CN202171525U

CN202171525U - Device for measuring coefficient of air resistance

Info

Publication number: CN202171525U
Application number: CN2011202531971U
Authority: CN
Inventors: 严九洲
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-07-18
Filing date: 2011-07-18
Publication date: 2012-03-21
Anticipated expiration: 2021-07-18

Abstract

The utility model relates to a device for measuring coefficient of air resistance, belonging to an experiment measuring device. The device comprises a cylindrical container, a camera device, a simple pendulum, an air pressure monitor, a computer, an electromagnetic relay control device and a vacuum pump, wherein the cylindrical container is provided with a cover and is good in sealing performance and high in transparency, the simple pendulum comprises an iron support, an iron ball and a nylon wire, the computer is provided with video processing and data analysis software and is connected with the camera device and the electromagnetic relay control device in the container via data transmission lines, the iron ball has a smooth surface, the cover of the cylindrical container is provided with a valve communicated with the atmosphere and a valve communicated with the vacuum pump via a pipe, the air pressure monitor is connected with a pressure transducer via a data transmission line, and the cover of the cylindrical container can be opened and closed via a fixed switch. The device can easily, rapidly and accurately measure air resistance coefficients under different pressures and can overcome the defects of the prior art.

Description

Measure the device of coefficient of air resistance

Technical field

The utility model relates to a kind of device of measuring coefficient of air resistance, and it belongs to a kind of measuring device.

Background technology

The mensuration of coefficient of air resistance, when calculating various aircraft and in air, move with automobile the big or small calculating of suffered air resistance significant, also have important value for the configuration design of aircraft and automobile.For the mensuration of coefficient of air resistance, adopt wind tunnel experiment to measure mostly, but this method cost is too high at present, is not easy to promote.Chinese patent 97104627.1 discloses a kind of method of measuring coefficient of air resistance, but the size of the suffered coefficient of air resistance of car category that the result that this method is measured only is confined to be adopted in this experiment, can not reflect the essential attribute of air resistance.And this assay method can not reflect the influence of atmospheric pressure to coefficient of air resistance.

Summary of the invention

It is a kind of easy that the purpose of the utility model is to provide, the quick device that can accurately measure coefficient of air resistance under the different pressure simultaneously.Overcome the weak point of prior art.

The technical scheme of the utility model invention is following: measure the device of coefficient of air resistance, comprise hydrostatic column, camera head, single pendulum, air pressure monitor appearance, computing machine, electromagnetic relay control device, vacuum pump.Wherein, hydrostatic column is one: lid, good airproof performance, container that transparency is high are arranged; Single pendulum is by iron stand, iron ball, and nylon wire combines; Computing machine is equipped with Video processing and DAS, and links to each other with the electromagnetic relay control device with camera head in the container through data line; Iron ball is ganoid ball; Be furnished with on the lid of hydrostatic column and the valve of atmosphere and the valve that communicates with vacuum pump; Vacuum pump links to each other with valve through conduit; The Pressure monitoring appearance links to each other with pressure transducer through data line; The lid of hydrostatic column can realize opening or closing state through floatless switch.

Can regulate and set the air pressure in the closed container through vacuum pump, Pressure monitoring appearance and pressure sensing apparatus can be monitored the air pressure in the closed container in real time, guarantee that experimental data and result's is accurately reliable.Camera head and computer combined can accurately be noted iron ball damping vibration attenuation process is complete, and in conjunction with the associated video process software, it is required that accurate data are convenient to analyze to obtain experiment measuring.Relay control device and computer combined can be controlled the beginning and the end of iron ball motion, help improving the automaticity of this measurement mechanism.What the processing of experimental data and analysis were adopted is the mathematical function fit method, has guaranteed the reliability and the accuracy of measurement result.

