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Artykuły w czasopismach na temat "SPINNING HUB"
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Makhdum, Farrukh, Alastair Conway i Paul Blackwell. "Experimental Investigation on Shape Evolution in Metal Forming Hybrid Process". Key Engineering Materials 716 (październik 2016): 420–27. http://dx.doi.org/10.4028/www.scientific.net/kem.716.420.
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The feasibility of combining spinning, shear forming and flow forming processes has been demonstrated through manufacturing of a representative of a hub component using industrial scale hybrid-forming machine available at the Advanced Forming Research Centre (AFRC). The manufacturing cycle consisted of single to multiple passes of shear forming, spinning and flow forming. The research has proven that the spinning, shear forming and flow forming can be combined using a single machine with a single set of tooling and single process cycle. Circumferential and axial cracking was observed in initial set of trials which were eliminated using a series of experiments. The methodology that was used in these series of trials to remove the cracks/defects that may occur during forming of such component is presented here.
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Wang, Zhang Feng, Chi Xiang Ou, Meng Jun Wang, Bai Chen Chen i Gang Xian Fan. "Mechanical Properties and Microstructure of A356-T6 Aluminum Alloy Wheel Hub Based on Casting-Spinning Process". Materials Science Forum 1036 (29.06.2021): 3–10. http://dx.doi.org/10.4028/www.scientific.net/msf.1036.3.
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The mechanical properties and microstructure of the A356-T6 wheel hub based on low pressure die casting-hot flow forming process were analyzed by means of optical microscopy (OM), scanning electron microscopy (SEM) and tensile tests. Results showed that the size of the eutectic region and the morphology of the Si phase were the main factors affecting the mechanical properties and fracture morphology of the wheel hub. There was a uniform distribution of eutectic area and fine Si phase morphology in the microstructure of the upper rim and lower rim, moreover, the ultimate tensile strength and yield strength of the upper rim reached 282.4MPa and 185.1MPa, respectively. The fractures were mainly composed of fine quasi-cleavage platform and dimple. The microstructure of the rim showed a long strip along the deformation direction and the eutectic structure and Si particles were uniformly distributed. Irregular polygonal eutectic regions and coarse rod-like Si particles were accumulating in the spoke, causing a serious decrease in mechanical properties, especially in the spoke center and spoke R angle.
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Ūdre, Sandra. "LATGALIAN VOCABULARY AND IDIOMS RELATED TO SPINNING". Via Latgalica, nr 7 (22.03.2016): 125. http://dx.doi.org/10.17770/latg2015.7.1215.
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<em>Spinning (rotation) as a physical phenomenon is an interesting thing. Many archaic notions remain in the language of the dominating perceptions of physical phenomena. Specific studies associated with the Latgalian language have determined that the use of various Latgalian lexemes in contemporary texts creates problems with archaic semantics. These are practical questions for users of Latgalian (primarily writers): which synonym is more appropriate – „doncuot” or „dzyguot” (both meaning ‘to dance’)? Are these terms equivalent? Does the word „maule” (meaning ‘wheel hub’) have only one meaning, even when used in the interjection „ot, maule!”? Why, in Latgalian, does snow spin („snīgs grīž”), but in standard Latvian different words and a different sentence structure must be used for the same expression? This study not only answers these particular questions of lexeme semantics in use, but will also use the linguoculturological approach to discuss the following thematic arcs in Latgalian phraseology and lexicon: 1) signs of natural processes and tools; 2) characteristics of the weather; 3) signs of the process of dancing; 4) lexemes representing the semantics of chaos. An archaic understanding of spinning in language is associated with the concept of the mystic triangle (underworld, world and heaven) model of the world, in which one of the ways to tear down the boundaries between the worlds is to spin in an uncontrollably fast spiral vortex. This notion is reminiscent of Stephen Hawking’s theory of singularity in black holes.</em>
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Sundaram, Maruthachalam, Mouttouvelou Anand, Jaganathan Chelladurai, Paramasivam Varunraj, Sam Joshua Smith, Shubham Sharma, Mamdouh El Haj Assad i Reza Alayi. "Design and FEM Analysis of High-Torque Power Density Permanent Magnet Synchronous Motor (PMSM) for Two-Wheeler E-Vehicle Applications". International Transactions on Electrical Energy Systems 2022 (25.07.2022): 1–14. http://dx.doi.org/10.1155/2022/1217250.
