In this work, the effect of flow rate change, temperature, and fluid type are considered on meter factor in turbine meter with the aid of Computational Fluid Dynamics (CFD) simulation. Continuity and momentum equations along with the proper boundary conditions are numerically solved in a steady finite volume frame. SIMPLE algorithm is used for coupling the velocity and pressure field. For the simulation of turbulent flow, the RNG k-e, and for discretizing the advection scheme the second order upwind are used. The drag and lift force on turbine impellers, and the meter factor utilizing angular momentum balances are gained. The results show that the accuracy increases with temperature enhancement and is almost constant with augmenting flow rate. Moreover, the shift from heavy oil to light oil causes the measurement accuracy to increase.

One of the most common of measuring mass fluid flow rate through the pipes are orifice Flowmeter. Orifice Flowmeters work based on the fluid pressure difference before and after of the orifice which could be measured acual mass flow rate. The orifice pressure drop and the discharge coefficient are related on geometrical shape of orifice, the ratio of orifice diameter to the pipe diameter and Reynolds number of fluid flow. In this study, the performance and accuracy of an orifice flow meter for measuring the mass flow rate of cooling water in a sample thermal power plant is examined. In order to determine the water pressure drop on both sides of the discharge orifice, the orifice Flowmeter with connections taken into account and fluid flow inside it is simulated. Due to the turbulent flow of water, the standard k-e turbulence model is used. The performance orifice curve has been obtained numerically and it compares with the actual performance curve orifice obtained from experimental data. This comparision shows a good match. Also the orifice discharge coefficient obtained by numerical and experimental methods and compared with values given by valid standards that indicates good agreement. The numerical analysis has determined that maximum flow velocity occurs about one orifice diameter downstream of the orifice location and in this point, velocity of flow is more than four times the average velocity of flow in the pipe entrance.

The present study is a numerical model for prediction of turbine Flowmeter performance, using the equation of motion based on torque balance theory. In this model, numerical simulations were carried out for a 2-inch diameter G65 and PN/ANSI 150 gas turbine Flowmeter which was made by Vemmtec Company, in steady state, using Multiple Reference Frame (MRF) model and Standard k-ε turbulence model using Fluent software. In order to model torque balance equation and calculate angular velocity of rotor, a UDF (User Defined Function) code was created and was added to the software. To evaluate the model’ s accuracy, simulation results were compared with experimental data which was obtained from manufacturer of the meter. The difference between the simulation results and experimental data was 0. 16%, approximately, which indicates the validity of the proposed model in simulating of turbine gas Flowmeter performance. The results obtained from the simulation depicted that the velocity distribution asymmetry was more than 0. 4Qmax at the downstream of the meter, and because this phenomenon had no negative effect on flow measurement, the suitable length for the flow development for the downstream of meter was done using simulation at least 10 times the diameter of the pipe was proposed. Therefore, using the proposed model, the capital cost of design and optimization of turbine Flowmeters can be reduced.

Using the Faraday's Law of electromagnet induction, the electromagnetic Flowmeters are use to measure the industrial process flow rate of the fluids. In these devices, the windings around the pipe are designed to make the required magnetic field and electrodes which are mounted on two sides of the pipe wall, are used to measure the induced voltage in proportion with the flowing liquid rate. This paper presents the design and optimization of electromagnetic Flowmeter for conductive liquids. In this respect, a two dimensional mathematical model by Finite Difference (FD) numerical solution approach is used for calculation of electric potential difference between the electrodes. The basic concepts of the electromagnetic Flowmeters design and simulation have been presented using m-file programming in Matlab software. Then, with respect to the fact that fluid flow depends on two variables: liquid level and conductivity coefficient of liquid and pipe bed, a three layer neural network is used for an accurate calibration of electromagnetic Flowmeter. In this new approach, for a circular cross-section pipe, the correction factor, used for the calibration, is accurately estimated finally, simulation results are provided to show the accuracy of the applied technique in this paper.    

With increasing importance of flow measurement in industries, especially in petrochemical and water and wastewater, and their need to reduce the installation space and increase the accuracy, it is necessary to improve the existing Flowmeters and produce new types. In the last two decades, the V-Cone Flowmeter has received the special attention of researchers with features such as reducing the required initial length, lower pressure drop compared to other types, and the ability to be used in two-phase flows. Also, several researches were done to improve the Flowmeter geometry. But one of the things that is less discussed is how to connect the Flowmeter stand to the body (Flowmeter nose). Therefore, in this research, experimental and numerical study of a new case that has a continuous nose, and comparing it with standard types including pointed, curved and elbow, have been done. Using test results, correlations were proposed to estimate the pressure drop between two Flowmeter sensors and the pressure loss. Calculations showed that the relative error of pressure drop calculation in the range of Reynolds numbers investigated (5.88 × 104 to 9.80 × 104) is about -0.73%. Numerical simulation showed that the continuous type with the highest level of disturbance (about 3.5% more than the minimum value) causes the increase of fluctuations in the value shown by the pressure gauge located downstream and the error in the calculation of the discharge coefficient. Also, changing the shape of the Flowmeter nose caused only minor changes in the size of the vortexes.

