Electrical submersible pumps (ESPs) are one of the most effective artificial lift methods for increasing hydrocarbon production in high-rate wells; however, free gas in the production stream frequently causes issues such as gas locking, reduced pressure head, increased mechanical wear, and eventually pump failure, particularly in reservoirs with gas breakthrough or active gas caps. Traditional diagnostic workflows relied on pump performance curve matching with nodal analysis, which were unable to detect dynamic performance anomalies. In this study, an enhanced nodal analysis methodology was applied to assess the ESP performance under gas–liquid flow conditions using real-time field data. The methodology combined downhole intake and discharge pressures, surface well testing data, and Variable Speed Drive (VSD) output current. The field baseline was validated with Petex PROSPER software, achieving high predictive accuracy with a relative error of 2.82% for the oil production rate and <0.50% for the downhole pressures. The framework was used on Well A in the Peshkabir field (Kurdistan Region of Iraq), where gas breakthrough caused discharge pressure collapse from 2,572 psi to 1,360 psi (47.12%), a 23.08% reduction in VSD output current from 390 A to 300 A, and an intake pressure rise from 1788 to 1860 psi, signifying dynamic motor unloading and ESP head degradation. Following a gas shut-off intervention using coil tubing to close Sliding Side Door (SSD) #1, #2, and #3 in the lower completion, the discharge pressure climbed to 2850 psi (109.56%), the intake pressure remained steady at approximately 1770 psi, and VSD current restored to approximately 380 A (26.67%). The results indicated that the intake–discharge pressures, well test data, and VSD current telemetry serve as a reliable method for diagnosing gas interference in packer-completed wells, allowing better reservoir management without requiring pump curve detail

Locally sourced crude oil from Iraqi Kurdistan contains recalcitrant organosulfur compounds that impair air quality, corrode refinery equipment, and hinder compliance with fuel sulfur regulations. This study isolated a Pseudomonas sp. closely related to the Pseudomonas aeruginosa from oil-contaminated soil near Kashy Refinery (Duhok Province, Kurdistan Region, Iraq) and evaluated its biodesulfurization potential as an environmentally friendly alternative to hydrodesulfurization. Batch experiments were conducted at 34 °C and atmospheric pressure using mineral salts medium supplemented with 1%, 3%, and 5% (v/v) Tawki crude oil. The highest sulfur removal efficiency of 83.33% was obtained at 1% (v/v) crude oil after 10 days of incubation, as determined by X-ray fluorescence, with visible emulsification and sediment formation indicating active microbial transformation. The observed decrease in total sulfur content, concurrent sulfate accumulation in the aqueous phase, and process simulations representing dibenzothiophene (DBT) conversion to 2-hydroxybiphenyl (2-HBP) and sulfate were consistent with a sulfur-selective, 4S-like route but did not provide direct genetic confirmation of the canonical 4S pathway. These findings highlight the potential of indigenous Pseudomonas populations for regionally tailored biodesulfurization strategies that can support cleaner fuel production and reduced sulfur emissions in Iraqi Kurdistan, while emphasizing the need for future work on sulfur-free media, resting-cell assays, and characterization of 4S-pathway gene

Drilling activity in the Kurdistan Region of Iraq is challenging because of the swelling behavior, dispersion of particles, and mechanical breakdown of shale, which is subjected to exposure to common water-based drilling fluids (WBDFs). This research examines the role of KCl-based inhibitive-WBDFs through the Gercus, Sarmord, Chia gara, Garagus, Naokelekan (CG-G-N), and Baluti Formations. Inhibitive-WBDFs were developed by mixing several additives in deionized water (DW) along with 1 and 2 wt % KCl, which were subjected to rheological testing, linear swelling measurements (LSM), hot-rolling dispersion, filtrations, and bulk hardness. The results demonstrate that the fluid loss of the drilling fluid containing 2 wt % KCl (WBDF-KCl-2%) used with the Baluti Formation is the lowest compared with other drilling fluids, which are 4.8 and 9 mL for the LPLT and HPHT, respectively. Meanwhile, the Sarmord Formation exhibited the highest filtration rates of 8.5 and 15.9 mL at LPLT and HPHT conditions, respectively. The Gercus Formation, which mostly contains smectite and palygorskite along with a cation exchange capacity (CEC) of 6.5 mequiv/100 g, produced severe swelling of 6.23–6.45% LSM and low bulk hardness of 130–140 psi. Meanwhile, the Baluti Formation, containing the vermiculite and glauconitic clay types with a CEC of 1.75 mequiv/100 g, exhibited the lowest shale swelling rate of 0.16%, 91.51% recovery, and 250 psi bulk hardness when exposed to WBDF-KCl-1%. These results demonstrate that the optimum inhibition depends on fluid formulation, shale mineralogy, and CEC. Although KCl at a low concentration of 1–2 wt% was highly effective in minimizing shale swelling, its role was not universal for all study formations. Thus, it can be stated that the formation response to KCl-based WBDFs affects the inhibition efficiency for swelling prevention, which strongly depends on mineralogy and CEC

