An approach to the design and fabrication of a microprocessor based flow meter using resistance and semiconductor probe
01 Sep 2001-Iete Technical Review (Institution of Electronics and Telecommunication Engineers)-Vol. 18, Iss: 5, pp 355-360
TL;DR: An approach to the design and fabrication of a mass flow meter of a fluid using heat transfer technology is presented and experimental results conform to the theoretical analysis that the bridge output follows the mass flow rate linearly if the flow is stream line.
Abstract: An approach to the design and fabrication of a mass flow meter of a fluid using heat transfer technology is presented. The method uses the application of a simple matched pair of transistors as the flow transducer and compares the results with another flow transducer using a platinum resistance temperature detector. The effect of the temperature of the fluid is eliminated using the bridge circuit with the reference temperature probe placed in the static reference bath within the flow meter. The experimental results conform to the theoretical analysis that the bridge output follows the mass flow rate linearly if the flow is stream line. The effect of turbulence makes the output nonlinear. However a low cost microprocessor is used to linearise the flow data and display the flow value in digital form. The method used is a low cost one and is experimentally tested for flowing water at room temperature.
Citations
More filters
Book•
22 Sep 2009
TL;DR: The Flow Measurement Handbook as discussed by the authors provides a wealth of practical advice on the design, operation, and performance of a broad range of flowmeters, including orifice plate meters, venturi meters and standard nozzles.
Abstract: Flow Measurement Handbook is an information-packed reference for engineers on flow measuring techniques and instruments. Striking a balance between laboratory ideal and the realities of field experience, this handy tool provides a wealth of practical advice on the design, operation, and performance of a broad range of flowmeters. The book begins with a brief review of fluid mechanics principles, how to select a flowmeter, and a variety of calibration methods. Each of the following chapters is devoted to a class of flowmeters and includes detailed information on design, applications, installation, calibration, operation, and advantages and disadvantages. Among the flowmeters discussed are orifice plate meters, venturi meters and standard nozzles, critical flow venturi nozzles, positive displacement flowmeters, turbine and related flowmeters, vortex shedding and fluidic flowmeters, electromagnetic flowmeters, ultrasonic flowmeters, and coriolis flowmeters. Also covered are mass flow measurements using multiple sensors, thermal flowmeters, angular momentum devices, probes, and modern control systems. Many chapters conclude with an appendix on the theory behind the techniques discussed.
196 citations
TL;DR: A very simple linearization technique of a p-n-junction-type anemometric flow sensor has been proposed, and its performance characteristic has been experimentally determined.
Abstract: A p-n-junction-type flow sensor is used to measure the mass flow rate of a fluid through a pipeline by using anemometric principle. In this transducer, the cooling effect of a flowing fluid on the forward resistance of a constant-current or a constant-voltage p-n junction diode is utilized to sense the mass flow rate of the fluid flowing in contact with the diode surface. However, the main drawback of the sensor is that its flow characteristic is nonlinear. In this paper, a very simple linearization technique of a p-n-junction-type anemometric flow sensor has been proposed. The theoretical characteristic equation of this sensor has been derived. A prototype unit has been developed and fabricated, and its performance characteristic has been experimentally determined. The experimental results are reported in this paper. From these experimental data, a very good linear characteristic of the proposed flow sensor has been observed.
13 citations
Cites background or methods from "An approach to the design and fabri..."
...This technique is very simple, but the response characteristic of the sensor is nonlinear [4], [14]....
[...]
...A nonlinear relation of measured output with mass flow rate has been observed in thermistor anemometers [18], p-n junction anemometers [14], [20], and hot-wire anemometers [4], [14]....
[...]
...In this technique, the cooling effect of a flowing fluid on a constantcurrent or a constant-voltage heating-element-like hot wire [4], [14], a thermistor [18], and a p-n junction diode [20] changes the resistance of the element, and this change in resistance...
[...]
...In a practical measurement circuit, an additional linearization technique is used for anemometric flow sensors [14]....
[...]
TL;DR: It can be observed that the among these three different selection of Genetic Algorithm,Rank selected GA is better than the other two selection (Tournament,Roulette wheel) in terms of the accuracy of final solutions, success rate, convergence speed, and stability.
