Academic literature on the topic 'Polymer sublayer'

The results of the experimental studies of the efficiency of the method of vortex feeding of polymers developed by the authors are presented. The novelty of the device lies in the fact that when the polymer is fed into the boundary layer, the longitudinal velocity and the additional circumferential velocity are reported simultaneously. It has been established that with the introduction of polyethylene oxide solutions into the boundary layer of the model, using the proposed device, a reduction in hydrodynamic resistance by 60% and hydrodynamic noise up to 14 dB were obtained, which indicates the high efficiency of the proposed vortex feed device to reduce resistance and noise. The paper presents a physical model that shows that polymers affect directly the inner region of the boundary layer. This leads to a thickening of the viscous sublayer and a decrease in the intensity of vortex structures in it. As a result, the process of migration of vortices from the viscous sublayer to the outer region of the boundary layer slows down. All this reduces the turbulence of the boundary layer, thereby leading to a decrease in hydrodynamic resistance and noise.

An experimental investigation of a polymer drag reduced flow using state-of-the-art laser-Doppler anemometry in a refractive index-matched pipe flow facility is reported. The measured turbulent stresses deep in the viscous sublayer are analyzed using the tools of invariant theory. It is shown that with higher polymer concentration the anisotropy of the Reynolds stresses increases. This trend is consistent with the trends extracted from DNS data of non-Newtonian fluids yielding different amounts of drag reduction. The interaction between polymer and turbulence is studied by considering local stretching of the molecular structure of a polymer by small-scale turbulent motions in the region very close to the wall. The stretching process is assumed to re-structure turbulence at small scales by forcing these to satisfy local axisymmetry with invariance under rotation about the axis aligned with the main flow. It is shown analytically that kinematic constraints imposed by local axisymmetry farce turbulence near the wall to tend towards the one-component state and when turbulence reaches this limiting state it must be entirely suppressed across the viscous sublayer. Based on this consideration it is suggested that turbulent drag reduction by high polymers resembles the reverse transition process from turbulent to laminar. Theoretical considerations based on the elastic behavior of a polymer and spatial intermittency of turbulence at small scales enabled quantitative estimates to be made for the relaxation time of a polymer and its concentration that ensure maximum drag reduction in turbulent pipe flows, and it is shown that predictions based on these are in very good agreement with available experimental data.

Object and purpose of research. Relationships between friction resistance coefficient and velocity distributions in the turbulent boundary layer of low-concentrated polymer solutions are investigated. These relationships are different from water because in polymer solutions the friction resistance at constant Reynolds numbers is additionally changed with solution concentrations. Materials and methods. The known experimental data on variations of the friction resistance coefficient and the velocity profiles in turbulent flows in circular tubes at changes in polymer solution concentrations. Main results. The general law of coordinated variations in friction resistance coefficient λ and flow velocity profile in the turbulent boundary layer depending on Reynolds number and polymer solution concentration. The flow models are validated, which describe the laws of velocity variations in all characteristic sections of boundary layer: laminar sublayer, buffer and logarithmic flow areas. A new non-dimensional number is introduced, which characterizes the ability of low concentrated water solutions of polymers to reduce the friction resistance. It is called the Toms effect parameter in the work. Conclusion. Results of the investigation will be useful in developing the theoretical methods for estimation of boundary layer characteristics in polymer solutions.

Friction factor of drag-reducing flow with presence of polymers in a rough pipe has been investigated based on the eddy diffusivity model, which shows that the ratio of effective viscosity caused by polymers to kinematic viscosity of fluid should be proportional to the Reynolds number, i.e. u∗R/ν and the proportionality factor depends on polymer's type and concentration. A formula of flow resistance covering all regions from laminar, transitional and fully turbulent flows has been derived, and it is valid in hydraulically smooth, transitional and fully rough regimes. This new formula has been tested against Nikuradse and Virk's experimental data in both Newtonian and non-Newtonian fluid flows. The agreement between the measured and predicted friction factors is satisfactory, indicating that the addition of polymer into Newtonian fluid flow leads to the non-zero effective viscosity and it also thickens the viscous sublayer, subsequently the drag is reduced. The investigation shows that the effect of polymer also changes the velocity at the top of roughness elements. Both experimental data and theoretical predictions indicate that, if same polymer solution is used, the drag reduction (DR) in roughened pipes becomes smaller relative to smooth pipe flows at the same Reynolds number.