This study assesses the feasibility of using high-sulfur residuals from Tawke and Shikhan crude oils as a fuel source for heavy industries. The primary aim was to evaluate its industrial applicability and environmental implications. Petroleum coke, a byproduct obtained via atmospheric and vacuum distillation, was characterized by its high sulfur content, with values ranging from 3.4% for Tawke to 12.5% for Shikhan. Quantitative results from fractional distillation revealed a higher cumulative distillate percentage for Shikhan crude than Tawke, with sulfur mass fractions reaching up to 1.1% for the 290°C distillate fraction in Shikhan oil. Despite its potential as a cost-efficient fuel, high-sulfur petroleum coke presents environmental challenges, particularly due to sulfur dioxide emissions, which could lead to air pollution and acid rain. The findings emphasize that proper emission control technologies and stringent regulatory standards are necessary to mitigate these risks. The study further highlights that the high carbon content and calorific value of this coke make it a viable energy source, but environmental trade-offs must be considered. The novelty of this research lies in its detailed analysis of high-sulfur petroleum coke derived from specific Iraqi crude oils, providing valuable insights for industrial applications in sulfur-rich crude-producing regions. The study contributes to the ongoing discussion about alternative fuels in heavy industries, especially in regions reliant on high-sulfur crude oil reserves.

This study aims to enhance the performance of asphalt mixes by improving the physical characteristics of bitumen across various temperatures. The focus is on the use of innovative modified bitumen to optimize both fundamental and rheological properties. Bituminous binders are tested with varying additive contents (0%, 0.5%, 1%, and 1.5% by binder weight), incorporating iron oxide and zinc oxide nanoparticles (NPs) into Grade (40/60) bitumen. A comprehensive range of testing methods is employed to evaluate the binders, including penetration, ductility, softening point, aging resistance under heat and air exposure, Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR), and direct tension test. The results demonstrate that the addition of iron oxide and zinc oxide NPs significantly alters the physical behavior of the binders, leading to increased viscosity and improved aging resistance. Notably, the modified bitumen shows an increased softening point and decreased penetration and ductility, indicating a hardening effect, while elastic recovery improves with higher additive percentages, enhancing flexibility. These findings provide valuable insights into the modification of asphalt binder and its impact on the performance of asphalt concrete mixtures, particularly in Hot Mix Asphalt (HMA) applications at elevated temperatures, highlighting the novelty of this approach

This study will focus on the Kurdistan region of Iraq. Irrigation is an essential of agriculture, and the process of irrigation takes place by transfer of water from water source to farm. However, energy is the main aspect to consider when carrying out the irrigation process. Due to shortages of electricity and the high cost of diesel, there are difficulties in meeting the demands of irrigation. In this study, solar energy is considered as one way to design a solar water pump that can be used on farms in the Kurdistan region of Iraq. Photovoltaic solar panels have been assessed as a way to provide a successful solar water pump system with a minimum cost. The weather conditions for Duhok city in Kurdistan have been analysed to assess the solar water pump system for local use. The outcome of this study revealed that the solar water pump is applicable and can provide many benefits for the use of clean and renewable energy to transfer water from a water source to farms in the Kurdistan region of Iraq. A proposed design system with cost analysis is provided as an outcome of this study

