Acquisition method of shooting and recording time in launch type wind tunnel free flight test

A technology for recording time and obtaining methods, which can be applied in aerodynamic tests, machine/structural component testing, and measuring devices, etc. It can solve problems such as ineffective identification of aerodynamic parameters, loss of test information, and shortened shooting and recording time. , to achieve accurate analysis and aerodynamic parameter identification accuracy guarantee and low cost effect

A technology for recording time and obtaining methods, which can be applied in aerodynamic tests, machine/structural component testing, and measuring devices, etc. It can solve problems such as ineffective identification of aerodynamic parameters, loss of test information, and shortened shooting and recording time. , to achieve accurate analysis and aerodynamic parameter identification accuracy guarantee and low cost effect

CN104458202BActive Publication Date: 2017-05-03CHINA ACAD OF AEROSPACE AERODYNAMICS

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  • Acquisition method of shooting and recording time in launch type wind tunnel free flight test
  • Acquisition method of shooting and recording time in launch type wind tunnel free flight test

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Embodiment Construction

[0021] In order to make the above objects, features and advantages of the present invention more comprehensible, specific implementations of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0022] see figure 1 , the present invention provides a method for obtaining shooting and recording time in a launching type wind tunnel free flight test, said method comprising the following steps:

[0023] (1) Obtain the trim angle α of the model T The drag coefficient C at D , wind tunnel flow field to flow pressure q ∞ , Wind tunnel observation window diameter L 1 , the model mass m and the reference area s of the model.

[0024] (2) Calculate the resistance value of the model in the process of free flight in the wind tunnel flow field as D=C D ·q ∞ s, then the acceleration value of the model in the process of free flight in the wind tunnel flow field is:

[0025] (3) Assume that the velocity V of the leading edge of the mo...

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Abstract

The invention discloses a method for obtaining shooting recording time in a launching type wind tunnel free flight test. The method includes the following step that it is assumed that the speed of a model is zero when the model arrives at the front edge of a wind tunnel observation window, and the launching initial velocity of the model is calculated through displacement and acceleration obtained from the launching position to the front edge of the wind tunnel observation window of the front edge of the model. According to the resistance coefficient of the test model, wind tunnel flow field parameters, the wind tunnel observation window size range and other parameters, the launching initial velocity, at which the longest effective shooting recording time of the test can be obtained, of the model can be estimated, and the situation that the launching initial velocity is repeatedly adjusted in a wind tunnel through a practical air blowing test to obtain the longest shooting recording time is not needed. According to the estimated launching initial velocity, the maximum angular motion cycle number of the model capable of being shot and recorded can be further estimated at the longest effective shooting recording time.

Description

technical field [0001] The invention relates to a method for acquiring shooting and recording time in a launch type wind tunnel free flight test, which can be applied to the launch type wind tunnel free flight test. Background technique [0002] Wind tunnel free flight test is an important method in the study of aircraft dynamic characteristics. Because there is no support interference, the flight state can be simulated more realistically, and the flight state of the model can be directly observed through high-speed photography, so the wind tunnel free flight test technology has shown unique advantages in the study of aircraft dynamic characteristics. The test principle is to truly reproduce the dynamic characteristics of the aircraft under the action of unsteady aerodynamic forces in the free flight state under the condition that the wind tunnel test is similar to the dynamics of the flight state, and can directly record and observe the motion characteristics of the aircraf...

Claims

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Application Information

Patent Timeline
03 May 2017
Publication
CN104458202B
IPC
G01M9/06
Inventors
蒋增辉; 宋威