Abstract: The regulated release of medication into the patient provided by the patch makes transdermal drug delivery superior to other methods of pharmaceutical administration. The medication instantly enters the bloodstream through the skin. Low concentration in the blood and high concentration on the patch. The usage of polymers is successful in achieving analgesics' sustained release. To evaluate effectiveness, in vitro and in vivo investigations were conducted. Due to the advantages that biodegradable polymers have over other materials in use, there is currently a huge demand for them. A biodegradable preparation of polymer and active ingredient is made for wound healing with a synthetic porous drug-loaded top layer and a spongy collagen sublayer. This method of analgesic delivery is slowly progressing among people and would further require few advancements as it is completely contrast to the conventional forms.

Turbulent drag reduction by dilute addition of high polymers is studied by considering local stretching of the molecular structure of a polymer by small-scale turbulent motions in the region very close to the wall. The stretching process is assumed to restructure turbulence at small scales by forcing these to satisfy local axisymmetry with invariance under rotation about the axis aligned with the main flow. It can be shown analytically that kinematic constraints imposed by local axisymmetry force turbulence near the wall to tend towards the one-component state and when turbulence reaches this limiting state it must be entirely suppressed across the viscous sublayer. For the limiting state of wall turbulence, the statistical dynamics of the turbulent stresses, constructed by combining the two-point correlation technique and invariant theory, suggest that turbulent drag reduction by homogeneously distributed high polymers, cast into the functional space which emphasizes the anisotropy of turbulence, resembles the process of reverse transition from the turbulent state towards the laminar flow state. These findings are supported by results of direct numerical simulations of wall-bounded turbulent flows of Newtonian and non-Newtonian fluids and by experiments carried out, under well-controlled laboratory conditions, in a refractive index-matched pipe flow facility using state-of-the art laser-Doppler anemometry. Theoretical considerations based on the elastic behavior of a polymer and spatial intermittency of turbulence at small scales enabled quantitative estimates to be made for the relaxation time of a polymer and its concentration that ensure maximum drag reduction in turbulent pipe flows, and it is shown that predictions based on these are in very good agreement with available experimental data.

