Optimization of electrostatic sensor for velocity measurement based on particle swarm optimization technique

Electrostatic sensors are broadly applied to measure velocity of solid particles in many industries because controlling the velocity particles improves product quality and process efficiency. These sensors are selected due to their robust design and being economically viable. Optimization of different electrode sizes and shapes of these sensors is required to find the ideal electrodes associated with maximum spatial sensitivity and minimum statistical error. Uniform spatial sensitivity is a crucial factor because it would lead to increase similarity between the measured correlation velocity and true mean particle velocity. This thesis proposes a new method to optimize different parameters of electrodes for electrostatic sensors. This technique identified characteristics of the electrostatic sensor in a MATLAB code called Particle Swarm Optimization (PSO). A mathematical model of various electrodes to compute spatial sensitivity and statistical error was applied to extract geometric size information of electrodes to detect suitable equations. To validate the proposed method, different values of electrode designs were applied in experimental tests conducted in a laboratory to measure the velocity of solid particles. The experimental results were optimized through Response Surface Methodology (RSM), an optimization technique for experimentation. The optimized results showed that spatial sensitivity of circular-ring electrode is more uniform in comparison to the other electrodes. The optimal length of circular-ring electrode was between 0.577 cm and 0.600 cm. In addition, the best thickness for the electrodes was between 0.475 cm and 0.500 cm. A close agreement between optimization and experimentation verifies that the proposed method is feasible to optimize physical sizes of electrostatic sensor electrodes. These results provide a significant basis of the effect of geometric dimensions on the sensing characteristics of electrostatic sensors

Modelling and simulation of different electrode size for electrostatic sensors

Electrostatic sensor has been widely used in process industry in addition this sensing approach has attracted significant attention of flow measurement community because of its advantages including robustness and low costs. This paper focuses on the theoretical analysis of several electrostatic electrodes, including ring, quarter-ring, pin, and rectangular; after that, they are mathematically modelled and simulated by Mathcad software. The geometric measurements of electrodes are considered as important parameters, which affect the results of simulation. However, spatial sensitivity and statistical error are the sensing characteristics of electrodes, which play major roles in modelling these electrodes. The thickness of an electrode, as a parameter influencing spatial sensitivity, is investigated in this study. Increasing the thickness of electrode leads to increase both spatial sensitivity and statistical error while maximum spatial sensitivity and minimum statistical error are desirable parameters. Therefore, the best thickness value of an electrode must be determined to achieve the required uniform spatial sensitivity. Good verification between experimental tests and the mathematical model suggests a reasonable model of electrostatic sensor electrodes

Using pyroelectric sensors to detect continuous infrared radiation

This paper focuses on an optimized method for detecting continuous infrared rays make use of Pyroelectric devices. Now, Pyroelectric devices are usually very sensitive to changes in infrared radiation in the presence of an object when transfers or radiation is connected or disconnected. In this new approach, the thermo-electric cooler is employed to active temperature sensors instead of conventional modulation. They use mechanical parts, which are complex and un-reliable. The most of the sensor consists of a number of important restrictions, which are expected to be eliminated by a new method in this study. To simulate the thermal and electrical behavior of the detector, the equivalent electrical circuit is needed that will be proposed.The practical results of Pyroelectric sensor are sent to a computer by a digital oscilloscope, and then they are monitored and analyzed. After that, the model is simulated with MATLAB software. Finally, practical and theoretical results compared with each other and a good agreement of them is shown and confirms the validity of the model

The effects of distance on velocity measurement for different shapes of electrostatic sensor electrodes

Velocity measurement has significant role in several industries that cope with particles to save power consumption and to improve quality of particles. This paper describes the effect of distance on velocity measurement for different shapes of electrodes for example pin, circular, rectangular, and quarter ring electrode. This distance is referred to separation of electrodes. Electrostatic sensors are suitable to measure the velocity of particles due to their inexpensive, simplicity and robust. These shapes of electrodes are modeled by mathematical equations and analyzed by Mathcad software. In addition, velocity is measured in laboratory by different shapes of electrodes in different distances. Cross correlation method is experimentally used to measure the velocity. Increase the distance between electrodes leads to increase the time lag, but velocity remains constant. The results of modeling electrodes and experimental tests are compared with each other and they verify that these electrodes are more reliable in industries in addition to cost- effectiveness and high efficiency