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Launch of electric vehicles have seen a substantial rise for the past few years in emerging economies like India. In countries like India, the growth and penetration of the electric vehicles in the Indian automotive industry specifically for the two-wheeler segments are driven by the demand surge where cost and motor metrics have a substantial deciding factor. The in-wheel hub-motor, which is the prime mover for the two wheelers, decides the comfort zone of the customer in various metrics such as efficiency, torque, speed range, charging, and hence the distance covered. This paper addresses the design formulation of achieving a high torque Permanent Magnet Synchronous Motor (PMSM) conventionally known as the hub-motor, explicitly for electric two-wheeler application. The hub-motor is aimed for the defined D and L (280 × 30 mm) of volumetric constraints to deliver the rated torque of 50 Nm at the spinning speed of 400 rpm. The hub-motor design is aimed for distance range of 108 km/charge, at the vehicle speed of 54 km/hr for the designed diametric and volumetric constraints. This will lead to a typical cost-effective e-vehicle system since the required distance range of 108 km is achievable at the defined rim size and geometry with an enhanced efficiency greater than 90%. The design is carried out by Finite Element Analysis (FEA) using the electromagnetic software MotorSolve. The results computed are analyzed and validated for the optimal loading conditions for the ambient temperature of 50°C. The results confirm the effectiveness of the proposed design formulation and methodology for achieving the high power density hub-motors for satisfying the customer’s comfort zone in establishing the performance metrics of the electromagnetic system.
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Zhou, Heng, Hui Li, Jing Liu, Xinlei Guo, Weiguo Wang, Xi Lu i Shengjie Di. "Study on Structure Design of Generator of Flood Discharge Tunnel with Level Swirling Flow". E3S Web of Conferences 276 (2021): 02013. http://dx.doi.org/10.1051/e3sconf/202127602013.
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Through the design of the Generator of the spillway tunnel, the safe operation efficiency of flood discharge tunnel with the level swirling flow is further improved. This paper takes the horizontal swirl spillway tunnel of Gongboxia Hydropower Station on the Yellow River as an example. First, the project hub facilities of the Gongboxia Hydropower Station are introduced. Moreover, the design of the gradient section and the spinning chamber section in the Generator is also studied. Based on the calculation scheme of structural mechanics, the internal force of the structure under various load combinations such as external water pressure and internal water pressure is calculated. According to Design Codes For Hydraulic Concrete Structure, the structural reinforcement is computed. These provide the basis for the design of the flood discharge tunnel with level swirling flow of large hydropower engineering facilities in Northwest China.
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Usubamatov, R., i T. Zhumaev. "Inertial Forces Acting on a Propeller of Aircraft". Open Aerospace Engineering Journal 7, nr 1 (29.08.2018): 1–13. http://dx.doi.org/10.2174/1874146001807010001.
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Background:Aerospace vehicles use propellers with the different design that possess gyroscopic properties. Recent investigations in the area of gyroscope theory have demonstrated that the gyroscope properties are based on the action of the centrifugal, common inertial, and Coriolis forces of the distributed mass elements of the spinning rotor, as well as the change in the angular momentum.Objective:The combined action of the interrelated inertial forces on the propellers presents the interests for the design of the blades. The objective of the manuscript is the derivation of mathematical models for the inertial torques acting on the spinning propellers that enable computing the stresses of the blades and increasing their reliability.Method:The inertial torques generated by the masses of the rotating blades acting on the propellers are represented by mathematical models in L. Euler’s form.Results:The inertial torques are generated by the several inertial forces of the propeller’s blades and hub and manifested the fluctuation of the variable resistance and precession torques acting around different axes of the propeller. Derived mathematical models for the inertial torques are new and should be used for the computing forces and stresses acting on the propellers of the aircraft.Conclusion:The mathematical models for the torques acting on the propellers consider the several inertial forces of the rotating masses that manifest their gyroscope properties. Derived mathematical models for inertial torques enable for computing the stresses of the aircraft propellers and clearly demonstrate the physical principles and origin of the acting inertial forces.