Les besoins d’allègement de poids dans le transport principalement en vue d’une réduction des émissions des gaz à effet de serre placent les composites à renfort de fibres de carbone (CFRC) comme matériaux potentiels. La fonctionnalisation de ces matériaux leur confèrerait une valeur ajoutée et de nouvelles perspectives d’application. La fonctionnalisation des composites CFRC implique de nombreux travaux de recherche qui se heurtent à une problématique de la décohésion du dépôt de surface en raison de la faible adhérence CFRC-dépôt, car les deux parties étant respectivement en polymère et en métal. Ce problème est un verrou scientifique. L’objectif de ce travail de thèse est alors de mettre au point une solution de fonctionnalisation de surface d’un composite CFRC par une technique de métallisation par collision à haute vitesse. Une partie des travaux effectués consiste à développer une structure composite hybride constituée d’une structure CFRC et d’une sous-couche composée d’une phase métallique et d’une phase polymère calibrée pour compatibiliser la structure CFRC et la technique de métallisation par projection à froid.Une partie de ce travail de thèse est consacrée à l’élaboration d’un système hybride CFRC/sous-couche biphasique superficielle en polymère/métal. Le procédé d’infusion sous vide a été mis en œuvre pour la polymérisation de ce système. La sous-couche biphasique consiste en un mélange de poudre micrométrique métallique avec de la résine thermodurcissable (époxy) ou thermoplastique (poly méthacrylate de méthyle) à différentes concentrations, permettant de produire des sous-couches de type TS-Al, TS-Cu, ou TP-Cu directement intégrées à la surface de la structure CFRC. Des essais de métallisation de ces sous-couches par projection à froid ont ensuite été réalisés, en utilisant le système de projection à basse pression Dymet 423. Des poudres de cuivre, d’aluminium, de zinc et d’étain sont choisies comme matériau de métallisation en raison de leur bonne conductivité électrique et thermique. Des poudres composites constituées d’un mélange métal/alumine ont aussi été considérées pour améliorer la formation de revêtement en tirant profit de l’effet de martelage produit par les particules d’alumine. Un revêtement (Sn + Al2O3) d’une épaisseur de 60 µm a été obtenu sur la sous-couche TS-Cu, démontrant en cela la faisabilité d’une métallisation d’une structure CFRC via la sous-couche biphasique, par projection à basse pression.Une autre partie de cette thèse porte sur une analyse phénoménologique de la réponse mécanique de la sous-couche biphasique TS en utilisant la simulation numérique. La collision à haute vitesse endommage la sous-couche à matrice thermodurcissable qui se fragmente sous l’effet de la contrainte de collision. Ce phénomène explique la difficulté de formation de revêtement sur la sous-couche à base de polymère thermodurcissable. Afin d’identifier des matériaux polymères appropriés pour une bonne tenue mécanique de la sous-couche pendant la collision à haute vitesse, une simulation sur des substrats thermoplastiques (TP et TP-Cu) a été étudiée. Les résultats montrent une pénétration des particules de Cu projetées, dans le substrat TP, en formant en cela une adhésion métal/résine par ancrage mécanique. Les particules de Cu constituant la sous-couche permettent de favoriser la déformation plastique des particules de Cu projetées, et ensuite la formation d’un revêtement. Ce constat a permis d’élaborer des essais expérimentaux de projection à froid à haute pression pour métalliser des substrats à base de matrice TP. Il en résulte une formation de revêtement pour différentes poudres (Cu sphérique, Cu dendritique, Cu + Al2O3). Le revêtement obtenu peut atteindre une épaisseur de 95 µm, 231 µm et 114 µm respectivement. Ces résultats démontrent bien la faisabilité d’une métallisation d’une structure CFRC via une sous-couche biphasique TP et une technique additive par projection à froid à haute pression
Carbon fiber reinforced composites (CFRC) have been successfully developed since decades as efficient and lightweight materials for various innovative applications and mostly for transport applications. Due to the low electrical conductivity of the polymer matrix of CFRCs, a better functionalization of such materials, such as developing a metallic coating on the CFRC structure of an aircraft, brings added values that contribute to a longer life and new performances such as the lightning strike protection (LSP) performance. The major objective of this PhD research program is to improve the metallization of a CFRC substrate by a new approach that focuses on the development of a hybrid layered structure made of CFRC and a biphasic sublayer embedded onto the top surface of this structure, prior to a cold spray metallization. To achieve this objective, the research works rely on an experimental task and a computational analysis which can be divided into three significant contributions:The first experimental part focuses on the development of a biphasic sublayer in between the CFRC substrate and the metal coating. This sublayer consists of a mixture of a polymer (Thermoset Epoxy, Thermoplastic Polymethyl methacrylate) with a micron sized metal powder (Al, Cu). The vacuum assisted resin infusion process is used to produce the hybrid CFRC with the biphasic sublayer on its top face. Prior to the cold spray metallization, the thermo-physical properties of the hybrid CFRCs/biphasic sublayer are characterized using a differential scanning calorimetry (DSC) analysis and a thermal conductivity measurement. The mechanical properties of the hybrid CFRC system are characterized by means of mechanical testing (impact test, tensile test, three-point flexural test, lap-shear adhesion test).The second part of this PhD work investigates the metallization of the hybrid system CFRC/biphasic sublayer using the low-pressure cold spray Dymet 423 system. Copper, aluminum, zinc, and tin powders are used as coating material due to their good electrical and thermal conductivity. Powder mixtures made of these metals and alumina powders (Al2O3) are considered as other potential materials for the cold spray metallization of the biphasic sublayer/CFRC system. An embedment of the cold spray powders onto the biphasic sublayer is found to ease the coating formation, except for the Cu cold spray powder. A continuous 60 μm thick coating of Sn+Al2O3 is obtained onto the biphasic TS-Cu sublayer, that shows the feasibility of surface functionalization of CFRC via a biphasic sublayer and a low-pressure cold spraying.The third part of this PhD work focuses on a phenomenological analysis of the mechanical response of the TS biphasic sublayer during the high-speed collision of the cold spray process. This part aims to depict further improvements through a computational analysis. The erosion issue of the epoxy matrix of the sublayer is found to govern the unsuccessful coating formation onto the thermoset sublayer. Therefore, to find out suitable biphasic polymer materials, a simulation of a Cu powder collision onto thermoplastic media (TP and TP-Cu) has been investigated, that shows a good embedment of the Cu powder onto the TP substrate via a mechanical interlocking (metal-to-resin bonding). The copper particles of the biphasic TP-Cu sublayer enable to promote a plastic deformation of the sprayed Cu particles and is conducive to a bonding formation and coating growth. Finally, to provide a proof of concept, experimental HPCS metallization onto biphasic sublayers made of a TP matrix are performed. A continuous coating formation of spherical Cu, dendritic Cu, and Cu+Al2O3 is obtained onto TP-Cu sublayer, with a thickness of 95 µm, 231 µm, and 114 μm respectively. Thereby, the feasibility of the metallization of CFRC via a TP biphasic sublayer and a high-pressure cold spray deposition has been demonstrated