Abstract: Estimation of a highly accurate model for liquid flow process industry and control of the liquid flow rate from experimental data is an important task for engineers due to its non linear characteristics. Efficient optimization techniques are essential to accomplish this task.In most of the process control industry flowrate depends upon a multiple number of parameters like sensor output,pipe diameter, liquid conductivity ,liquid viscosity & liquid density etc.In traditional optimization technique its very time consuming for manually control the parameters to obtain the optimial flowrate from the process.Hence the alternative approach , computational optimization process is utilized by using the different computational intelligence technique.In this paper three different selection of Genetic Algorithm is proposed & tested against the present liquid flow process.The proposed algorithm is developed based on the mimic genetic evolution of species that allow the consecutive generations in population to adopt their environment.Equations for Response Surface Methodology (RSM) and Analysis of Variance (ANOVA) are being used as non-linear models and these models are optimized using the proposed different selection of Genetic optimization techniques. It can be observed that the among these three different selection of Genetic Algorithm ,Rank selected GA is better than the other two selection (Tournament & Roulette wheel) in terms of the accuracy of final solutions, success rate, convergence speed, and stability.
7 citations
Cites background from "An approach to the design and fabri..."
...Bera et al.[5] shows a comparative study between the matched pair transistors flow meter and platinum resistance temperature detector....
[...]
01 Aug 2019
TL;DR: In this work, three different improved versions of original elephant swarm water search algorithm (ESWSA) is proposed and tested against the present problem of liquid flow control and ESWSA is found to be best efficient algorithm with respect to success rate and computational time.
Abstract: In process industry, liquid flow rate is one of the important variables which need to be controlled to obtain the better quality and reduce the cost of production. The liquid flow rate depends upon number of parameters like sensor output voltage, pipe diameter etc. Conventional approach involves manual tuning of these variables so that optimal flow rate can be achieved which is time consuming and costly. However, estimation of an accurate computational model for liquid flow control process can serve as alternative approach. It is nothing but a non-linear optimization problem. In this work, three different improved versions of original elephant swarm water search algorithm (ESWSA) is proposed and tested against the present problem of liquid flow control. Equations for response surface methodology and analysis of variance are being used as non-linear models and these models are optimized using those newly proposed optimization techniques. The statistical analysis of the obtained results shows that the proposed MESWSA has highest overall efficiency (i.e. 45%) and it outperformed the others techniques for the most of the cases of modeling for liquid flow control process. But one of the major disadvantages of MESWSA is its slow convergence speed. On the other hand, ESWSA is better for finding the best fitness and LESWSA has better stability in output. Moreover, LMESWSA is found to be best efficient algorithm with respect to success rate and computational time. However, all algorithms and models can predict the liquid flow rate with satisfactory accuracy.
7 citations
28 Dec 2017
TL;DR: It is observed that among the three different selection rank selected hybrid Genetic AlgorithmNeural network (GA-ANN) model is better than the other two selections (Tournament & Roulette wheel) in terms of the accuracy of final solutions, minimum absolute error, computational time, and stability.
Abstract: Designing a highly accurate model for liquid flow process industry and controlling the liquid flow rate from experimental data is an important task for engineers due to its nonlinear characteristics. Efficient optimization techniques are essential to accomplish this task. In most of the process control industry flow rate depends on a multiple number of parameters like sensor output, pipe diameter, liquid conductivity, liquid viscosity & liquid density etc. In traditional optimization technique its very time consuming for obtaining the optimum flow rate which is manually controlled in the process. Hence the different computational optimization processes are utilized by using different intelligence techniques. In this paper three different selection of hybrid Genetic AlgorithmNeural network model is proposed & tested against the present liquid flow process. Equations for neural network are being used as non-linear model and these models are optimized using the proposed different selection of Genetic optimization techniques which is based on mimic of the genetic evolution of species that allow the consecutive generations in population to adapt their environment. From the numerical result it is observed that among the three different selection rank selected hybrid Genetic AlgorithmNeural network (GA-ANN) model is better than the other two selections (Tournament & Roulette wheel) in terms of the accuracy (98.42%) of final solutions, minimum absolute error (0.6463), computational time, and stability. RÉSUMÉ. En raison de ses caractéristiques non linéaires, la conception d’un modèle extrêmement précis pour l’industrie de supervision de la dynamique des fluides et le contrôle du débit de liquide à partir de données expérimentales est une tâche importante. Des techniques d’optimisation efficaces sont essentielles pour accomplir cette tâche. Dans la plupart des industries de supervision, le débit de liquide dépend de nombreux paramètres tels que la sortie du capteur, le diamètre de la conduite, la conductivité, la viscosité et la densité du liquide, etc. Dans la technique d'optimisation traditionnelle, il prend beaucoup de temps pour obtenir le débit optimal lors du contrôle manuelle. Par conséquent, les différents processus d'optimisation informatique sont utilisés à l’aide de différentes techniques intelligentes. Dans cet article, trois choix différents de modèles hybrides d'algorithme 450 JESA. Volume 50 – n° 4-6/2017 génétique et de réseaux neuronaux sont proposés et testés par rapport au processus actuel de la dynamique des fluides. Les équations du réseau de neurones sont utilisées comme modèles non linéaires et ces modèles sont optimisés à l'aide de ces choix différents de techniques d'optimisation génétique proposée, qui repose sur une imitation de l'évolution génétique d'espèces permettant aux générations consécutives de la population d'adapter leur environnement. Le résultat numérique montre que, parmi les trois choix différents, le modèle hybride d’algorithme génétique réseau de neurones artificiels (GA-ANN en anglais) est meilleur que les deux autres choix (Tournoi et roulette wheel) en termes de précision (98,42%) du résultat final, d’erreur absolue minimale (0,6463), de temps de calcul et de stabilité.