he current study is performed to identify the flow regimes of oil-gas two-phase flow experimentally in a vertical pipe has an internal diameter of 6.7 cm. It also aims to provide more details about the possibility of using Differential Pressure Transducers (DPT) for indicating flow patterns. A flow development of oil and gas has been investigated in a vertical pipe of 6 m in length and operated at atmospheric pressure. A series of experiments have been run to cover a range of inlet oil superficial velocities from 0.262 to 0.419 m/s, and inlet gas superficial velocities from 0.05 to 4.7 m/s. Wire Mesh Sensors (WMS) have been used to collect the obtained void fraction values of the flow. The Differential Pressure Transducer (DPT) is utilized to measure the pressure drop values of a one-meter along the pipe. The flow patterns are classified according to the analysis of void fractions, pressure gradients regarding time series, tomographic images, probability density functions of the void fractions, and pressure gradients. A bubbly flow is observed at low superficial velocities of gas and liquid, slug flow is observed at the lower flow rate of liquid and moderate flow rates of gas, while the churn flow pattern is recognized at the higher rates of liquid and gas. Also, the result has revealed the possibility of using Differential Pressure Transducers (DPT) to classify the gas-oil flow patterns in vertical pipes

There are many petrochemical industries that need adequate knowledge of multiphase flow phenomena inside pipes. In such industries, measuring the void fraction is considered to be a very challenging task. Thus, various techniques have been used for void fraction measurements. For determining more accurate multiphase flow measurements, this study employed dual non-intrusive techniques, gamma-ray and electrical capacitance sensors. The techniques using such sensors are considered non-intrusive as they do not cause any perturbation of the local structure of the phases’ flow. The first aim of this paper is to analyze both techniques separately for the void fraction data obtained from practical experiments. The second aim is to use both techniques’ data in a neural network model to analyze measurements more efficiently. Accordingly, a new system is configured to combine the two techniques’ data to obtain more precise results than they can individually. The simulations and analyzing procedures were performed using MATLAB. The model shows that using gamma-ray and capacitance-based sensors gives Mean Absolute Errors (MAE) of 3.8% and 2.6%, respectively, while using both techniques gives a lower MAE that is nearly 1%. Consequently, measurements using two techniques have the ability to enhance the multiphase flows’ observation with more accurate features. Such a hybrid measurement system is proposed to be a forward step toward an adaptive observation system within related applications of multiphase flows

Prediction of the flow pattern is a central problms in multi-phase flow analysis. It is a vital point for researchers to accurately predict which flow pattern category types will occur at different flow rates. For this purpose, a mathematical model using the MATLAB (R2017b) computer program is developed for the prediction of gas-liquid two-phase flow patterns in a horizontal pipe with an inner diameter of 30mm under standard conditions. The properties of the air-water two-phase, the pipe geometry, and the flow rates of phases are defined to initiate the operating conditions. The mass flow rates of air and water changed from 0.002 to 0.004 kg/s and 0.672 to 1.334 kg/s, respectively. The impact of properties of the fluid and pipe diameters on two-phase flow configuration is considered to predict the impact of fluid properties on the flow pattern. The findings indicate that as the mass flux increases, the pipe diameters decrease, affecting the configuration of the flow pattern types. The mathematical model’s predicted results are validated by comparing with previous studies. In addition, good agreement is obtained when the predicted results are compared to the ongoing experiment of this research

In an artificial environment, the most important key in the process equipment design is determining gas-liquid two-phase flow frictional pressure drop of pipes. To achieve this, an experimental investigation was carried out in this study to analyze the pressure drops of air-water two-phase flow in a 30mm internal diameter horizontal pipe with a length of 6m at different flow conditions. The study was carried out at 20Co using tap water and air. To cover the slug flow pattern, the volumetric flow rate of water varied from 30 to 80 LPM, and the volumetric flow rate of air from 40 to 200 LPM. Pressure transmitters were used to measure pressure at four different points along the test section, each 2m apart. The results of the experiments were compared to 8 models using 3 distinct methods: Mean Absolute Percentage Error (MAPE), Relative Performance Factor (RPF), and the percentage of data included in the range of the 30% error band. All methods produced similar results, with the Sun- Mishima model being the most accurate.