Abstract This study aims to develop a metal-based compatibilizing sublayer on a Carbon Fiber-Reinforced Polymer (CFRP) composite to overcome the erosion issue of polymer substrate using the cold spray deposition technique. The objective is to contribute to the in-situ repair of aircraft structures. Two cases of sublayers, i.e., Al-based sublayer (1126 μm thick) and Cu-based sublayer (547 μm thick), have been prepared and co-cured with the CFRP substrates by pressure assisted molding process. Gas-atomized copper powders were deposited on a reference sample of aluminum panel (A-0) and on two functionalized composite substrates (A-1 and C-1) by a high-pressure cold spraying (HPCS) process. The results show that cold spray deposition onto the Al-based sublayer leads to a coating formation whereas the Cu-based sublayer is strongly eroded by the supersonic collision of copper powders. Scanning electronic microscope (SEM) morphologies were used to investigate the HPCS deposition mechanisms on various configurations of substrates. It was found that the high deposition efficiency of case Cu/A-0 was achieved by metallic bonding, evidenced by the significant flattening powders and agglomeration phenomenon of multiple particles. The copper particles of case Cu/A-1, encapsulated by the deformed aluminum powders, could anchor to the substrate via mechanical interlocking, whereas only pure localized fracture of epoxy and exposed broken carbon fibers were observed on the substrate of case Cu/C-1. The results demonstrated the feasibility of an Al-based sublayer-assisted cold spray process for the thermosetting CFRP composite to achieve a successful deposition of copper powders, which also emphasized the necessity to search an optimal material coupling between sublayers and coatings.

Abstract In order to investigate the potentials to improve the deposition efficiency and to functionalize the polymer-based substrates, six configurations of microparticles Sn, Zn, Al, Sn+Al2O3, Al+Al2O3, Cu+Al2O3 were cold sprayed on the substrate of Carbon Fiber Reinforced Polymer (CFRP) composites equipped with Cu-based sublayer or Al-based sublayer. The process conditions were kept unchanged. Microanalysis of sublayers and coatings was performed via a Scanning Electronic Microscope (SEM), the deposition mechanisms of different powders couplings on CFRP substrate were then discussed. The results indicated that although the deposition efficiencies were negative, the systems of Zn, Al and Al+Al2O3 perform better among all the configurations. It was found that the addition of alumina led to a lower deposition efficiency (DE), compared to the corresponding pure coatings. For single-component Sn, Zn and Al powders, they all showed an increasing trend of DE when changing the substrate from Cu-based systems to Al-based systems. The aim of this present work is to elaborate the intrinsic causes of erosion issues and to provide a reference value for picking spraying materials and preparing functionalized CFRP substrates. According to the SEM analysis, the insufficient deformation and escape behaviours of spherical copper powders explained for the difficulty of coating formation. It was noticeable that the surfaces of Al-based systems were more uniform than those of Cu-based ones, due to their desirable deformation abilities. Besides, the significant flattened particles, material mixing and melting phenomenon were observed in Al-involved systems, which would definitely contribute to the adhesive bonding between coating and substrate.

