Thematische Bibliographien / Lower cylinder

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Auswahl der wissenschaftlichen Literatur zum Thema „Lower cylinder“

Autor: Grafiati

Veröffentlicht am 28. Juni 2021

Zuletzt aktualisiert am 3. Februar 2022

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Zeitschriftenartikel zum Thema "Lower cylinder"

Alzaharnah, Iyad T. „Thermal Stresses in Thick Walled Cylinders due to a Periodic Moving Heat Source: Effect of Material Properties“. Advanced Materials Research 445 (Januar 2012): 627–30. http://dx.doi.org/10.4028/www.scientific.net/amr.445.627.

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nternal heating of hollow cylinders with moving periodic heat source is examined in relation to surface treatment applications. This study includes three different cylinder materials, namely aluminum, nickel and titanium. Effective stresses in the cylinder wall are found to be mainly attributed to longitudinal temperature gradients. The aluminum cylinder shows sharper longitudinal temperature gradients as compared to the nickel and the titanium cylinders, which is due to the high value of the aluminum specific heat capacity. However, the larger Eα (elasticity modulus × thermal expansion coefficient) values for nickel cylinder result in higher levels of stress although nickel and titanium cylinders exhibit similar longitudinal temperature profiles. During dwelling time for the heating source at a certain spot, titanium cylinder exhibits lower levels of temperature increase as compared to aluminum and nickel cylinders, due to its lower value of thermal conductivity.

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Willems, Harco. „“Cylinder seals for the lower classes”“. Zeitschrift für Ägyptische Sprache und Altertumskunde 145, Nr. 2 (02.11.2018): 187–204. http://dx.doi.org/10.1515/zaes-2018-0017.

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Summary Egyptologists have paid much attention to inscribed administrative seals and their impressions. By contrast, the so-called figure seals, which render no or hardly any text, but instead use icons and signs inspired on hieroglyphs which however yield no coherent sense, have received far less attention. Usually this material is related to the lower strata of society. According to current interpretations, it is rooted in the Egyptian culture of the later Old Kingdom and First Intermediate Period. The phenomenon would be a corollary of the decreasing prominence of central state authority in this era. Proceeding from a number of recent early Old Kingdom finds from al-Shaykh Saʽīd/Wādī Zabaydā, the present article argues that a) figure seals were continually in use from the late Predynastic until the late Old Kingdom and b) different from what is commonly assumed, stamp seals were in existence long before the late Old Kingdom. The article challenges the relationship between these object categories and developments specifically in late Old Kingdom Egypt.

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Li, Zhihua, Jane H. Davidson und Susan C. Mantell. „Numerical Simulation of Flow Field and Heat Transfer of Streamlined Cylinders in Cross Flow“. Journal of Heat Transfer 128, Nr. 6 (23.12.2005): 564–70. http://dx.doi.org/10.1115/1.2188463.

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The drag and convective heat transfer coefficients along the outer surface of lenticular and elliptical tubes with minor-to-major axis ratios of 0.3, 0.5, and 0.8 were determined numerically for cross-flow Reynolds numbers from 500 to 104. The two-dimensional, unsteady Navier-Stokes equations and energy equation were solved using the finite volume method. Laminar flow was assumed from the front stagnation point up to the point of separation. Turbulent flow in the wake was resolved using the shear stress transport k-ω model. Local heat transfer, pressure and friction coefficients as well as the total drag coefficient and average Nusselt number are presented. The results for streamlined tubes are compared to published data for circular and elliptical cylinders. Drag of the elliptical and lenticular cylinders is similar and lower than a circular cylinder. Drag can be reduced by making the streamlined cylinders more slender. Drag is relatively insensitive to Reynolds number over the range studied. An elliptical cylinder with an axis ratio equal to 0.5 reduces pressure drop by 30–40% compared to that of a circular cylinder. The Nusselt numbers of lenticular and elliptical cylinders are comparable. The average Nusselt number of an elliptical or lenticular cylinder with axis ratio of 0.5 and 0.3 is 15–35% lower than that of a circular cylinder.

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Wailanduw, A. Grummy, Triyogi Yuwono und Wawan Aries Widodo. „Flow Characteristics around Four Circular Cylinders in Equispaced Arrangement near a Plane Wall“. Applied Mechanics and Materials 493 (Januar 2014): 245–50. http://dx.doi.org/10.4028/www.scientific.net/amm.493.245.