In an artificial environment, the most important key in the process equipment design is determining gas-liquid two-phase flow frictional pressure drop of pipes. To achieve this, an experimental investigation was carried out in this study to analyze the pressure drops of air-water two-phase flow in a 30mm internal diameter horizontal pipe with a length of 6m at different flow conditions. The study was carried out at 20Co using tap water and air. To cover the slug flow pattern, the volumetric flow rate of water varied from 30 to 80 LPM, and the volumetric flow rate of air from 40 to 200 LPM. Pressure transmitters were used to measure pressure at four different points along the test section, each 2m apart. The results of the experiments were compared to 8 models using 3 distinct methods: Mean Absolute Percentage Error (MAPE), Relative Performance Factor (RPF), and the percentage of data included in the range of the 30% error band. All methods produced similar results, with the Sun-Mishima model being the most accurate

ir-water two-phase flow development in a vertical pipe has been investigated through service of experiments and simulations in this research. Differential Pressure Transducers (DPTs) and Wire Mesh sensors (WMSs) are used to monitor the two-phase flow in a vertical pipe of 67 mm inlet diameter and 7000 mm length. Computational Fluid Dynamic (CFD) is used to evaluate the experiments of the air-water flow in the vertical pipe using a volume of fluid (VOF) model. The operating conditions cover a range of inlet air superficial velocities from 0.05 to 5 m/s. The inlet water superficial velocity remains constant at 0.2m/s and 0.4 m/s for all experiments. The results show that the bubbly flow is noted at low superficial velocities of gas, slug flow is observed at the moderate flow rates of gas, while the churn flow pattern is observed at high rates of gas. There is no significant effect when the Usl changed from 0.2 m/s to 0.4 m/s on the vertical flow lines. Pressure drop is recorded and compared with the CFD simulations. The CFD results are over estimation compared with the experimental pressured drop with maximum absolute error of 21% at Usl of 0.2 m/s and 25% at Usl 0.4 m/s

Suitably formed gas injection geometries permit optimizing the volume of the bubbles created in oil production pipes without recourse to having to change the flow rates of gas. Unfortunately, little research attention has been dedicated to such a study, which may affect the gas lift method of EOR. To address this knowledge gap and to gain more understanding about the coalescence and entrainment processes of the stationary Taylor bubble, an experimental investigation in a bubble drop-down facility using an air–water system was carried out using advanced instrumentation, wire mesh sensor (WMS) and high-speed video photography. The experiments were performed in a 67 mm internal diameter pipe on a stationary Taylor bubble in a downward liquid flow using three different gas injection geometries. Taylor bubble length, the gas and liquid flow rates approaching the stationary bubble were varied. Also, the wake length below, the stationary bubble was measured at different conditions, of gas and liquid superficial velocities and comparisons were made with existing data. A high-speed camera was used to obtain video images of the flow to validate the measurements taken on the wake lengths. Also, the WMS was placed at two different positions, below the gas injection point to obtain time and cross-sectionally resolved information about the spatial distribution of the flowing phases. This information was used to produce time-averaged void fraction, bubble size distribution and contour plots of the two-phase flow structure. Probability density function (PDF) of void fraction of the wake section of the stationary bubbles showed that the flows are in the bubbly flow region whereas the PDF of void fraction for the entire slug unit depicted a typical twin-peaked slug flow. The results of the measurement of Taylor bubble lengths and the corresponding wake of the bubble lengths showed a good match against current published works. The results revealed that the bubble wake length depends on both the nature of the fluid and the pipe diameter, while on the contrary, the bubble length mainly depends on the gas superficial velocity

Radiation-based instruments have been widely used in petrochemical and oil industries to monitor liquid products transported through the same pipeline. Different radioactive gamma-ray emitter sources are typically used as radiation generators in the instruments mentioned above. The idea at the basis of this research is to investigate the use of an X-ray tube rather than a radioisotope source as an X-ray generator: This choice brings some advantages that will be discussed. The study is performed through a Monte Carlo simulation and artificial intelligence. Here, the system is composed of an X-ray tube, a pipe including fluid, and a NaI detector. Two-by-two mixtures of four various oil products with different volume ratios were considered to model the pipe’s interface region. For each combination, the X-ray spectrum was recorded in the detector in all the simulations. The recorded spectra were used for training and testing the multilayer perceptron (MLP) models. After training, MLP neural networks could estimate each oil product’s volume ratio with a mean absolute error of 2.72 which is slightly even better than what was obtained in former studies using radioisotope sources

Abstract-The current research aims to improve the cetane number of diesel extracted from the crude oil of Tawke region- Iraq Kurdistan. A specific mixture of chemical compounds was prepared which included m-nitrophenol, 4-nitro toluene, and nitrobenzene. The components' effects were investigated with regard to the cetane number, flash point, viscosity, and refractive index of diesel. The quantity of each compound mixed with diesel was prepared based on the statistical analysis of the experiment device (Box–Behnken Designs-BBDs). The tested mixture showed a good agreement and improvement of cetane and flash point and a very low effect on viscosity and refractive index. According to the statistical analysis, the main influence on cetane number and the flashpoint was from m-nitrophenol. The investigation showed that the best results were acquired from the samples of 25PPM 4- nitro toluene and 50PPM m-nitrophenol with a cetane number of 65.3. The correlation and the interaction of the regression equation were linear with all cases. It is worth mentioning that all additives positively influenced the cetane number in the regression equation. The sulfur content was measured as well, and the obtained weight percentage of sulfur was 0.8404%.

