic ship surface flow field measurement of large ships.

For the measurement of the dynamic ship surface flow field on large ships, many problems will be encountered, such as: due to the large size of the wind tunnel experiment section and the ship model, the particle image velocity measurement equipment cannot be built in the wind tunnel, and the external The laser control and generation device cannot be irradiated correctly due to the limitation of the light guide arm; when the large ship model is moving, the ship attitude angle and the particle image speed measurement shooting cannot be triggered synchronously, resulting in the captured data not corresponding to the ideal situation; in the wind tunnel test When the time is tight and the experimental tasks are heavy, reduce the number of experimental trains, complete the experiment and achieve the experimental purpose of flow field measurement; how to shoot the special attitude angle of the large dynamic ship model

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