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Perederiy, V. G., B. G. Gasanov i A. A. Aganov. "Structurization and Properties of Magnetoplastics Made of Mechanically Activated Amorphous-Crystalline Powder Alloys Based on the Nd-Fe-B System". Solid State Phenomena 284 (październik 2018): 455–59. http://dx.doi.org/10.4028/www.scientific.net/ssp.284.455.
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The influence of the method of melt spinning on the basis of the Fe-Nd-B system on the amorphous-crystal structure of ribbons and flakes is shown. It is established that the magnetic properties of magnetoplasts depend on the powders particle size, the parameters of mechanic activation during flake milling, the kinetics of formation and growth of Fe2Nd14B phase nuclei at all stages of their preparation and processing, etc. Isotropic and anisotropic magnetoplasts and sintered magnets with magnetic properties: Br = 0.5-1.25 T, HcB = 180-700 kA/m; (BH)max = 50-280 kJ/m3.
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Truong, Nguyen Xuan, i Nguyen Van Vuong. "Magnetic field assisted melt–spinning Nd-Fe-B ribbons and anisotropic bonded NdFeB magnets prepared thereof". Communications in Physics 26, nr 1 (14.04.2016): 59. http://dx.doi.org/10.15625/0868-3166/26/1/7686.
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The magnetic-field-assisted melt-spinning (FAMS) Nd10.5Fe72Co11B6.5 ribbons were spun in an external magnetic field of 3 kG. The prepared ribbons were ball-milled in xylene solvent for 30 minutes followed by adding in and mixing with the high-temperature binder HTB-1 (3 wt%) for further 10 minutes. The mixed powder was dried and in-mold aligned in a magnetic field of 18 kOe and hot-compacted at 200 oC. The parameters of the FAMS ribbon preparation, ball-milling process, hot-compaction and anisotropic bonded magnets’ fabrication were optimized leading to the magnet’s energy product (BH)max of 10 MGOe. The microstructure and magnetic properties of prepared ribbons and bonded magnets will be discussed in details.
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Nagy, Roland, Réka Kothencz, Máté Hartyányi i László Bartha. "Relationship between Some Colloidal Properties of Non-Ionic-Anionic Surfactant Mixtures". Processes 10, nr 6 (6.06.2022): 1136. http://dx.doi.org/10.3390/pr10061136.
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Non-ionic surfactants are compatible with different types of materials, therefore they can be applied in various packages. Fatty-acid derivates as non-ionic surfactants and their mixtures were investigated to study their colloidal behavior. The HLB value, the particle size, the emulsification capacity and the interfacial tension of various commercial, non-ionic surfactants, and their mixtures with sodium lauryl-ether-sulfate (SLES), were determined. The surfactant mixtures were prepared in different non-ionic: anionic surfactant ratios to examine their effect on several surfactant characteristics. The interfacial tension between the oil phase and aqueous phase was measured using the spinning drop method and the average hydrodynamic diameter of surfactants in the aqueous solution was determined using the dynamic light scattering method. The relationship between various colloidal properties of surfactants was investigated. It was found that there is a significant relationship between the colloidal characteristics and the structure of surfactants that can contribute to their efficient selection method.
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Chu, Fang-Yi, Shannon C. Haley i Alexandra Zidovska. "On the origin of shape fluctuations of the cell nucleus". Proceedings of the National Academy of Sciences 114, nr 39 (12.09.2017): 10338–43. http://dx.doi.org/10.1073/pnas.1702226114.
