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By introducing a multiphase twin screw pump as an artificial lifting device inside the well tubing (downhole) for wet gas compression application; i.e. gas volume fraction (GVF) higher than 95%, the unproductive or commercially unattractive gas wells can be revived and made commercially productive once again. Above strategy provides energy industry with an invaluable option to significantly reduce greenhouse gas emissions by reviving gas production from already existing infrastructure thereby reducing new exploratory and development efforts. At the same time above strategy enables energy industry to meet society’s demand for affordable energy throughout the critical energy transition from predominantly fossil fuels based resources to hybrid energy system of renewables and gas. This paper summarizes the research activities related to the applications involving multiphase twin screw pump for gas volume fraction (GVF) higher than 95% and outlines the opportunity that this new frontier of multiphase fluid research provides. By developing an understanding and quantifying the factors that influence volumetric efficiency of the multiphase twin screw pump, the novel concept of productivity improvement by a downhole wet gas compression using above technology can be made practicable and commercially more attractive than other production improvement strategies available today. Review and evaluation of the results of mathematical and experimental models for multiphase twin screw pump for applications with GVF of more than 95% has provided valuable insights in to multiphase physics in the gap leakage domains of pump and this increases confidence that novel theoretical concept of downhole wet gas compression using multiphase twin screw pump that is described in this paper, is practically achievable through further research and improvements.

The effects of the wall shear stress on an Electrical Submersible Pump (ESP) was investigated in this paper. A CFD model in ANSYS Fluent was proposed to simulate actual single-phase and two-phase flow. The bottom hole pressure was minimized by utilizing the artificial lift methods. The flowing fluids in pumps and pipes causes shear stress on surface interacting. In multiphase flow application pump damages on head degradation as well as shear stress affects. The K-ω turbulence model and the multiphase Mixture approach with the sliding technique used to solve the Navier-Stokes equation. To study the effects of gas-liquid (air-water) flow on the ESP and the pump handle ability, the rotation speeds were varied while the other parameters were kept constant. The rotation speeds simulated were at 500, 900, 1500, 2000 and 2500 rpm meanwhile the water flow rate and gas flow rate were kept constant with 20 L/min and 1% fraction, respectively. The results obtained show that as the rotation speeds were increased, the less concentration of the bubbles were observed, moreover the wall shear stress (WSS) increases. Although, the wall shear stress in both single-phase and two-phase flow were tend to increase as the blades length increased, however for the single-phase flow the WSS was found higher in all the simulated rotational speeds.

Grid fins are normally placed at the rear end of cruise missiles, rockets and other ballistic devices to control their trajectory especially at the final stage of flight. These fins provided fine control of the pitch, yaw and other lateral movements, allowing for higher stability and accuracy of the cruise missiles. This project investigates computationally the relation between grid fins inner lattice structures dimensionless parameters and the fins aerodynamics drag coefficient. The project gathered data from 12 different fins by varying the parameters of its internal lattice structure such as thickness, width and chord at various angles of attack (0°, 20° and 40°). The freestream was set at a constant speed of 150 m/s that gives Reynolds number > 1.7 x 106 . The results were experimentally compared by using a re-scaled model of a single fin in a sub-sonic wind tunnel, achieving a difference in results of not exceeding 6%. The results obtained that as the width-chord ratio increases, the aerodynamics drag coefficient increases for fixed thickness-width ratio. The results also demonstrated that as the angle of attack increases, the aerodynamics drag increases. The thickness-width ratio has the larger impact on the aerodynamics drag. The results can be used to improve the design of guided cruise missiles.

The supersonic combustion scramjet in the inlet applies the shock waves compression mechanism tosubstitute the actual compressor from a gas turbine engine. The scramjet works with combustion of fuel throughthe air stream in supersonic condition at least with Mach 5. Novel design of a scramjet intake system was madewith variations in the angle of the fins and entrance width. The best combination of diameter and inclinationangle was 1.75 m and 15 degrees, respectively. The findings were able to increase the oblique shock waveinteractions and supplicate effective combustion and reduce pressure losses for the effective application ofscramjet system, which can be significant for aerospace industry.