Two phase flows are of particular importance in various research fields. In the current article, a novel system consists of an X-ray tube and one sodium iodide crystal detector with ability of determining type of flow regime as well as void fraction percentage of a two phase flow, is proposed. MCNP-X code was used for physical modelling of the proposed system and its performance. Radial basis function (RBF) was also implemented for analyzing and classifying the obtained data from the proposed system. Counts in each 1 keV energy bin of photon energy spectra in the detector were inserted in RBF as inputs data set and flow regime and void fraction percentage were obtained as the two outputs. After training the RBF network, the system could simultaneously recognize all the flow regimes and predict the void fraction percentage of a modelled liquid–gas two-phase flow with an acceptable error. The proposed methodology in the present paper has three main novelties and advantages over former studies. Firstly, in this system an X-ray tube is used compared to previous studies where one or more radioisotope sources served as radiation source in a radiation based multi-phase flow meter. Secondly, in former works at least two detectors were used to recognize type of flow pattern and meter volume fractions simultaneously, while in this study only one detector is utilized. Thirdly, in this study just one neural network is used, while in other studies more than one network was used

In this paper, the feasibility of using an X-ray tube instead of radioisotope sources for measuring volume fractions of gas, oil, and water in two typical flow regimes of three-phase flows, namely, annular and stratified, is evaluated. This study’s proposed detection system is composed of an X-ray tube, a 1 inch  1 inch NaI detector, and one Pyrex-glass pipe to model different volume fractions for two flow regimes, annular and stratified. Group method of data handling (GMDH), a powerful regression tool, was also implemented to analyze the obtained data. The obtained results in this work indicate that a simple system based on an X-ray tube and just one NaI detector could be a potential alternative to radioisotope-based systems for separate measurements of gas, oil, and water volume fractions in annular and stratified flow regimes of a three-phase flow

The current investigation aimed to identify pressure gradients and to study the fully developed flow patterns of oil-gas as a blend in a pipe of internal diameter 50 mm and 6 m length with different orientations of 0, 30, and 45-degree. The study was performed at constant values of liquid superficial velocities 0.052, 0.157, 0.262, 0.314, 0.419, and 0.524 m/s, and inlet superficial velocities of gas were ranged from 0.05 to 4.7 m/s at atmospheric pressure. Two pressure transducers located up and downstream were used to measure pressure drops inside the tested pipe. Flow patterns were derived by using the correlation between pressure gradients and time series, the Probability Density Function of differential pressures, pressure gradients with gas superficial velocities, and total pressure losses with mean void fractions. The flow patterns of oil-gas were observed as a uniform stratified flow in the pipe on a 0-degree orientation at various superficial velocities. Stratified, wavy, and slug flow patterns were observed at 30-degree orientation, whereas, bubbly, slug, and churn flow patterns were observed in the pipe of 45-degree orientation. The experiment also showed that pressure drop gradients decreased with increased void fractions, gas superficial velocities, and degree rotations of the flow lines. Finally, the validation of using pressure transducers as a technique for estimating the flow patterns of two-phase flow showed acceptable results with some kind of patterns

Reliable and accurate prediction of the transition from spherical cap bubble to slug flow is crucial not only to the operation of industrial facilities such as the crude oil pipelines, bubble column, and nuclear reactors but also for model development for computational fluid dynamics (CFD) studies. The present paper presents a review of the transition mechanics from spherical cap bubble flow to slug flow in vertical pipes. The bubble flow was split into sub-regions, bubbles and spherical cap bubbles and the mechanisms to classify them (i.e., bubble terminal velocity and cap bubble velocity) was analysed. For now, the literature review does not present some important previous works. This paper presents an original data set of gas–silicone oil in vertical pipes to support the new findings. The experimental two-phase data classifies the flow patterns using the probability density function (PDF) and shows the important flow variables such as average void fraction, pressure gradient, slug body void fraction, liquid slug, Taylor bubble and slug unit lengths, structural velocity and frequency obtained by electrical capacitance tomography (ECT) and a wire mesh sensor (WMS).

