Approach Of Fiber Grating Sensing Technology For Dynamic Strain And Cylinder Pressure Of Internal Combustion Engine

Controlling the operation of the engine to adapt to different conditions depends on the precise monitoring engine running, electric sensors are widely used in the world currently. As a sensing unit, the main advantage of fiber Bragg grating is the absolute measurement of wavelength encoding information. In addition, low insertion loss and narrow-band wavelength of reflection provides a benefit in a single-mode fiber on the reuse can be realized in the star-shaped fiber-optic network, serial, parallel and ring connections. This paper studies the application of Fiber Bragg Grating Sensing Technology in Internal Combustion Engines, in order to achieve internal combustion engine testing technology innovation.Fiber Bragg Grating can measure a variety of physical quantities: temperature, displacement, Vibration acceleration, pressure, electric current, magnetic field, sonar, liquid level, hydrocarbon gases, as well as torque, almost all of the traditional electrical sensors in the internal combustion engine can be replaced. This paper take the cylinder strain sensing and cylinder pressure sensing two fronts to explore.Dynamic strain test in internal combustion engine use CG125 single-cylinder four-stroke gasoline engine as platform. On the one hand, with the finite element software to simulate the engine cylinder strain analysis; on the other hand, comparing dynamic strain gage sensing system with FBG dynamic strain sensing system, experimental results are consistent. In addition, testing FBG dynamic strain sensing system on YN-D19 diesel engine, verify the dynamic response of FBG sensing system used in the feasibility of high-power diesel engine.Cylinder pressure test use CG125 engine as the research object, designed and packaged fiber grating pressure sensor, use of motor drag down CG125 engine to test fiber grating pressure sensor, fiber grating sensor measurements more consistent with the theoretical analysis.As the internal combustion engine is the thermal mechanism with high temperature and pressure, the parameters of engine are dynamic parameters, and the exiting fiber grating sensing system is mainly used in static condition and at room temperature. Therefore this study preliminary explore the fiber grating sensing technology in internal combustion engines.