The purpose of this research is to conduct aerodynamics study and design a hybrid drone system of fixed-wing and multi-copter. The mission of this drone is to measure human body temperature during COVID19 pandemic. The specific aim of the drone is to fly and cover larger industrial areas roughly about 50 km2 with longer flying time than the conventional drone, of about 1.5 hours. The applications of the simulation software such as XFLR5 and ANSYS have a big impact in identifying areas that need to be improved for the drone system. XFLR5 software was used to compare the characteristics of different airfoils with highest lift over drag, L/D ratio. Based on the airfoil selection, it was found that NACA 4412 airfoil produces the highest L/D ratio. The detailed geometry of the drone system includes a fuselage length of 1.9 meters and wingspan of 2 meters. Moreover, 10 sheets of solar panels were placed along the wing for sustainable flight operation to cover wider areas of mission. The structural analysis was done on ANSYS to test the elastic stress, equivalent strain, deformation, factor of safety pressure as well as lift and drag forces under various operational conditions and payloads. The landing gear was analyzed for harsh landing. ANSYS Computational Fluid Dynamics (CFD) was utilized to study the aerodynamics of the drone at different parameters such as the velocities and angles of attack during the operation. This design ensures the stability of the drone during the temperature measurement phase. The best thermal-imaging camera for such purpose would be the Vue Pro R 336, 45° radiometric drone thermal camera with a resolution of 640 x 512 pixels. This camera has the advantage of a permanent continuous out focus that give the ability of taking measurements even if there was changing on the altitude or any kind of vibrations.

Boundary layer separation and vortex formation cause unappealing deterioration of pump pressure head. The purpose of this research paper is to correlate formation of vortices with near-wall shear stresses resulting in a loss of pump pressure head. This phenomenon is observed at the centrifugal pump impeller tip at various flow rates and impeller rotational velocities through CFD (Computational Fluid Dynamic) analysis. This research paper investigates internal flow in a shrouded centrifugal impeller that is modelled under design flow rate conditions using ANSYS Fluent as its simulation bases solving built-in Navier-Stokes equation, and 𝑘 − 𝜔 SST turbulence model under steady conditions. Numerical results revealed an increase in wall shear stresses with increasing flow rate ranging from 314.2 Pa to 595.60 Pa at increments that pulsate per flow rate. Flow characteristics, such as evolution of vortices and flow turbulence enhance wall shear stresses increasing the wall skin-friction remarkably leading towards a loss in pressure head. This paper analyzes the vortices and turbulence in flow structures with regards to their influence upon the impeller performance.

Electrical submersible pumps (ESP) are referred to as a pump classification whose applications are based upon transporting fluids from submersible elevations towards a fixed pipeline. Specific ESP pumps are utilized in offshore oil and gas facilities that are frequently employed in transport of Liquefied Natural Gas (LNG) terminals. Transport of LNG is a multiphase process that causes operational challenges for ESP due to presence of air pockets and air bubbles; presenting difficulties, such as cavitation and degradation to pump components. This performance degradation causes an economic risk to companies as well as a risk to pump performance capabilities, as it will not be able to pump with the same pressure again. Operational references for multiphase flow in ESP are limited; thus, this research paper reports multistage pumping, review of fundamentals, previous experimental as well as modelling work benefitting future literature for a potential solution. Industries consume power to cope up with the losses associated with pumping two-phase fluids causing company’s fortune. Preceding experimental work on single along with multiphase flow illustrate a distinct flow pattern surrounding the area around pump impeller while the pump is in operation. Through experimental observation, four flow patterns were observed and studied when gas was varied at different flow rates. Increasing the intake pressure proved to increase pump performance at two-phase flow. Experimental study of multiphase flow with LNG fluid is expensive; thus, experimental validation is accomplished on a single stage pump with external intervention of air bubbles to simulate LNG vaporization at fixed pressure and temperature difference

This project was based on the principle of designing, simulating and developing an inexpensive, aerodynamically efficient and regular class electric powered RC aircraft. This prototype was designed to have the maximum strength to weight ratio with minimum drag coefficient (and highest lift coefficient). Moreover, all constraints provided by SAE International competition were followed. The investigation was conducted for the complete airplane and for wing optimization. The model was numerically investigated with ANSYS Fluent 16.1 through the SST K-Omega turbulence model at Reynolds number of 360,000. Once the results were obtained, model and result verification were done by wind tunnel test to validate the data. It was concluded that the airplane with 45° winglet has the highest lift force with minimal drag and 45° winglet was further modified with rectangular and triangular vortex generators in order to further enhance its aerodynamic efficiency for a range of Angle of Attacks (AOA).