The air-water two-phase flow plays an important role in many applications of industry fields. Usually, a 90-degree bend is used to connect pipes for changing the direction of flow which influences the two-phase flow pattern. In this paper, the effect of 90-degree bend under different ranges of gas and liquid superficial velocities on the two-phase flow patterns in the horizontal pipe located after the bend was experimentally investigated, and then results were presented and compared in a two-phaseflow pattern map. Also, tomographic images and probability density functions were used to capture the cross-section void fraction and its distribution for the two-phase flow patterns. The results revealed that at low liquid and gas flow rates, a stratified-wavy flow pattern was observed as a dominant flow pattern. While the wavy-annular and semiannular flow patterns were observed at a high range of gas flow rates in the horizontal pipe. The results also showed that at the high range of liquid flow rate, bubbly, plug, slug, stratified-wavy, and wavy-annular flow patterns were observed in the horizontal pipe when the gas flow increased. The tomographic images and probability density functions gave good agreement with the experimental observations and results

A thorough understanding of the behaviour of the transition from plug to slug flow is imperative based on the fact that the transition can trigger an abrupt radial pressure variation. This can bring about major vibrations to the pipeline and also lead to big differences in pressure gradient and wall temperature. Unfortunately, the transition from plug to slug flow is poorly understood due to the scarce availability of experimental data. Furthermore, a considerable amount of research on the transition from plug to slug flow in the literature is based on an air–water system. In this work, the transition behaviour from plug to slug flow in a horizontal pipeline was experimentally investigated using electrical capacitance tomography (ECT). Working fluids are air–silicone oil. The work was carried out over a range of liquid and gas superficial velocities of 0.05–0.47 m/s and 0.05–4.7 m/s, respectively. Wave growth and wave characteristics mechanisms were observed to be responsible for the transition from plug to slug flow based on the obtained experimental results. Both liquid and gas superficial velocities have a major influence also on these mechanisms. The drift flux parameters for the transition from plug to slug flow was determined. A reasonably good agreement was observed from the comparison between present experimental data against hitherto published empirical models and correlations

The present study has been carried out to investigate the characterization of two-phase flow bubbles that occurred in a column of an internal diameter 50 mm, where the liquid phase is represented in Silicone oil. The effectiveness of the tomography technique regarding the flow patterns analysis is studied as well as, high-speed videos were captured and used in the study. The void fractions of the time series were obtained at different flow rates were considered, and the results were analyzed also by using Probability Density Functions (PDF), film thickness, velocity structure, and Power Spectrum Density (PSD). To obtain the structure velocity, two tomography capacitance sensors were utilized so as to do cross-correlation, besides, the obtained videos were considered also to show the different bubble characteristics. A comparison was assessed between the previously available works of literature with the present study to evaluate the results. It was observed from the obtained tomography images that the flow was in the slug flow region explained by the presence of large bullet-shaped bubbles and the bubble characteristics obtained were comparable to that observed in other viscous liquids. Electrical Capacitance Tomography (ECT) was quite effective in investigating the flow.

The identification and characteristics of flow configurations in pipes are very important in oil industry due to its role in governing equipment design. In vertical riser many flow configurations could be observed such as bubbly, slug, churn, and annular flow. In this project, two tomographic techniques have been applied simultaneously to the flow in vertical riser; an Electrical Capacitance Tomography (ECT) system and Capacitance Wire Mesh Sensor (WMS) system. The pipe diameter employed was 50 mm, investigation of research is carried out between 0.06 - 3.0 m/s for superficial velocities for gas and from 0.06 m/s to 0.4 m/s for oil. Several techniques have been used for analysis output data of two tomography techniques such as Time Series of Cross-Sectional Averaged void fraction, Probability Density Functions (PDF), Image Reconstruction, and Liquid hold up Profile. The averaged void fractions were calculated from the output signal of the two measurements techniques and plotted as function of superficial velocity of gas; from the PDF of the averaged void fraction the flow patterns such as bubbly, slug and churn flows were identified. In addition, it was found that two tomographic techniques are reliable to identify the flow regimes in pipes