7 citations
References
More filters
TL;DR: In this paper, two integrated thermal gas flow sensors have been developed for the simultaneous measurement of the velocity and the direction of gas flow, and the sensors were fabricated using a commercial CMOS process followed by silicon micromachining.
Abstract: Two integrated thermal gas flow sensors have been developed for the simultaneous measurement of the velocity and the direction of gas flow. The sensors were fabricated using a commercial CMOS process followed by silicon micromachining. The first sensor consists of two crossed dielectric microbridges, while the second device is based on a dielectric membrane. Both sensors contain integrated heaters and two orthogonal pairs of integrated thermopiles, which constitute a vector probe for the two components of the velocity of gas flows. In contrast to previous designs, the reported sensors show a linear output as a function of flow velocity, with sensitivities of 0.19 and 1.9 V W-1 m-1 s, respectively. Gas flow direction measurements with average errors of 1.7 degrees and 0.6 degrees , respectively, are achieved. We also demonstrate gas flow velocity and direction measurements using the rear of the membrane devices, which opens new perspectives for the packaging of integrated flow sensors. In this configuration a sensitivity of 0.67 V W-l(m/s)-l and an angular resolution of 3.1 degrees were obtained.
73 citations
10 May 1994
TL;DR: In this paper, a self-heated thermistor was used as a probe for low flow rate measurements, which is based on hot-wire anemometry, and the signal was transformed from the flow rate domain to the time domain by the digital waveform synthesis.
Abstract: A digital anemometer using a self-heated thermistor as a probe has been developed for low flow rate measurements. The principle of measurement is based on hot-wire anemometry. To enhance the probe sensitivity to the flow rate while reducing the convection due to self-heating to a minimum, the thermistor is kept to the lowest possible temperature for exhibiting the negative resistance. The heat removed from the thermistor is analyzed and compared with the measured results, to derive the characteristic function which relates the voltage across the thermistor to the flow rate and temperature. This function is transformed from the flow rate domain to the time domain by the digital waveform synthesis. The carrier signal thus generated is pulse-width-modulated by the output of the probe, to provide the digital representation of the flow rate under measurement. The cross-sensitivity of the probe to the fluid temperature is compensated by scaling the carrier amplitude. Exempting linearization and compensation for the convection, this process of quantization makes a high accuracy flow rate measurement possible with a simple configuration. >
37 citations
TL;DR: In this paper, the forward current through the p-n junction is switched alternately between two fixed values, and the difference between the corresponding voltages is shown to vary linearly with temperature.
Abstract: A temperature sensor based on the use of two forward-biased p-n junctions is known to exhibit good linearity. An alternative sensor configuration, based on the same principle, but employing only one p-n junction is presented in this paper. The forward current through the p-n junction is switched alternately between two fixed values, and the difference between the corresponding voltages is shown to vary linearly with temperature. This scheme eliminates the problems associated with close matching required for the two p-n junction sensors. Experimental results obtained with the proposed scheme are presented. A configuration to exploit the temperature dependence of the p-n junction incremental resistance is also presented. >
28 citations
TL;DR: In this article, the basic theory, experimental performance, and current status of flow sensors based on the use of surface acoustic waves (SAWs) are discussed, and an example of the performance that has been achieved is illustrated by a 73 MHz sensor that shows greater than 140 kHz change in frequency for variations in flow rate.
Abstract: The basic theory, experimental performance, and current status of flow sensors based on the use of surface acoustic waves (SAWs) are discussed. The sensor consists of a delay-line stabilized SAW oscillator heated to a suitable temperature above ambient, and placed in the path of the flowing fluid. Convective cooling caused by fluid flow changes the substrate temperature and thereby the oscillator frequency. Attractive properties of this sensor include high sensitivity, wide dynamic range, and direct digital output. An example of the performance that has been achieved is illustrated by a 73 MHz sensor that shows greater than 140 kHz change in frequency for variations in flow rate from 0 to 1000 ml/min. One of the limitations of the SAW flow sensor is its slow speed of response. This problem can be overcome by using a Lamb wave device fabricated on a thin membrane.
25 citations