Wave Energy Converters (WEC) are devices that harvest the different energies that are associated with moving waves, such as kinetic energy and potential energy, and converting them into useful mechanical and electrical energies. Considering that the ocean and sea are covering around 71 percent of the earth, it is unavoidable to consider it as the main source of renewable energy. This report starts with reviewing a few of the most recent WECs. In the analysis section, it shows a device that functions using pistons to run a hydraulic motor, which then runs a generator in a system. The device is further modified by attaching a rotating mass, which is directly connected to a generator. It is a hybrid device using technologies of both the Pelamis and the Penguin. The power output calculated for the system is 177 kW, which is quiet reasonable considering the wave conditions at Fujairah’s sea shore in United Arab Emirates.

Investigating the characteristics of gas–liquid two-phase flow in a centrifugal pump is critical for evaluating pump performance. In this study, a numerical simulation was performed to understand the effects of gas–liquid turbulence formation in the impeller channels on the performance of a single-stage centrifugal pump. The focus was on the inlet gas volume fraction (IGVF) at constant flowrate and constant impeller speed on the flow structure in the impeller and the pressure surging characteristics. The correlation between Reynolds shear stress and turbulent kinetic energy on pump performance is shown by examining pressure, velocity, turbulent kinetic energy, and gas volume fraction (GVF). The model verification is verified using the theoretical pump pressure head determined by the manufacturer, which demonstrated adequate uncertainty (μ

In the oil production industry, emulsification – two immiscible liquids mix together, is unavoidable as crude oil is usually produced together with water from the reservoir. The presence of emulsions brings numerous undesirable effects to the industry; it affects the flow regimes and flow behavior, reduces the quality of crude oil, requires longer retention time in the separation vessels, causes corrosion to the transport system, contaminates catalyst used in the refining process that leads to huge economic losses. So, it is essential to investigate the formation of emulsions and to study the flow behavior in the pipeline so that proper method can be recommended for the control of the effect of emulsions. It is important to remark that the formation of emulsions through flow shear using lab-scale flow rig has been less researched. This leads to the objectives of this study, which are: first, to characterize the formation of water-in-crude oil (W/O) emulsions formed through the constriction in the pipeline; second, to investigate the effects of W/O emulsions to pipeline flow transport; and third, to analyze the roles of turbulent energy in emulsions formation and flow transport in the pipeline system. This research work enables the oil industry to provide a better strategy in treating the emulsification phenomena in the pipeline transportation system. In the industry, optimum conditions can be obtained from the combination of Reynolds number and types of pipeline constriction in order to obtain lowest wall shear stress so that the energy losses during the transportation of crude in the pipeline can be minimized.

The formation of emulsions is undesirable in the oil and gas industry because emulsification brings a number of problems; it affects the flow regimes and flow behavior, reduces the crude oil’s quality, occupies a volume in the pipeline, reduces the mass flow rate, requires longer retention time in the separation vessels, causes corrosion to the transport system, contaminates catalyst used in the refining process and increases operating cost. Yet, this is unavoidable because oil will always be produced together with water from the reservoir and towards the end of the reservoir life, with the increasing amount of water especially if the reservoir is driven by water aquifer. Less attention has been paid to the pipeline flow of water-in-oil (W/O) emulsions. Therefore, one of the attempts of this research work is to investigate the formation of W/O emulsions using a continuous flow loop, where the emulsification process is induced by the flow shear and turbulence effects such as the pipeline constriction disturbance in the flow loop. The experimental part of this research study is conducted using a model lab-scale continuous flow rig with the present of a 90° bend pipeline constriction and Bintulu crude oil is used. The experiments is focusing on studying the flow velocity and the turbulence role in the formation of emulsions by using an ultrasonic velocity profiler (UVP) system. The roles of turbulence in the formation of emulsions can be understood from the UVP study. This will then broadly contribute to the transportation of crude, i.e. with less emulsions formation, as the energy for the formation of emulsions can be controlled accordingly with the understanding on the roles of turbulence activities in the emulsification process.