A class of wall shear stress sensors has been developed. The potential of ionic polymer membrane transducers for measuring skin friction in liquid flows is demonstrated. Ionic polymer transducers are thin polymer membranes that exhibit high sensitivity to mechanical strain, and have been shown to demonstrate sensitivities two orders of magnitude higher in charge-sensing mode than piezoelectric polymers such as PVDF. Thus, they are as sensitive to mechanical strain as piezoelectric ceramics (i.e. PZT) but have the high compliance and durability of a polymer. The application of active ionic polymers in delivering easy to implement, accurate, dynamic measurements of skin friction in harsh environments promises significant advantages over current technologies. In particular, a robust technique for measuring wall shear stress is needed to assess the effectiveness of new friction-reducing techniques, including the use of lubricants and micro-bubble injection within the viscous sublayer. Conventional technologies have been unable to provide sufficiently accurate measurements over a large range of fluid velocity fluctuation scales. Moreover, their implementation can be complicated in the case of non-flush mounting sensors, and their applicability is often limited to forgiving environments. An initial feasibility test was designed with the objective of replicating classic theoretical and experimental skin friction coefficient results for a sharp edge flat plate boundary layer. An ionic polymer and a piezoelectric film (PVDF) were evaluated for Reynolds numbers ranging from the laminar flow regime to fully turbulent flow. The PVDF sensor displayed no discernable response to wall shear. The ionic polymer sensor, however, showed significant response to wall shear and strong correlation with the Reynolds number. In addition, a Stokes oscillating plate apparatus was designed for calibration and testing of the ionic polymer sensor.

Abstract A design concept for potentially hard damage-resistant ceramic coatings on relatively soft substrates is proposed. Such coating structures are of direct relevance to biomechanical structures, especially teeth and dental crowns. In this study failure modes in bilayers and trilayers with relatively hard, brittle coating outerlayers on soft, tough substrate underlayers are evaluated. Coating/substrate systems of interest include ceramic/ceramic, ceramic/metal, and ceramic/polymer. A key element of these structures is a well-bonded interface, to prevent delamination during stressing. The objective is to arrest intrusive coating cracks in a tough sublayer, rather than merely to deflect them along a weak interface.

Polymer drag reduction is investigated using the Particle Image Velocimetry (PIV) technique in fully developed turbulent flow through a horizontal flow loop with concentric annular geometry (inner to outer pipe radius ratio = 0.4). The polymer used was a commercially available partially hydrolyzed polyacrylamide (PHPA). The polymer concentration was varied from 0.07 to 0.12% V/V. The drag reduction is enhanced by increasing polymer concentration until the concentration reaches an optimum value. After that, the drag reduction is decreased with the increasing polymer concentration. Optimum concentration value of PHPA was found to be around 0.1% V/V. Experiments were conducted at solvent Reynolds numbers of 38700, 46700 and 56400. The percent drag reduction was found to be increasing with the increasing Reynolds number. The study was also focused on analyzing the mean flow and turbulence statistics for fully-turbulent flow using the velocity measurements acquired by PIV. Axial mean velocity profile was found to be following the universal wall law close to the wall (i.e., y+ <10), but it deviated from log law results with an increased slope in the logarithmic zone (i.e., y+ >30). In all cases of polymer application, the viscous sublayer (i.e., y+ <10) thickness was found to be higher than that of the water flow. Reynolds shear stress in the core flow region was found to be decreasing with the increase in polymer concentration.

Particle tracking velocimetry has been used to measure the velocity fields of both continuous and dispersed phases, in a microbubble turbulent boundary layer, in a channel flow. Hydrogen and oxygen microbubbles were generated in the flow by electrolysis. The average size of the microbubble radius was 15 μm. Significant drag reductions (above 40%) were observed, when the accumulation of microbubbles took place in a critical zone within the buffer layer. The z-component of the mean vorticity field was derived from the measured velocity fields. There is a decrease in the magnitude of the vorticity, leading to a smother transition from the viscous to the buffer layer. This indicates the increase of the viscous sublayer thickness, as also observed in investigations of drag reduction by polymer and surfactant injection in liquid flows.

The mechanism of drag reduction due to spanwise wall oscillation in a turbulent boundary layer is considered. Published measurements and simulation data are analyzed in light of Stokes’ second problem. A kinematic vorticity reorientation hypothesis of drag reduction is first developed. It is shown that spanwise oscillation seeds the near-wall region with oblique and skewed Stokes vorticity waves. They are attached to the wall and gradually align to the freestream direction away from it. The resulting Stokes’ layer has an attenuated nature compared to its laminar counterpart. The attenuation factor increases in the buffer and viscous sublayer as the wall is approached. The mean velocity profile at the condition of maximum drag reduction is similar to that due to polymer. The final mean state of maximum drag reduction due to turbulence suppression appears to be universal in nature. Finally, it is shown that the proposed kinematic drag reduction hypothesis describes the measurements significantly better than what current Direct Numerical Simulation does.

