Design And Development Of Measurement And Control System On Laser Particle Sizer

The rapid development of the powder industry has brought forward more requirements to the particle size measurement technology. It is so important to reflect particle size and distribution objectively and actually. Nowadays, in the many types of particle size measurement technologies, laser particle sizer, which is based on the light scattering theory, has been widely used because its advantages of accuracy, speediness and no-destructibiliy. However, there is still a gap between our country and the overseas advanced level, because of the delay of development.The measurement and control system of laser particle sizer includes hardware and software related to the measurement and control function in the instrument, it is the core part of laser particle sizer. The basic principle and mathematic model of laser particle size measurement are systematically studied in this paper, on the base of which, general design of measurement and control system is been carried out. The measurement and control system of laser particle sizer is composed by data collector and measurement & control software. The former is the hardware part which transforms the scattering light signals to digital signals, the latter is the software part running on PC.We expound the design and improvement of data collector in the paper. High performance chip TLC2254 is used in the signal amplifying. C8051F410 which is a low power SoC MCU provided with 12-bit A/D converter,24-channel analog input signals analog signals, is used as the main controlling chip.The measurement & control software is developed with Visual C++6.0 of Microsoft. By the technologies of graphics display and ActiveX, the functions of data transfer and display, data storage, mathematic modeling and particle size distribution solving are all accomplished, and then real measurement experiments are implemented to improve the reliability.The application of the Mie theory in particle size measurement domain is discussed at the end of the paper. We put forward a new accurate, effective and rapid arithmetic of Mie scattering light intensity. On the base of the arithmetic, a wide-angle laser particle sizer is designed and then simulated.