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The nuclear envelope (NE) presents a physical boundary between the cytoplasm and the nucleoplasm, sandwiched in between two highly active systems inside the cell: cytoskeleton and chromatin. NE defines the shape and size of the cell nucleus, which increases during the cell cycle, accommodating for chromosome decondensation followed by genome duplication. In this work, we study nuclear shape fluctuations at short time scales of seconds in human cells. Using spinning disk confocal microscopy, we observe fast fluctuations of the NE, visualized by fluorescently labeled lamin A, and of the chromatin globule surface (CGS) underneath the NE, visualized by fluorescently labeled histone H2B. Our findings reveal that fluctuation amplitudes of both CGS and NE monotonously decrease during the cell cycle, serving as a reliable cell cycle stage indicator. Remarkably, we find that, while CGS and NE typically fluctuate in phase, they do exhibit localized regions of out-of-phase motion, which lead to separation of NE and CGS. To explore the mechanism behind these shape fluctuations, we use biochemical perturbations. We find the shape fluctuations of CGS and NE to be both thermally and actively driven, the latter caused by forces from chromatin and cytoskeleton. Such undulations might affect gene regulation as well as contribute to the anomalously high rates of nuclear transport by, e.g., stirring of molecules next to NE, or increasing flux of molecules through the nuclear pores.
Rozprawy doktorskie na temat "SPINNING HUB"
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KUMAR, RISHIR. "COMPUTATIONAL ANALYSIS OF AN ECCENTRIC ROTOR THROUGH BONDGRAPH". Thesis, 2017. http://dspace.dtu.ac.in:8080/jspui/handle/repository/15949.
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The computational analysis of an eccentric rotor is based on the bondgraph approach where
the eccentricity of the rotor is analysed using bondgraph. This approach is used in this
experiment to justify the displacements in shaft rotation which is occurring due to
eccentricity introduced in the shaft. The computational analysis is necessary because by
getting these results, a graph can be plotted which will give an accurate result of the
bondgraph approach and it can be seen that by how much the displacement is occurring
when the eccentricity is increased.
The modelling technique used in this approach introduces two shafts connected through a
hub and is provided rotor excitation by connecting it through an external source that rotates
it at different angular velocities. The shafts are connected in such a manner that it has
displacements in radial axis and the displacement is noted.
The bond graph modelling of shaft and spinning hub is done using symbol sonata software
bond pad. Simulation of this model has been carried out on Symbols sonata software which
uses the fourth order Runge-Kutta method. The variation in the position of centre mass of
rotor with change in various parameters such as speed, clearance is observed. The data
obtained is used to get plots.
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Shiu, Feng-Ming, i 許峰銘. "The Analysis of Spinning Forming of Automobile’s Hub form 6061 Aluminum Alloy Billet". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/v4438f.
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碩士國立虎尾科技大學
創意工程與精密科技研究所
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Hub is one of the important parts in the vehicle; it supports the vehicle weight, appearance, such an important role in steering and driving. As the automobile industry a tendency towards eco-car, comfort, safety, and energy saving which meaning the light weight design of automobile is more important. The wheel hub has a direct impact on the performance of the car''s lifetime, appearance, safety and comfort. The advantages of aluminum alloy wheels which is elegantly、highly strength, better heat dissipation, nature lightly, safely function and highly changeable external, less recycling cost all can drop the automobile oil consumption off. As the melting point is low which is easy to integrate all of the parts in the one and cover the parts quantities. It can reduce the automotive research and development and manufacturing cost. In view of the various factors, the aluminum alloy wheels have gradually replaced steel wheels. It symbolizes the high quality and also it’s widely used in the automotive industry. Spinning forming process is a complex process for an advanced manufacturing technology that has gradually applied to manufacture and produce in the automobile hub. To study and assay the spin forming process on the wheel which establishes a realistic mechanical model. To simulate the spin process which using DEFORM-3D to analysis aluminum alloy material of 6061. To analyze the variable area according to the metal flowing and plastic forming in spin process of the stress distribution. The reference data in accordance with taking shape and optimization of processing effectively.