The outer hard shell that encloses the coconut fruit is known as the coconut shell. It is available in plentiful quantities and utilizes as an energy source throughout the tropical countries worldwide. The current world production of coconut fruits and the availability of its biomass wastes have the potential to generate power for low emissions in different applications. Coconut shells are among the untapped energy source from agricultural residues. Rural small-scale farmers in Nigeria are not familiar with the technological process of utilizing the coconut shells for sustainable biofuel production. Usually, they use the shells for open burning charcoal production and as organic fertilizer. Future sustainable and eco-friendly thermochemical technology like pyrolysis produces the entire three biofuels products (solid, liquid, and gas) based on the biomass type and its availability. The products are in the form of charcoal/biochar, bio-oil, and biogas fuels used as a substitute for fossil fuels. This chapter highlights the potentials of utilizing the coconut shells by the thermochemical conversion method, specifically the pyrolysis method. The major contribution it will generate to the economic and industrial development of the country. Industries have the potentials in contributing to this sector when biomass wastes are utilized as raw materials in industrial applications. The use of biofuel obtained from biomass thermochemical conversion has more advantages over the use of raw biomass, in terms of clean energy and environmental sustainability concerns.

The United Arab Emirates (UAE) is pushing forward with investment in alternative energy sources. The UAE is well-positioned to meet its energy needs and energy projects and the fuel sources in the future. The UAE should go ahead and invest in renewable energy, which is seeking to develop alternative energy sources. Whilst solar energy availability remains essential in the region, the other renewable technologies such as wind and ocean energies are showing promising potential solutions despite many challenges. The addition of sinusoidal leading-edge propeller blades and vortex generators to wind turbines can enhance its aerodynamics performance and produce less wasted energy in the form of noise. The generation of vortex-induced vibration from finite cylinders produces energy at low ocean current speed. This chapter provides discussion and review on the potential of offshore renewable energy in the country including the conceptual novel designs to integrate such applications to the existing offshore facilities to meet the continuous energy demand.

Aircraft engines are a major contributor to the noise level these days. One way of decreasing these levels is by using different shaped nozzles. The main aim of this research is to investigate the noise levels around an aircraft nozzle by including the chevron nozzle. Another aim of the research is to determine whether the changes in noise levels are linked to the velocities produced by the nozzles. The simulation involves analyzing two nozzles, one with V-shaped chevrons and the other with no chevrons. ANSYS CFD Fluent is used as means to simulate the conditions around a nozzle. The results obtained show that the V-shaped chevrons nozzle produced the lesser noise and the greater average velocity. Keeping the noise levels intact not only benefits the engine in a way but also keeps the noise pollution levels to a minimum.

The ability of an Unmanned Aerial Vehicle (UAV) to fly for an extended period of time is an important issue in today's world for various engineering applications. Taking into account a proper design process, a solar-powered aircraft could potentially fly for inordinate amounts of time continuously. The research aims at designing a light-weight solar endurance glider for an increased flight time by implementing vortex generators across the wingspan for improving its aerodynamics performance. The study utilized ANSYS 18.1 K-Omega SST turbulence simulation technique to successfully simulate the glider at different speeds along with various angle of attacks for aerodynamics optimization and ANSYS static structural module to observe the deformations and stresses on the wingspan. The findings show that the glider should be able to maintain a flight time of at least 6 hours with triangular vortex generators, sharklet winglets and 16 solar panels.

Anaerobic digestion (AD) is one of the renewable technologies and a good alternative for the management of livestock manure. The present study focuses on co-digestion of fresh chicken manure (FCM) with corn stover (CS) experiments for biogas production. The objective of this study is to evaluate the effect of corn stover in the production of biogas and methane content by co-digestion. The mixing ratios of co-digestion of FCM with CS were 1:1, 1:2, and 2:1. The total solids for co-digestion were 8% for all ratios. The results showed that the ratio of 2:1 produced the highest biogas yield (46.7 m3/ton of slurry) and 53.2% of methane purity. The pH fluctuated around a range of 5.2 to 7.9 due to different stages of anaerobic digestion as a result of microbe’s activity.