Accurate measurement of gas flow is a basic need in domestic use. Diaphragm gas meters are currently used to measure domestic gas consumption, which is a very old and inaccurate technology. In recent years, the use of thermal MEMS Flowmeters has been growing due to their small size, low power consumption, and good accuracy, but their limited measurement range has prevented them from being used to measure domestic gas consumption. In order to eliminate this limitation, in the present study, a bypass system similar to capillary tube Flowmeters was introduced, which it has also been used in several commercial microthermal Flowmeters. This system must be designed in such a way that an acceptable flow enters the bypass (microchannel). Therefore, in this study, for the first time, the effect of different geometrical parameters on the flow rate to the bypass in the flow range of domestic consumption was studied by simultaneously solving turbulent and laminar flow equations through fluid dynamics simulation. According to the results, with the higher the height of the bypass channel is, the smaller the diameter of the laminar flow element is and the less bypass-laminar flow element distance is, more gas enters the bypass. Finally, the channel height of 160 micrometers, the distance of 2 mm between bypass entrance and laminar flow element, and the square arrangement of the laminar flow element with a diameter of 1. 8 mm can be appropriate. In these specifications, 100 to 220 percent more flow enters the bypass than most other configurations of the work.

Introduction: Agriculture sector is the main consumer of water in Iran. According to statistics, global dependency of agriculture sector to underground water is 37. 5% while in the Middle East the rate is 46. 2% but in Iran, this amount exceeds 62%. This statistic indicates that underground water consumption by agriculture sector in Iran is much higher in comparison with other parts of the world bringing up more challenges to the country. As a result, the Iranian government has long tried to apply diverse strategies to conserve agricultural water by the sector. One of these strategies which has recently been executed by the government, is installing intelligent Flowmeter on agricultural wells. Accordingly, farmers are forced to use this strategy to consume less water, thereby, managing underground water more efficiently. Notwithstanding the different extension programs applied by the government to encourage farmers to accept this new strategy more satisfactorily, farmers are not satisfied by the strategy causing them to resist against installation of Flowmeter on their agricultural wells. Although compulsory, if government could encourage farmers to use this strategy more willingly, they will conduct a better behavior towards water conservation. Therefore, studying why farmers are not satisfied by this strategy of water management is of critical importance to policy makers and practitioners. To that end, the main purpose of this research was to investigate factors affecting farmers’ satisfaction from installing intelligent Flowmeter on their agricultural well applying theory of Values, Beliefs, and Norms. The theory has been applied by many scholars to investigate environmental conservation behaviors but all of them have addressed voluntary behaviors. We wanted to know whether it could be applied to study compulsory behaviors as well. Materials and Methods: This cross-sectional survey research was conducted in Mahidasht county, Kermanshah province, Iran. According to the statistics, there are currently 352 intelligent Flowmeters installed on the agricultural wells in the region irrigating more than 8000 hectares of agricultural lands. Using stratified random sampling technique, 120 farmers were chosen. Data were gathered during spring and summer of 2016 through a questionnaire validity of which was confirmed by faculty members and experts of agricultural extension and irrigation. The reliability of the questionnaire was confirmed applying Cronbach’ s alpha coefficient analysis. Data were analyzed applying AMOS software. We used path analysis technique to address research objectives. Results and Discussion: Main results indicated that farmers are satisfied with an average level from installing the intelligent Flowmeter on their wells. Most farmers have not been trained by the government on how to use the intelligent Flowmeter efficiently. Furthermore, farmers mentioned that they have not been supported by the government after installation of the Flowmeter. Most respondents mentioned that it is not fair to force farmers to install Flowmeter on their wells as they cannot afford it. Also, they believed that this strategy does not decrease water consumption by farmers and considered the strategy as an insufficient solution for water management. Path analysis applying AMOS software showed that attitude towards water conservation, water conservation value, attitude towards installation fairness, attitude towards installation usefulness, income, subjective behavioral control, access to resources, education, and extension training afterward the installation, have significant positive effect on farmers’ satisfaction. A surprising finding was the insignificant influence of personal and social norms on farmers satisfaction which was against the theory of Values, Beliefs, Norms. The main reason behind this finding was that the sample was almost homogenous in terms of their norms regarding water conservation behavior. Therefore, this research cannot address whether farmers norms is influencing their satisfaction of installing Flowmeter on their wells. Conclusion: theory of Values, Beliefs, and Norms could be applied to address compulsory water management behaviors by farmers. In fact, government could persuade farmers to accept compulsory water management strategies more willingly if it can change farmers’ attitudes and beliefs concerning environmental crisis. According to the result, farmers’ attitude towards water conservation has the highest effect on satisfaction followed by contextual factors of income and education. The findings revealed that lack of extension training on how to manage water more efficiently in the region is obvious. The findings of this study reveal that if government and policymakers prefer that farmers install Flowmeter on their wells voluntarily even though it is compulsory, then they should invest more on changing farmers’ attitudes and beliefs towards water and environmental crisis through developing more extensive training programs in this regard. The results indicated that extension programs could have significant direct and indirect effect on farmers satisfaction and behavior. Therefore, it is suggested that different extension programs to be developed to affect farmers’ attitudes and beliefs regarding water conservation as the result shows the importance of attitude on farmers’ behavior towards water management.