Książki na temat "SPINNING HUB"
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Yunnan wu zhi wen hua. Yunnan jiao yu chu ban she, 2000.
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Yunnan wu zhi wen hua. Yunnan jiao yu chu ban she, 1996.
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Matt-Eron, Thiess. HBB-Chaos Is Spinning Its Threads: A Journey into the Mysterious Experiences of Life. Independently Published, 2019.
Znajdź pełny tekst źródłaCzęści książek na temat "SPINNING HUB"
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Mayer, David. "Quo vadis on the Stage". W The Novel of Neronian Rome and its Multimedial Transformations, 107–22. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198867531.003.0007.
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In contrast to the applause and attendance figures generated by the several film adaptations which followed from 1913, theatrical renderings of Quo vadis were ridiculed, and stage runs were conspicuously brief. Theatre was not able to realise the strongly physical episodes the novelist had imagined and that motion pictures could supply. Although posters advertising the play depicted Lygia’s ordeal in the arena and her rescue by the strong-man Ursus grappling with a maddened aurochs, this crucial ‘sensation scene’ was never brought before theatre audiences. At best, stage versions of Quo vadis were disappointing, at worst they were dismal failures. On the English-speaking stage, three separate iterations of Quo vadis, not adapted until 1900, followed Wilson Barrett’s 1895 play The Sign of the Cross by five years and followed William Young’s theatrical version of Ben-Hur by a year. It wasn’t merely that these earlier plays had consumed the oxygen that might have given life to Quo vadis, it was also that stage versions of Quo vadis relied on similar configurations of characters found in The Sign of the Cross, of Christian-Pagan conflict, and of plots of martyrdom at the whims of despotic Roman emperors and their lubricious wives. Even Wilson Barrett’s adaptation failed to generate much enthusiasm and was readily replaced by his money-spinning biblical dramas and toga-plays. This study will consider adaptations by Jeanette L. Gilder, by Stanislav Stange, and Wilson Barrett. It will account for more successful stage versions of the novel performed in the Roman Catholic countries Italy and France.
Streszczenia konferencji na temat "SPINNING HUB"
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Chen, Siyuan, Xuedao Shu, Yujie Lu i Jiabin Zheng. "Effect of Spinning Process Parameters on Roundness of Aluminum Alloy Wheel Hub Surface and Analysis of Springback Characteristics". W ASME 2022 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/imece2022-94263.
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Abstract This paper mainly studies the effect of process parameters on the roundness of the outer surface of the wheel hub during the spinning process of the forged and Spinned aluminum alloy wheel hub and summarizes the laws of the spring back phenomenon. Firstly, based on the finite element analysis platform of Simufact. Forming, the finite element simulation model of the spinning and forming of 6061 aluminum alloy wheel hub was established in this paper. Then, the spinning process of the 6061 aluminum alloy wheel hub was numerically simulated by using simulation software. Four main process parameters (temperature, feed rate, thinning rate, spindle speed) were selected for the single factor simulation analysis of four factors and five levels. The results show that the optimum process parameters are that the spindle speed is 400 r/min, the temperature is 400 °C, the feed rate is 0.75 mm/r and the thinning rate is 40%. The influence of process parameters on roundness error is as follows: feed rate > thinning rate > spindle speed > temperature. The influence of process parameters on spring-back of 6061 aluminum alloy wheel hub is as follows: thinning rate > feed rate > temperature > spindle speed. The factor that has a greater influence on the fluctuation of spring back is as follows: roller feed rate > thinning rate.
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Politis, E. S., K. C. Giannakoglou i K. D. Papailiou. "High-Speed Flow in an Annular Cascade With Tip Clearance: Numerical Investigation". W ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-247.
