PM2.5 detection by cyclone separator combined with SH-SAW sensor

Abstract

In this research, a particulate matter PM2.5 monitoring device is designed and developed, including the shear horizontal surface acoustic wave (SH-SAW) sensor combined with a cyclone separator. Aerosols generated by incense smoke will be separated and sampled inside the designed cyclone separator first, and the sampled PM2.5 particles will be introduced into the sensing area of SH-SAW chip for the detection. From the CFD simulation, the designed cyclone separator, 0.2 mL microcentrifuge tube with 0.5 mm diameter of inlet and outlet, which has the separation cutoff diameters (d 50 ) at 2.5µm, and the required inlet volumetric flow rate is 0.125 LPM simulated. Experiment results demonstrate the performance of SAW sensor by monitoring the PM2.5 emitted from incense smoke, and the sensitivity of sensor is approximately 9Hz/ng. Furthermore, the PM2.5 concentration test shows an obviously higher accuracy with the designed cyclone separator added than barely SAW sensor.