Among the flow measurement technologies, the ultrasonic cross-correlation Flowmeter (UCCF) has received much attention due to its high accuracy, performance independency from sound speed and no pressure drop. In industrial plants, due to space constraints and equipment special arrangement, the Flowmeter is not always located at the ideal position. Under these conditions, the calibration factor plays an important role in increasing the accuracy of the flow measurement. The calibration factor is the function of the flow Reynolds number, the straight pipe length at the upstream of the Flowmeter and the roughness of the pipe. In present study, with the aid of CFD simulation and using Reynolds Stress Model (RSM), the air flow inside the pipe was simulated in range of Reynolds number from 3. 16×104 to 3. 16×105. Then, with the aid of UCCF analytical model, the effect of the mentioned parameters including flow Reynolds number, the straight pipe length at the upstream of the Flowmeter and the roughness of the pipe, on the performance of the UCCF were investigated. The simulation results show that the changes in shape and curvature of velocity profile inside the pipe has an important role in analyzing and interpretation of the changes in calibration factor. As the flow Reynolds number increases, the velocity profile at the pipe section becomes flatter, so the calibration factor increases. The results also demonstrate that as the flow moves inside the pipe (prior to fully developed length), the curvature of the velocity profile increases firstly and then decreases. In contrast, the calibration factor decreases firstly and then increases. It was also concluded that by changing the pipe material from carbon steel to cast iron and increasing the pipe roughness, the velocity profile becomes more rounded, so the calibration factor decreases.

Background & objectives: Ischemic stroke is the third leading cause of death and disability in most of the human societies. There is no effective treatment due to complexity of the pathophysiological mechanisms. Today, more researches are designed to introduce involving factors and new treatment strategies in brain ischemia. The objective of this study is to introduce an experimental model of the focal cerebral ischemia in rat with increased success rate and low mortality rate.Methods: In this research 32 male rats (Sprague-Dawley) were studied as in four experimental groups. Animals were anesthetized with chloral hydrate (400 mg/kg, ip). Focal cerebral ischemia was induced by intraluminal filament method. A silicon coated nylon filament was used for middle cerebral artery occlusion. Regional cerebral blood flow was monitored by laser Doppler Flowmetery to guide the insertion of the filament into the vascular pathway. 24 hours after ischemia (90 minutes), animals were assessed for neurological outcome, infarct volume and brain edema formation. A new and reformed neurological test was used for evaluation of neurological deficits. 2- millimeter coronal sections were collected from 6 levels of the brain and stained,digitized and quantified by using an image analysis system. Ischemic brain edema formation was investigated by brain water content detection.Results: Induction of ischemia in ischemic group, seriously caused impairment of motor functions (neurological deficit score 4±0.5) While sham operated rats had no motor deficit and infarction. Mean total infarct volume of left (ischemic) hemisphere was 402±43 mm3 and 62.7 percent of infarction occurred in cortical regions of the brain. Induction of focal cerebral ischemia in the left (ischemic) hemisphere of the brain significantly increased water content (84±0.23 percent) compared to both hemispheres of sham group and right hemisphere of the same group. Success rate of ischemia induction was 100 percent and there was no mortality due to technical problems.Conclusion: Our findings indicate that continuous recording of regional cerebral blood flow using laser Doppler Flowmeter had significant role in increasing success rate and lowering mortality rate in the present model of ischemic rat. This experimental model with high success rate and low limitation can be used for brain ischemia studies and evaluating new therapeutic strategies.

Lateral intakes are one of the most common structures of dividing the flow in irrigation and drainage systems. Due to complexity of the velocity profile in divide zone, measurement of mean flow velocity is become very difficult. In this paper the velocity profile of lateral intakes were calculated whit high accuracy by using of artificial neural network. To do this, the following steps have been taken: (1) Computational fluid dynamic model of lateral intakes in various wide ratios were modeled and validated with a published experimental study. The results shown that the numerical model has high accuracy in modeling the flow of lateral intakes. (2) By using the computational fluid dynamic model, the velocity that measured with a hypothetical Flowmeter that placed at the middle of the cross section were extracted. (3) A multilayer perceptron model were designed to predicting the mean flow velocity by using of the Flowmeter measured velocity, width ratio and longitudinal coordinate. The results shown that using of combination of Flowmeter measurement and artificial neural network could predict the accurate mean flow velocity in lateral intakes.