The container of measurement mechanism requires good leak tightness; To guarantee the stable of container internal gas pressure; The transparency height of chamber wall is higher sharpness to be arranged when guaranteeing the amplitude fading image of camera head record iron ball, so that obtain experimental data more accurately, guarantees the degree of accuracy of measurement result.Select iron ball in air, to do the theoretical foundation of the motion model of damped vibration as measurement mechanism; Facilitate the use the related physical rule between damped vibration and the air resistance; The phenomenon of damped vibration simultaneously is directly perceived, and the related physical data are convenient to measure, and are convenient to obtain experimental result accurately.The subtle change real time record and the observation of its amplitude when the combination of camera head and computing machine can be done damped vibration to iron ball through its zoom function.Through two valves on the container cover and vacuum pump combination, can make things convenient for quick adjustment to the up-down of container internal gas pressure.Through the floatless switch on the container outer wall, can realize the conversion of container cover open and close state, be convenient to adjustment and replacing to related experiment device in the container, improved the adaptability of device.

The advantage of the utility model is following: can accurately set the pressure with control air, and the coefficient of air resistance under the different air pressure is measured, and simple in structure, easy and simple to handle.

Description of drawings

Fig. 1 is the structural representation of the utility model invention

1--vacuum pump 2--conduit 3-data line joint 4--valve 5--pressure transducer 6--container lid 7-hydrostatic column 8--camera head 9--iron stand 10--data line 11--electromagnetic relay 12--iron ball 13--nylon wire 14--Pressure monitoring appearance 15--computing machine 16--floatless switch.

Embodiment

Invention further specifies to the utility model below in conjunction with accompanying drawing and embodiment:

The structural drawing of this device is referring to Fig. 1: measure the device of coefficient of air resistance, comprise a hydrostatic column (7), camera head (8), single pendulum, Pressure monitoring appearance (14), computing machine (15), electromagnetic relay control device (11), vacuum pump (1).Wherein, hydrostatic column (7) is for having lid, good airproof performance, container that transparency is high; Single pendulum is by iron stand (9), iron ball (12), and nylon wire (13) combines; Computing machine (15) is equipped with Video processing and DAS, and links to each other with electromagnetic relay control device (11) with the interior camera head (8) of container through data line (10); Iron ball (12) is ganoid ball; Be furnished with on the lid of hydrostatic column (6) and the valve (4) of atmosphere and the valve (4) that communicates with vacuum pump; Vacuum pump (1) links to each other with valve (4) through conduit; Pressure monitoring appearance (14) links to each other with pressure transducer (5) through data line (10); The lid of hydrostatic column (6) can realize opening or closing state through floatless switch (16).

The principle of work and the process of this experimental provision are: earlier through gas-pressure survey meter (14) setting to measure the pressure values of air; Start vacuum pump (1) then; The valve that unlatching links to each other with vacuum pump (4); Pressure in the control closed container (7) after pressure reaches setting value, is closed the switch of vacuum pump (1) and valve (4).Through computing machine (15) control electromagnetic relay device (11); Make the nylon wire (13) that links to each other with iron ball (12) depart from the vertical direction certain angle; And iron ball (12) is in steady state (SS), opens camera head (8) then, the power supply of closing electromagnetic relay (11) through computing machine (15) simultaneously; Make iron ball (12) begin to do the damped vibration under the lower resistance, note the attenuation of amplitude through camera head (8).The video data of taking with the Video processing software processes in the computing machine (15), is obtained the data that amplitude is decayed in time.These data recording are got off,, can calculate the coefficient of air resistance size under this kind air pressure in conjunction with the related physical rule and the mathematical function fit method of damped vibration.If will measure the resistance coefficient under other pressure, only need to regulate respectively and the valve (4) of atmosphere and the valve (4) that communicates with vacuum pump, adjust to the pressure of setting after, repeat aforesaid operations then and get final product.

Claims

1. measure the device of coefficient of air resistance, comprising: hydrostatic column (7), camera head (8); Single pendulum; Pressure monitoring appearance (14), computing machine (15), electromagnetic relay control device (11); Vacuum pump (1) is characterized in that: hydrostatic column (7) is: lid, good airproof performance, container that transparency is high are arranged; Single pendulum is by iron stand (9), iron ball (12), and nylon wire (13) combines; Computing machine (1) links to each other with electromagnetic relay control device (11) with the interior camera head (8) of container through data line (10); Be furnished with on the lid of hydrostatic column (6) and the valve (4) of atmosphere and the valve (4) that communicates with vacuum pump; Vacuum pump (1) links to each other with valve (4) through conduit (2); Pressure monitoring appearance (14) links to each other with pressure transducer (5) through data line (10).