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The flow characteristics around four circular cylinders in equispaced arrangement located near a plane wall were investigated experimentally. The pressure distributions on the each cylinder surface and on the plane wall were measured for a spacing ratio L/D= 1.5 (L, center to center spacing between cylinders; D, diameter) and G/D= 0.2 (G, gap spacing between cylinder surface and the plane wall) in a uniform flow at a Reynolds Number of 5.3 x 104. The 2D U-RANS numerical simulation with k-ω SST as viscous model was used to visualize the flow phenomena occured around the cylinders. The results showed that the flow tend to be biased on the upper side of cylinders configuration. It causes the stagnation at the upstream cylinders occured at lower side of cylinders and results a formation of a narrower wake behind the third cylinder and a wider wake behind the fourth cylinder.Keywords: equispaced arrangement, circular cylinders, plane wall

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Qin, Bin, Md Mahbub Alam und Yu Zhou. „Free vibrations of two tandem elastically mounted cylinders in crossflow“. Journal of Fluid Mechanics 861 (21.12.2018): 349–81. http://dx.doi.org/10.1017/jfm.2018.913.

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The paper presents an experimental investigation on the flow-induced vibrations of two tandem circular cylinders for spacing ratio $L/D=1.2{-}6.0$ and reduced velocity $U_{r}=3.8{-}47.8$, where $L$ is the cylinder centre-to-centre spacing and $D$ is the cylinder diameter. Both cylinders are allowed to vibrate only laterally. Extensive measurements are conducted to capture the cylinder vibration and frequency responses, surface pressures, shedding frequencies and flow fields using laser vibrometer, hotwire, pressure scanner and PIV techniques. Four vibration regimes are identified based on the characteristics and generation mechanisms of the cylinder galloping vibrations. Several findings are made on the mechanisms of vibration generation and sustainability. First, the initial states (vibrating or fixed) of a cylinder may have a pronounced impact on the vibration of the other. Second, alternating reattachment, detachment, rolling up and shedding of the upper and lower gap shear layers all contribute to the vibrations. Third, the gap vortices around the base surface of the upstream cylinder produce positive work on the cylinder, sustaining the upstream cylinder vibration. Fourth, reattachment, detachment and switching of the gap shear layers result in largely positive work on the downstream cylinder, playing an important role in sustaining its vibration.

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Hattori, Yuji, und Ryu Komatsu. „Mechanism of aeroacoustic sound generation and reduction in a flow past oscillating and fixed cylinders“. Journal of Fluid Mechanics 832 (26.10.2017): 241–68. http://dx.doi.org/10.1017/jfm.2017.668.

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The aeroacoustic sound generated in a flow past two cylinders, one of which is oscillating and the other is fixed, is studied by direct numerical simulation. This problem involves key ingredients of the aeroacoustic noise generated from wind turbines, helicopters, axial flow fans and other turbomachinery: flow, a moving body and a fixed body. The corrected volume penalization method is successfully applied to resolve the sound pressure of aeroacoustic waves as a solution of the compressible Navier–Stokes equations. The sound pressure was shown to be in good agreement with the prediction by the Ffowcs Williams–Hawkings aeroacoustic analogy, which takes account of the cylinder motion, confirming the accuracy of the corrected volume penalization method. Prior to the case of two cylinders, sound generation in flow past a single oscillating cylinder is considered. The fluid motion can be either periodic or non-periodic depending on the frequency and the amplitude of cylinder oscillation. The acoustic power is significantly reduced when the fluid motion locks in to a frequency lower than the natural frequency of vortex shedding from a fixed cylinder. When a fixed cylinder is added, the acoustic power depends strongly on the distance between the cylinders, since that determines whether synchronization occurs and the phase difference between the three forces: the lift forces exerted on the two cylinders and the inertial force due to volume displacement effect of the oscillating cylinder. In particular, significant sound reduction is observed when the fixed cylinder is placed upstream and the frequency of the cylinder oscillation is set to the frequency for which the acoustic power is minimized in the single-cylinder case.

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Garg, Manish, Dharmpal Deepak und V. K. Gupta. „FE modeling of creep in linear and non-linear FGM cylinder under internal pressure“. Multidiscipline Modeling in Materials and Structures 10, Nr. 1 (03.06.2014): 94–105. http://dx.doi.org/10.1108/mmms-10-2012-0016.

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Purpose – The purpose of this paper is to investigate creep in an internally pressurized thick-walled, closed ends cylinder made of functionally graded composite, having linear and non-linear distribution of reinforcement, using finite element (FE) analysis. Design/methodology/approach – FE-based Abaqus software is used to investigate creep behavior of a functionally graded cylinder. The cylinder is made of composite containing linear and non-linearly varying distributions of reinforcement along the radius. The creep behavior has been described by Norton's power law. The creep stresses and strains have been estimated in linear and non-linear functionally graded materials (FGM) cylinders and compared with those estimated for a similar composite cylinder but having uniform distribution of reinforcement. Findings – The radial stress in the composite cylinder is observed to decreases over the entire radius upon imposing linear or non-linear reinforcement gradients. However, the tangential stress in the cylinder increases near the inner radius but decreases toward the outer radius, on imposing linear or non-linear reinforcement gradients. The creep strains in the FGM cylinders are significantly lower than those observed in a uniform composite cylinder. Originality/value – The creep strains in an internally pressurized functionally graded thick composite cylinder could be reduced significantly by employing non-linear distribution of reinforcement along the radial direction.