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The high-speed flow in an annular cascade with two tip clearance sizes is numerically modeled using a Navier-Stokes solver and the high-Reynolds-number k-ε turbulence model. The numerical predictions should be regarded as complementary to the experimental work conducted in the NTUA annular cascade facility, designed for studying tip-clearance effects in compressor cascades. In the numerically simulated experiment, the stationary blades are mounted on the casing and the tip clearance is formed between them and the spinning hub. The purpose of the present paper is to scrutinize flow trends identified during the measurements and elucidate the flow patterns in the blade passage for rotating and stationary hub.
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Min, Byung-Young, Kalki Sharma, Charles Berezin, Peter Lorber i Brian Wake. "Coaxial Hub Drag Correlation With Water-Tunnel Model Using Two Flow Solvers". W Vertical Flight Society 79th Annual Forum & Technology Display. The Vertical Flight Society, 2023. http://dx.doi.org/10.4050/f-0079-2023-17987.
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Current paper summarizes a correlation study of two flow solvers (CREATE-AV™ Helios and STAR-CCM+), routinely used at Sikorsky, with the spinning coaxial hub drag and flow field measurements conducted by Penn State University at the 12' diameter water tunnel. The Helios modeling approach was aiming for a high fidelity accurate simulation, whereas the STAR-CCM+ modeling approach was aiming for a fast turn-around time with reasonable solution accuracy with a relatively coarse mesh and simplification. The two solvers generally agreed well with the test data within reasonable accuracy and captured the drag trend between two shaft fairing configurations. Impact of turbulence model selection (Spalart-Allmaras Detached Eddy Simulation and Spalart-Allmaras Reynolds-Averaged-Navier-Stokes model) has been demonstrated. The RANS model generally delayed separation and resulted in lower drag. The STAR-CCM+ runs simulated both air and water at matching Reynolds number and showed good agreement between the drag results for the two mediums. Also, the importance of accurate representation of geometric details including gaps, shafts, and holes is highlighted.
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Buchwald, Patrick, Damian M. Vogt, Julien Grilliat, Wolfgang Laufer, Michael B. Schmitz, Andreas Lucius i Marc Schneider. "Aeroacoustic Analysis of Low-Speed Axial Fans With Different Rotational Speeds in the Design Point". W ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gt2017-64417.
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One of the main design decisions in the development of low-speed axial fans is the right choice of the blade loading versus rotational speed, since a target pressure rise could either be achieved with a slow spinning fan and high blade loading or a fast spinning fan with less flow turning in the blade passages. Both the blade loading and the fan speed have an influence on the fan performance and the fan acoustics and there is a need to find the optimum choice in order to maximize efficiency while minimizing noise emissions. The present paper addresses this problem by investigating five different fans with the same pressure rise but different rotational speeds in the design point. In the first part of the numerical study, the fan design is described and steady-state Reynolds-averaged Navier-Stokes (RANS) simulations are conducted in order to identify the performance of the fans in the design point and in off-design conditions. The investigations show the existence of an optimum in rotational speed regarding fan efficiency and identify a flow separation on the hub causing a deflection of the outflow in radial direction as the main loss source for slow spinning fans with high blade loadings. Subsequently, Large Eddy Simulations (LES) along with the acoustic analogy of Ffowcs Williams and Hawkings (FW-H) are performed in the design point to identify the main noise sources and to determine the far-field acoustics. The identification of the noise sources within the fans in the near-field is performed with the help of the power spectral density of the pressure. In the far-field, the sound power level is computed using different parts of the fan surface as FW-H sources. Both methods show the same trends regarding noise emissions and allow for a localization of the noise sources. The flow separation on the hub is one of the main noise sources along with the tip vortex with an increase in its strength towards lower rotational speeds and higher loading. Furthermore, a horseshoe vortex detaching from the rotor leading edge and impinging on the pressure side as well as the turbulent boundary layer on the suction side represent significant noise sources. In the present investigation, the maximum in efficiency coincides with the minimum in noise emissions.