This project focuses on studying the aerodynamic performance on dimpled airfoil for drones or UAVs propeller applications. The aim is to check if dimples will improve the efficiency of the structure by increasing lift to drag ratio and stall angle or decreasing drag force on the airfoil. The surface modification was done by considering the different arrangement and location of dimples at various Reynold numbers. Dimples help in reducing pressure drag when the airfoil is at larger angles of attack, as the angle of attack is increased, the wake formation starts to occur due to boundary layer separation. Dimple effects on the airfoil surface in same manner of what vortex generator does. Both methods aim to produce turbulent boundary layer in which wake area is reduced therefore reducing pressure drag. For the design process, ANSYS FLUENT was used to computationally investigate the effects of using dimples over the airfoil surface of NACA 2412. A comparative study was conducted between a normal airfoil (no dimples) and dimpled-surface airfoil, at different angles of attacks. It has been found that lift to drag ratio was increased by an improvement of 39.9%. It has been found that the flow separation on the NACA 2412 was delayed by the dimples effect. The critical angle of attack, which the stall occurs was also increased.

Renewable energy is becoming more popular due to the increase in the energy demand and decrease in the fossil fuels. Water covers most of the earth surface, and it is the biggest energy carrier in the planet. Tidal power is due to the gravitational pull of celestial bodies mainly the moon and the sun. It can be harvested through tidal range technologies or tidal stream technologies. Tidal range technologies include tidal barrages, artificial tidal lagoons, and dynamic tidal power. Most of these technologies require high head difference and building dams, which are detrimental to the environment. A design has been proposed to use a piston cylinder arrangement where the head difference would only affect the volume flow rate. The pressure of the liquid in the cylinder is limited to the buoyancy force that can be generated. The proposed system was expected to produce about 20 watts of power at a tidal range of 1 m. The system is scalable and can reach high power ratings without destroying the marine life. It was noticed that this design can provide slightly less power than the La Rance barrage, but at steady rate throughout the day, and a total of 31 GW if 10% of the Arabian Gulf was utilized.

Coconut shells are produced in a vast amount around tropical countries that needs to be utilized properly. Thermochemical methods are the main route for converting biomass to charcoal. Percentage of some relative factors in the biomass such as low-density, low caloric value, high ash, SOX, NOX, moisture content, microstructure, and complex elements are its major drawbacks. Nevertheless, no scientific studies were conducted on the carbonization of converting coconut shells to charcoal from local to global scales. Therefore, comprehensive and precise data on its production is limited. To overcome these problems; biomass materials need to be evaluated to assure the suitability of the biomass for the thermochemical process to curtail the yearning of energy demand. For the overall efficiency of the biomass conversion processes into the preference biomass-derived fuel, it is important to understand the physicochemical characteristics of the biomass. The paper aims at understanding the specialties of coconut shell biomass, which is directly used for thermochemical conversion mainly for charcoal production via; chemical structure, energy potential, and morphological analysis. The biomass exhibits a high: density of 412 kg/m3, a calorific value of 19.4 MJ/kg, fixed carbon of 21.8, a volatile matter of 70.8, carbon of 40.1, and low amount moisture of 5.6, and ash of 1.8. EDX and XRF analysis revealed a low amount of complex heavy metals, trace amounts of sulfur, and nitrogen, thus pre-treatment is not required before its utilization, ideal for thermochemical conversion. The coconut shell possesses amorphous and crystalline carbonaceous materials based on the XRD spectrum. The morphology on FESEM images and surface area analysis shows that the coconut shell contains heterogeneous shapes and scales of macro-pores with high surface area and porosity in nature. These essential qualities are suitable for charcoal production, activated carbon, insect repellent, filler, incense sticks, and other applications. Coconut shell possesses remarkable properties such as carbon-rich and environmentally friendly solid fuel to other biomass and coal materials; hence, it is possible to produce alternative energy from coconut shell biomass due to its several characteristics. © 2021 THE AUTHORS