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Tang, Zhong, Haotian Zhang, Yuepeng Zhou und Yu Li. „Mutual Interference and Coupling Response of Multicylinder Vibration among Combine Harvester Co-Frame“. Shock and Vibration 2019 (16.06.2019): 1–14. http://dx.doi.org/10.1155/2019/1584391.

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Unbalanced vibrations of axial threshing cylinders on a combine harvester were coupled to each other through a frame. The intensified unbalanced vibration will shorten the working life of the axial threshing cylinder. In this paper, the theoretical modes of the axial threshing cylinder were carried out by using finite element analysis software ANSYS. The axis trajectory and speed fluctuation of the axial threshing cylinder under no-load state and threshing state were tested and analyzed. According to the amplitude and axis trajectory of the transmission shaft, as well as the variation law of the axial threshing cylinder speed, the influence of rice straw on the vibration under the threshing state was revealed. The rotation speeds of cylinder I and cylinder III were adjusted, and the amplitude of cylinder II transmission shaft was analyzed when cylinder II was under stable condition. Then the disturbance and coupling relationships among the unbalanced vibration of axial threshing cylinders were compared. Test results showed that the rotational frequency of the axial threshing cylinder was not in its resonance interval at rated speed. When the axial threshing cylinder was threshing, the horizontal amplitude increased by 0.366 mm. The vertical amplitude increased by 0.697 mm. The speed decreased from 763 rpm to about 750 rpm. The rotational frequency of the axial threshing cylinder would not cause the resonance. With the feeding of rice, the amplitude of the axial threshing cylinder increased slightly and the operating speed was lower than the rated speed. The unbalanced vibration of the axial threshing cylinder transmitted along the frame and coupled with each other, causing the vibration of the axial threshing cylinder to be intensified.

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Попиков, Viktor Popikov, Жданов, Yuriy Zhdanov, Канищев und Denis Kanishchev. „Improvement of technological equipment of the unit for removal of logging residues from the forest fringe in the thinnin“. Forestry Engineering Journal 5, Nr. 3 (15.11.2015): 210–19. http://dx.doi.org/10.12737/14169.

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The technique of optimization of the provisions of attachment points of hydraulic cylinders lifting mechanism, which takes into account, the fact that using standard cylinders with certain minimum and maximum length and stroke, when the distance from the axis of rotation of the boom to the upper hinge cylinder also changes the distance from the axis of rotation of the boom to the lower hinge cylinder. The tests described and tech-nology unit carried out in the areas of protective forest plantations, showed results that match the original requirements, which indicates the effectiveness of the work.

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LOCK, G. S. H., und W. J. O’CALLAGHAN. „FLOW THROUGH A ROW OF CLOSELY-SPACED CIRCULAR CYLINDERS NORMAL TO A COLD WATER STREAM“. Transactions of the Canadian Society for Mechanical Engineering 12, Nr. 3 (September 1988): 139–47. http://dx.doi.org/10.1139/tcsme-1988-0020.

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Flow near a row of parallel circular cylinders standing normal to a cross flow has been investigated experimentally. The cylinders spanned the height of the test section in a water tunnel in which the temperature was maintained close to the freezing point. Reynolds numbers, based on the mean bulk water velocity and the cylinder diameter, ranged between 3 x 103 and 3 x 104. The gap-diameter ratio g/D was set at five nominal values: 0.49, 0.20, 0.15, 0.10 and 0.06. For this range of conditions, static pressure readings were taken around the cylinder surfaces and at points well upstream and downstream of the cylinders. The overall static pressure change was converted into a pressure loss coefficient whose dependency on Reynolds number and gap-diameter ratio has been studied. The cylinder surface pressure profiles were used to determine flow behaviour in the gap region and in the wake. A critical transition at free stream Reynolds numbers much lower than that corresponding to a single cylinder was evident; a gap-diameter ratio near to 0.15 appeared to separate two different flow regimes. A cellular wake was often observed and found to be either metastable or bistable.

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Dissertationen zum Thema "Lower cylinder"

Dračka, Miroslav. „Návrh pracoviště pro dílčí montáž kompresoru klimatizace“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443204.

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The subject of this master´s thesis is the design of a single-purpose assembly device for pressing round seats into the cylinders of an air conditioning compressor. The whole thesis leads to a complete 3D model of the machine, including drawings. The 3D model and drawings were created in SOLIDWORKS.

