Optimization of the optical particle counter for online particle measurement in high-pressure gas

With the aim to achieve fast and accurate online measurement of particle size and concentration in different high-pressure gas, the application of an optical particle counter (OPC) is extended from atmospheric pressure to high-pressure conditions (more than 2 MPa). But with the increase of the gas pressure, the performance of the OPC is reduced, resulting in the error of the tested particle size. In order to resolve this problem, an optimization model of optical window thickness is established for the optical sensor of the OPC based on the geometric optics theory. The effects of gas pressure, temperature, and medium on the optimized model are analyzed, which are helpful to improve the accuracy of the optical sensor. Finally, the feasibility, reliability, and accuracy of the method are verified through experiments. (C) 2019 Optical Society of America