Dol, S. S., Wong, S. F., Wee, S. K., & Lim, J. S. (2018). Experimental Study on the Effects of Water-in-oil Emulsions to Wall Shear Stress in the Pipeline Flow. Journal of Applied Fluid Mechanics, 11(5)., Study on the emulsion formation mechanically and relate the effect of emulsions to the friction or wall shear stress ( w  ) in the pipeline flow has not yet been explored. So, this study aims to understand the emulsions formation mechanically and to discover the effects of water-in-oil emulsions to the pipeline flow transport by relating the effect of emulsions to the wall shear stress or friction of the pipe. In this study, wall shear stress is compared at water cuts from 0% to 40%, Reynolds number that covers laminar (1100 < Re < 1800) and transitional (2400 < Re < 2800) flow regime, pipeline constrictions that consists of gradual and sudden contraction with a contraction ratio of 0.50 and 0.75, respectively as well as along the pipelines. To carry out the experiments, the Ultrasonic Velocity Profiler and a lab-scale flow rig were used. The results show that the maximum wall shear stress happens at 10% water cuts, higher Reynolds number results in lower wall shear stress, pipeline constriction with contraction ratio of 0.75 results in higher wall shear stress than thecontraction ratio of 0.50 and sudden constriction results in higher wall shear stress than the gradual constriction, and wall shear stress increases with the increase in the length of the pipeline downstream the pipeline constriction. In conclusion, pipeline flow with higher Reynolds number and pipeline constriction (which represents the usage of choke valve in the industries) type gradual constriction ratio 0.50 are recommended to be used in the oil and gas industries because this combination results in the lowest wall shear stress.

Emulsification, specifically formation of water-in-oil (W/O) emulsions, is a very common occurrence in the oil and gas industries which tend to occur naturally given the conditions of the industries. However, it is an unwanted phenomenon as it brings numerous harmful effects to the industries. So, this study aims to carry out a study on the characteristics of the W/O emulsions in order to develop a better understanding on the W/O emulsions. Three parameters, namely, water cuts (WC), Reynolds number and pipeline constrictions were studied. For each of the parameters, the region of study is: 0–40% WC; laminar (1100

Rheological and filtration properties of water based muds play vital roles to have a good drilling efficiency in high pressure high temperature (HPHT) environments. However, there are many occasions where controlling the variation of mud properties due to disintegration of additives is barely possible, resulting in stuck pipe, kick incident or even loss of wells. Although there have been many studies in the past indicating the application of nanosilica in improving the flirtation control of water base muds, there are almost no studies on the significant reduction of the yield point which may cause a huge decrease in cutting carrying capacity of muds and rate of penetrations. The aim of this study is to propose an approach to improve the filtration control of water based muds using nanosilica while maintaining the rheology by using a cationic surfactant. The results obtained from zeta potential measurements indicated that bentonite and nanosilica particles are both negatively charged at different ranges of pH, which would result in reduction of the yield point of the mud samples containing nanosilica. This issue was resolved by employing a cationic surfactant and following certain procedures. Filtration tests conducted under LPLT and HPHT conditions indicated that adding modified nanosilica into the mud samples creates a thin and low permeability filter cake without having any negative impacts on the rheology.

This paper computationally studied the strength of wake structures behind a free-oscillating flexible vortex generator (FVG) by computing the circulation around the FVG using Fluid-Structural Interaction (FSI) simulation of RANS (SST) $k-\omega$ model. The amount of circulation found that the vortex generated by the FVG is stronger than those generated by the rigid vortex generator (RVG). This result has demonstrated that the FVG has a better turbulence generation ability compared to the RVG, suggesting improved energy transport for better heat transfer rate or improving aerodynamics performance. In addition., the result of the analysis was used to justify the proposed flow model for stronger turbulence phenomenon. According to the model, the case with greater structural velocity will result in a greater shear or circulation. For this purpose, the structural velocity was computed and the result demonstrates an excellent agreement with the model's prediction. This has further strengthened the reliability of the proposed model.

This project deals with understanding the various steps involved in performing finite element analysis of computational fluid mechanics systems to enhance the aerodynamics performance of the RC plane for SAE competition. The analysis is conducted for the complete airplane and for the wing optimization. Various modifications are applied to the wing and is analyzed first and then the best cases are applied to the whole airplane. The steps include creating a modeling plan, material selection, geometric modeling, model meshing, applying boundary conditions, and obtaining the required results by solving the models. The software used to conduct the finite element analysis is Workbench. Once the results are obtained, model and result verification are done to validate the data. It is concluded that the airplane-45 degrees winglet has the highest lift force with the minimum drag.