Abstract Three horizontal wells were drilled and completed with hydraulic fracturing in an explorational environment based on reservoir characterization from openhole logs. Limited success in establishing gas production rates showed the need for an integrated technical workflow to be applied for the next well, well-A. After good production results were achieved in well-A, the next phase used three more wells to correlate the production performance based on precise well placement. In well-A, openhole sampling was done during drilling of the pilot hole prior to sidetracking the lateral. This was followed by a novel fracturing approach with slickwater hybrid, low-polymer, and CO2 foamed treatments to study the effectiveness of treatments. Post-fracturing diagnostics including a production log and spectral noise log (SNL) were performed to assess production by stage. Three more wells were drilled in the same reservoir, and then a synthetic correlation model was built with resistivity logs to correlate precise lateral landing with the prolific sublayer. Finally, the production performance of all wells was studied based on well placement, fracturing, and the completion approach. The first phase of the study of the three wells allowed characterizing well-A in terms of reservoir interval, wellbore orientation, and fracturing strategy. Layer 1 was used to sidetrack the lateral. The post-fracturing production log and SNL indicated the CO2 foamed treatment was the best approach for well-A. The next three wells in the development phase were drilled in layer 1 with good production but inconsistent results. Because the highest flow rate in well-A was seen from the heel part of the lateral, an ultradeep resistivity-correlation bed boundary model was generated from well-A to characterize structural dip, and precise lateral locations were analyzed for all the wells. The model was also used to describe the most prolific sublayer within the layer 1 reservoir. The results showed a strong production dependence on the lateral landing with respect to the defined prolific sublayer. The number of fractures placed also showed a direct relation with gas rates. Finally, a geosteering simulation model was built to be used to further develop the area and detailed recommendations were documented. The ultradeep azimuthal resistivity tool has the capacity to detect ultradeep resistivity up to 100 ft from the borehole. Simultaneously, it can map ultrathin layers, which is necessary for the laminated reservoirs. The objectives of precise well placement and rendering productive gas wells in the exploration area through a comprehensive workflow was optimized and analyzed over 4 years. This paper presents systematic findings and a robust framework ready for implementation in future developments.

Abstract With the expanding offshore rig activity in United Arab Emirates leading to an increased number of horizontal wells and longer drains, coupled with changing rock fabrics, it became imperative to diverge from the existing stimulation methods to deliver more consistent and reliable results. These results were achieved via the introduction of single-phase retarded acid (SPRA) and viscoelastic diverting acid (VEDA) to both active and shut-in wells offshore. The introduction of SPRA and VEDA was possible after extensive laboratory testing including core flow tests, solubility tests, emulsion tendency testing, and corrosion inhibition tests to evaluate and benchmark the performance of these blends in comparison to the existing acid recipes such as plain HCl and polymer-based diverted acid. These tests showed that a combination of SPRA and VEDA would allow maximizing lateral coverage and enhance acid penetration due to the reduced rate of reaction and chemical diversion capabilities from thief zones. Combining the introduction of SPRA and VEDA with a shift to bullheading and higher pumping rates enabled the delivery of previously unachievable production results at sustainable wellhead pressures or even well revival of shut-in wells. In addition, reduction of acid content for dolomite stimulation was possible due to the implementation of acid retardation, which also allowed protecting wellheads from exposure to higher acid concentrations while bullheading. Treatment parameters such as volumes, rates, and acid/diverter sequence and ratio were then adjusted for optimal wormhole penetration across all zones using a new carbonate matrix acidizing modeling software. Post-treatment evaluation for the cases of previously shut-in wells has proven the success of the SPRA and VEDA combination. Shut-in wells that were unable to produce sustainably at the required tubing-head pressure (production flowline pressure), were able to produce sustainably with a 100% increase in production compared to prestimulation testing. Similarly, for gas wells, the combination of SPRA and VEDA resulted in a 50% increase in production at a similar bottomhole pressure. In addition, water injectors have also exhibited sustainably increased levels of injectivity compared to prestimulation levels, leading to better sweepage. The novelty of this paper is the comparison between historical carbonate stimulation results in UAE using plain HCl acid with polymer-based diverted acid and using SPRA with VEDA. It also sheds light on the game-changing solutions that suit the ever-increasing challenges observed in offshore oil and gas wells including well placement, lithology, permeability contrast, and type of hydrocarbon within the various target sublayers.