Based On Ultraviolet Flame Detector Comprehensive Testing System Of Research And Design

With the development of the ignition technology, the flame detecting way has alsochanged greatly, from the initial thermocouple detection method, to ion rectifier, and then tothe current most widely used spectrum detection mode. In today’s society, fire become a threatto people life safety and the development of the society, one of the major hazard of fireprevention naturally became an important task currently, and flame detector as an importantpart of fire prevention, must become the focus of research object.In the field of aerospace,the flame detector also plays an important role,the pressure ofengine combustion chamber of the aerospace equipment with fuel,gas as fuel,the ignitiondevice, combustion in the combustion chamber,in some cases if ignition is failed, or for somereason ignition is normal after suddenly went out in this time, if it is not promptly to cut offthe fuel supply sources,it coule cause after flameout, because continue to put on the fuel andcause explosion accident. Therefore, in order to guarantee the normal work of the engine andspace staff’s life safety, must be detection effectively for the engine combustion chamberpressure fuel combustion state (fire or flameout), and timely feedback detection information.Compared with other flame detection method, ultraviolet detection method can avoidcomplicated background of the outside environment, it is greatly for reducing burden forsignal processing of the system, it is mainly based on photoelectric efficiency and electronicnumerous flow theory technology, ultraviolet signal convert to electrical signal, and thenprocessing electrical signal to the corresponding, so its reliability and signal noise ratio (SNR)is high, in addition, it also has features such as high sensitivity, fast response, the applicationcircuit of simple. Ultraviolet detection technology can test very weak signal, and can makerapid response for specific frequency band spectrum.Ultraviolet flame detector used in aircraft engine ignition system that referred in the subject,soit is strict requirements for its perfaormace,quality and life.In order to solve the problem that itis working environment requirements and production test and acceptace, this research hasbeen designed for ultraviolet flame detector in production assembly process for performancedebugging, performance test and acceptance test of ultraviolet flame comprehensive testsystem. The system is mainly composed of industrial control computer, three wire24v powersupply module, two wire volt power supply module, switching module, control module andsignal acquisition module.When user make the whole test and acceptance test forproducts,based on industrial control computer interface setting,realize test automation((haveto realize test procedure automation control, the test process automation monitoring, the testdata of automation acquisition and automatically print test report), in order to reduce artificial factors, improve the work efficiency and improve the accuracy of the test results.This paper describes the ultraviolet flame detector comprehensive test system overalldesign scheme, and analyses the ultraviolet flame detector work principle and fuel burnsradiation spectrum and flicker frequency characteristics of the flames, through the analysis ofthe source of mercury lamp, finally determined that by mercury lamp light fuel combustionsimulation of the ultraviolet radiation scheme. With ultraviolet flame detector workingprinciple for the design basis, the main performance indicators for design standards, designthe hardware module, analysis and testing, and debugging results and the main performanceindicators were comparred, analysis of the output parameters of power module, and samplingaccuracy of the signal acquisition module, and finally determined that the hardware circuitdesign in accordance with the design standards. At the completion of the man-machineinterface design, the whole system implemented on-line debugging, and at the same time often way different wire ultraviolet flame detector for the tests, the test equipment to realize theautomation in improving the work efficiency, at the same time, improve the detection ofaccuracy. The system has been used, and the operation is stable, and the performance is good.