Measuring Mechanism in Ship Model Rotary Arm Test

Abstract

A measurement mechanism in ship model spiral arm tests comprises a middle seat fixedly connected with a trailer, heaving rods penetrate through the middle seat and can vertically slide, the lower ends of the heaving rods are fixedly connected with a bottom board, the bottom board is provided with a linear displacement sensor, the upper end of the bottom board is connected with a steel wire rope, the other end of the steel wire rope winds around a pulley and then is connected with a balance weight lever, the balance weight lever slides in a guide seat and is provided with a balance weight, the lower end of the bottom board is fixedly connected with a four-component force transducer through a connection rod, the four-component force transducer is fixedly connected with a longitudinally rocking seat which is provided with longitudinally rocking shafts in a rotary mode, the longitudinally rocking shafts are connected with a rotary potentiometer and are fixedly provided with a middle frame, the two ends of the middle frame are fixedly connected with transversely rocking fixed seats which are provided with transversely rocking angle scales, and the lower ends of the transversely rocking fixed seats are fixedly connected with a model base connected with a ship model. The measurement mechanism can measure the longitudinal dip angle and heaving displacement of the ship model and water power in the four movement directions including the longitudinal direction, the transverse direction, the transversely rocking direction and the yawing direction of the ship model.

Description

technical field [0001] The invention relates to the technical field of constrained ship model tests, in particular to a ship model swing arm test used to measure the hydrodynamic characteristics of a ship model in circular motion, in particular to a swing arm test connected between a swing arm trailer and a ship model Measuring mechanism for measuring the heave displacement of the ship model, the change of trim attitude, and the hydrodynamic force of the ship model in four directions of motion (including longitudinal, lateral, roll, and yaw) during the slewing process. Background technique [0002] Constraint model test is currently the most widely used method to obtain the hydrodynamic derivative of a ship, that is, to use mechanical constraints to force the ship model to perform specified motions, such as linear motion, rotary motion, etc. During the model test, by systematically changing the Motion parameters, measuring the hydrodynamic force acting on the ship model, so ...

AI Technical Summary

Problems solved by technology

In addition to the normal movement of the ship model with the yaw angle, the ship model cantilever test when sailing with a high Froude number also requires the ship model to be able to move freely in the vertical and pitch directions, and at the same time to be able to perform variable heel hydrodynamic forces. At present, there is no measuring device for the maneuverability arm test of the ship model, and due to the limited installation conditions of the internal control of the ship model and the arm tank, it is necessary that the arm test measuring device is not too large, which increases the size of the arm. Difficulty in designing test and measurement devices

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