Photoelectric Turbidimeter Research And Design

The water is essential to people's life. Turbidity is one of the important parameters to appraise the water quality. With the improvement of people's living level. The request to water quality is stricter than before. To change the state of importing more turbidimeters(especially online turbidimeter) from overseas. It is essential to develop a high-quality online turbidimeter. So we started the research of this project.In this thesis we first analyzed the development and application of turbidimeters all over the world and the features of products produced by several famous campanise.Some problems were concluded on the process of turbidimeter research in our country; And analyzed several principles of turbidimeter measure and the relation between turbidity and the strength of scattered light. Then we decided to design a turbidimeter with the ratio principle based on scattered light and transmitted light to improve the linearity level. After that we introduced the design of the sensor of the turbidimeter and described several problems for the design of sensor in detail and the function and design of hardware and software.According to the bubble influence to the turbidimeter signal,stray light and environmental light in water sample and nonlinearity.We discussed and analyzed them more carefully and designed several different signal processing algorithmAt last we used virtual instrument technology to design an interface for receiving and displaying the turbidimeter data based on serial interface of computer and LabWindows/CVI software of NI Corporation .So Improved the speed of research and reduced the costs of production.