New data for pressure drop, void fraction and flow pattern in a vertical riser using air–silicone oil as the system fluid are reported in this work. A differential pressure cell (DP cell) was used to measure the pressure drop. Also, void fraction data were recorded simultaneously by an electrical capacitance tomography (ECT) and wire mesh sensor (WMS). The observed flow patterns are the spherical cap bubble, slug and churn flows. However, only the slug flow without the presence of churn flow is seen within the transition line as predicted by the map. The characteristic probability density function (PDF) derived from void fraction data was used to determine the flow patterns. A comparison between present experimental results and the air–water data reported in the literature was carried out and various levels of agreement were achieved. The PDFs obtained from the DP cell signals for spherical cap bubble and slug flows significantly differ from those derived from the ECT and WMS outputs. Current void fraction and pressure gradient results were compared with the values predicted by ten empirical correlations selected from the literature. Statistical tools such as Mean Square Error (MSE), Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE) were applied in the comparison. The Greskovich and Cooper correlation gave the least MSE, RMSE and MAPE values of 0.0007908, 0.013 and 3.05%, respectively for slug flow

New data for pressure drop, void fraction and flow pattern in a vertical riser using air–silicone oil as the system fluid are reported in this work. A differential pressure cell (DP cell) was used to measure the pressure drop. Also, void fraction data were recorded simultaneously by an electrical capacitance tomography (ECT) and wire mesh sensor (WMS). The observed flow patterns are the spherical cap bubble, slug and churn flows. However, only the slug flow without the presence of churn flow is seen within the transition line as predicted by the map. The characteristic probability density function (PDF) derived from void fraction data was used to determine the flow patterns. A comparison between present experimental results and the air–water data reported in the literature was carried out and various levels of agreement were achieved. The PDFs obtained from the DP cell signals for spherical cap bubble and slug flows significantly differ from those derived from the ECT and WMS outputs. Current void fraction and pressure gradient results were compared with the values predicted by ten In the current study, an experimental study was carried out on the rheological properties of hybrid non-Newtonian nanofluid (MWCNTs–ZnO/Water–Ethylene glycol (80:20 vol.%)) to develop a new model. The viscosities of nanofluid were evaluated in the temperature range of 25–50 °C with volume fractions of φ = 0.075%, 0.15%, 0.3%, 0.6%, 0.9%, and 1.2%. We find that the effect of changes is more obvious when the φ is increased. So the property of non-Newtonian nanofluid is more likely to appear. In addition to a temperature of 25 °C, the viscosity increase from a φ = 0% to 1.2% is higher than 90%, which is very significant. Also, in the maximum φ, at T = 50 °C, 40 °C and 30 °C, the viscosity reduction is 21%, 17%, and 8%, respectively, relative to the reference temperature (25 °C). The above results can be of great help to engineers in designing thermal systems to increase heat transfer and considering pumping power

In the current study, an experimental study was carried out on the rheological properties of hybrid non-Newtonian nanofluid (MWCNTs–ZnO/Water–Ethylene glycol (80:20 vol.%)) to develop a new model. The viscosities of nanofluid were evaluated in the temperature range of 25–50 °C with volume fractions of φ = 0.075%, 0.15%, 0.3%, 0.6%, 0.9%, and 1.2%. We find that the effect of changes is more obvious when the φ is increased. So the property of non-Newtonian nanofluid is more likely to appear. In addition to a temperature of 25 °C, the viscosity increase from a φ = 0% to 1.2% is higher than 90%, which is very significant. Also, in the maximum φ, at T = 50 °C, 40 °C and 30 °C, the viscosity reduction is 21%, 17%, and 8%, respectively, relative to the reference temperature (25 °C). The above results can be of great help to engineers in designing thermal systems to increase heat transfer and considering pumping power

n this study, the sulfur content of crude oil and exported product from Zakho oil fields of Tawke and Qadia, in Kurdistan region of Iraq was studied. The following devices were used; Stanhope-seta (salt in crude oil), centrifuge for Bs&w, Anton par for specific gravity and density, parch method for H2S by nitrogen. Three samples of oil exported abroad were examined and evaluated at a laboratory Institute of fluid dynamics in Germany, for sulfur content and gravity. Several experiments have been conducted to determine the values of sulfur content in oil and some other characteristics related to the above mentioned oils as well as comparing them to global oils and trying to find new and inexpensive ways to reduce and eliminate the sulphur from crude oil.