Theoretical And Experimental Study On Amplitude Distribution Of Light Scattering Signal Of Particle Count Sensor

Laser airborne particle counter (LAPC), based on light scattering of particle, is specially used in clean-room environment monitoring. Particle counting sensor is LAPC’s core component, its parameters directly determine the performance of counter. This parper introduced light scattering signal amplitude distribution to characteristic the particle counting sensor, researched light scattering signal amplitude distribution by theoretically and experimentally, explored a kind of effective means for optimal design of sensor.This paper established finite element simulation model of air and particle flow in light scattering airborne particle counting sensor basing on Ansys Fluent 14 software environment. For one thing, It can provide the spatial distribution of particles in the photosensitive area to analyze sensor’s light scattering signal amplitude distribution theoretically, for another, it can provide theoretical guidance for optimal design of sensor’s sample path. Basing on simulation calculation in particle counter sensor, provided theoretical calculation medel of light scattering signal amplitude distribution of particle counting sensor, calculated scattering light signal amplitude distribution of 0.4μm、0.5μm and 0.6μm PSL particle of experimental particle counting sensor. Meanwhile, in experiment, measured scattering signal amplitude distribution of 0.4μm、0.5μm and 0.6μm PSL standard particle, compared them with theoretical results and gived analysis and discussion, that is, experimental and theoretical results have good consistency, so as to verify the validity of theoretical calculation method. And on the basis of theoretical and experimental research, evaluated applying of light scattering amplitude distribution of particle counting sensor on sensor’s performance, light path design and design of structure of nozzle. In addition, this parper intuitively reveals the particle flow in the sensor through finite element simulation of particles and air flow in particle counting sensor, proposed a kind of optimization design of nozzle structure of sample path, these provided theoretical guidance for optimal design of particle counting sensor. In conclusion, research work of this parper have an important reference value on optimization design of light scattring particle counting sensor.