Device and method for measuring ammonia gas based on femtosecond laser-induced plasma

Abstract

The invention discloses a device and a method for measuring ammonia gas based on femtosecond laser-induced plasma, the device comprises a flow field to be measured, a femtosecond laser, a focusing lens, a spectrograph, an ICCD camera and a computer, and NH3, such as NH3 / N2 mixed gas and NH3 / air combustion flame, is arranged in the flow field to be measured. The spectrograph is arranged on one sideof a flow field to be measured, the spectrograph and the ICCD camera are both connected with a computer, and laser emitted by the femtosecond laser forms a filament through the focusing lens and thenenters the flow field to be measured. The measuring device is simple, the measuring process is simple and convenient, the interference on the flow field to be measured is very small, and the real-time online measurement of NH3 in the closed and open flow fields can be realized.

Description

technical field [0001] The invention relates to the technical field of femtosecond laser spectroscopy, the field of plasma and the field of gas measurement, in particular to a method for measuring ammonia gas by femtosecond laser-induced plasma spectroscopy. Background technique [0002] Accurate measurement of flow field parameters such as temperature, velocity, component concentration, and mass flow rate is crucial for the development of advanced propulsion systems. Among them, accurate measurement of flow field temperature helps to improve combustion efficiency, reduce pollutant emissions and optimize combustion process. At the same time, accurate measurement of flow field temperature can provide accurate experimental data support for computational fluid dynamics (computational fluiddynamics, CFD) simulation software simulation. At present, there are mainly non-optical means and optical means for flow field temperature measurement. [0003] Non-optical means to measure ...

AI Technical Summary

Problems solved by technology

CARS temperature measurement technology has been developed very maturely, with high measurement accuracy, but the measurement system is relatively complex and can only achieve single-point measurement; Rayleigh scattering and filtered Rayleigh scattering temperature measurement technology can obtain two-dimensional temperature field distribution, but the measurement accuracy Relatively poor; TDLAS temperature measurement technology is low in cost and fast in response, but this technology is a path integration measurement method that does not have spatial resolution [6]; PLIF technology can be applied to temperature two-dimensional distribution measurement under complex composition conditions , but this method has significant limitations at high pressure

Images