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Hurfar, C. Mandanna, Michael Bartelt i Joerg R. Seume. "A Scaling Method for Modal Sound Propagation in Annular Ducts". W ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-42839.
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The interaction between stationary and rotating components is a major source of the noise emission of aircraft engines. Within the engine, the generated sound propagates in discrete pressure patterns, so-called spinning modes. In order to develop noise reduction technologies for these acoustic components, numerical as well as experimental investigations are carried out. In many cases however, the test rigs are geometrically and thermodynamically scaled in comparison to the turbomachines used in aircraft engines. The objective of this paper is to provide an analytical method to investigate the effect of scaling on the major properties of modal sound propagation in symmetric hard-walled annular ducts with a superimposed uniform axial flow. The potential of generating similar sound propagation properties in two ducts is assessed. For these purposes, the magnitude of the dominating modal group velocity vector, the corresponding axial component, and the angle relative to the duct axis are expressed in terms of the dimensionless parameters Mach number, Helmholtz number, and hub-to-tip ratio. In addition, the corresponding quantities of the wave vector are considered. With respect to these properties, it is shown that for a constant hub-to-tip ratio, modal sound propagation in two annular ducts is similar if the Mach number and Helmholtz number are identical.
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Wartenberg, Nicolas, Dylan Blaizot, Matthieu Mascle, Aurélie Mouret i David Rousseau. "Towards More Representative Workflows for Designing Robust Surfactant EOR Formulations". W SPE Improved Oil Recovery Conference. SPE, 2022. http://dx.doi.org/10.2118/209361-ms.
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Abstract Designing robust EOR surfactant formulations implies performing a number of experiments related to the impact of variable parameters such as injection brine composition and reservoir temperature from near wellbore to in-depth zones. Performance evaluation assays are commonly employed in parametric studies, ahead of the time-consuming coreflood tests. Phase diagram in tubes and spinning drop tests are commonly used, but they do not easily allow deriving representative values of the o/w IFT and can lead to contradictory outcomes. In this work, we addressed the crucial question of the methods implemented to estimate the IFT in bulk tests and we investigated a model case where the robustness of a surfactant formulation was assessed versus temperature. In the first part, we compared, at optimal salinity, the IFT as classically evaluated by the Huh relationship in tubes to the IFT as determined in a spinning drop tensiometer between, respectively, the microemulsion and the water and oil phases in equilibrated and non-equilibrated situations. In the second part, we evaluated the robustness of a surfactant formulation in terms of IFT versus temperature variation by phase diagrams and spinning drop methods and performed simplified oil recovery coreflood tests, using the CAL-X high throughput device. Results showed that IFT discrepancies up to one order of magnitude exist between the Huh estimation and the spinning drop results as well as between the different strategies for determining the spinning drop IFT. Such discrepancies can be interpreted from a scientific point of view, but they highlight the need to discriminate between the IFT determination methods in view of representativeness regarding the actual oil recovery mechanisms in the reservoir. The tests campaign for the temperature robustness, performed in the 40-90°C temperature range, showed, again, discrepancies between the two bulk methods. Namely, Winsor III situation was observed from 60°C to 90°C in the phase diagrams with an optimum at 70°C whereas ultra-low IFT was observed only at 60°C in the spinning drop tests. The coreflood tests revealed that very good oil recoveries were achieved from 40°C to 90°C, with evidence of formation of oil banks leading to final oil saturation as low as 5% only from 60°C to 90°C. These outcomes suggest that, for cases where the various phases are clearly distinguishable in tubes, phase diagrams should be selected as preferred bulk assays. However, these tests provide only coarse estimates of the IFT, which makes performance prediction based on capillary desaturation curves challenging. For this reason, high throughput coreflood tests could also be included in surfactant formulation design workflows to better forecast for the formulation performances.