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Buchteile zum Thema "Lower cylinder"

Salem Mohamed, Serageldin, Agnes M. Samuel, Herbert W. Doty, Salvador Valtierra und Fawzy H. Samuel. „Generation and Relaxation of Residual Stresses in Automotive Cylinder Blocks“. In Automotive System Engineering - New Methods and Optimal Solutions [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.93664.

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There is direct proportionality between ultimate tensile stress (UTS) and residual stresses (RS). Residual stresses gradually decrease with decreasing cooling/quenching rates. Quenching in cold water develops highest, whereas air cooling produces lowest, residual stresses. Significant increase in RS is observed in specimens with low dendrite arm spacing (high solidification rate), while lower residual stresses are measured in specimens with high dendrite arm spacing (low solidification rate). For I-4 and V-6 engine blocks, there is refinement in microstructure due to the increase in solidification rate along the cylinder length. The developed residual stresses are normally tensile in both engine types. Air cooling following solution heat treatment produces higher RS compared to warm water and cold water quenching. Solution heat treatment and freezing lead to maximum RS relaxation where 50% of the stresses are reduced after the solution heat treatment step. Aging time and temperature are directly proportional to the residual stresses relaxation. Relaxation of RS also depends on the geometry and size of the workpiece. It should be mentioned here that the I-4 and V-6 cylinder blocks were provided by Nemak-Canada (Windsor-Ontario-Canada). Residual stress measurements technique and procedure are typical of those used by the automotive industry in order to provide reliable data for industrial applications supported by intensive experiments.

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Pekguleryuz, Mihriban, Erol Ozbakir und Amir Rezaei Farkoosh. „Diesel Engine: Applications of Aluminum Alloys“. In Encyclopedia of Aluminum and Its Alloys. Boca Raton: CRC Press, 2019. http://dx.doi.org/10.1201/9781351045636-140000329.

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The Diesel engine, introduced by Rudolph Diesel in 1892, achieves a higher combustion ratio and fuel efficiency, has lower CO2 emissions per mile than the gasoline engine and is considered to be one of the most viable environmentally friendly technologies for vehicles. “Clean Diesel” using lower sulfur content fuel has become available since 2006. Currently, the Diesel engine and cylinder head are mostly cast iron to withstand the high compression pressures and temperatures of Diesel operation. Further weight reduction (40%–55%) via aluminum substitution in the Diesel engine would result in substantial fuel economy and increased environmental benefits. Current aluminum alloys cannot meet the requirements of the Diesel engine and a new research topic has emerged in aluminum materials technology to address these requirements. The main issue with aluminum alloys is the low resistance to thermal fatigue that results from the constrained expansion and contraction of the material in the interval regions leading to compressive creep deformation at 300°C during engine heat-up and to tensile deformation around 150°C during engine cooldown. This article discusses the performance requirements and the design principles for aluminum alloys for Diesel engine applications. Efforts on the modification of A356 and A319 alloys via Cu, Mg, Ni, Cr, V, Zr, Ti, and Mn addition are reviewed. Recent studies on Mn/Mo addition are presented and the related principles are introduced in designing high volume fraction, thermally stable, and uniform nanoscale dispersoids using solutes with opposite partitioning coefficients in aluminum.

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Magee, Patrick, und Mark Tooley. „Gas Supply and the Anaesthetic Machine“. In The Physics, Clinical Measurement and Equipment of Anaesthetic Practice for the FRCA. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199595150.003.0026.

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In Europe and other advanced medical communities, medical gases are generally supplied by pipeline, with cylinders available as back up. Large hospitals usually have oxygen supplied and stored in liquid form, since one volume of it provides 840 volumes of gaseous oxygen at 15◦C. It is stored in a secure Vacuum Insulated Evaporator (VIE) on the hospital site. The arrangement is shown in Figure 22.1. The VIE consists of an insulated container, the inner layer of which is made of stainless steel, the outer of which is made of carbon steel. The liquid oxygen is stored in the inner container at about−160◦C (lower than the critical temperature of−118◦C) at a pressure of between 700 and 1200 kPa. There is a vapour withdrawal line at the top of the VIE, from which oxygen vapour can go via a restrictor to a superheater, where the gas is heated towards ambient temperature. Where demand exceeds supply from this route, there is also a liquid withdrawal line from the bottom of the VIE, from which liquid oxygen can be withdrawn; the liquid can be made to join the vapour line downstream of the restrictor and pass either through the superheater or back to the top of the VIE. The liquid can also be made to pass through an evaporator before joining the vapour line. After passing through the superheater, the oxygen vapour is passed through a series of pressure regulators to drop the pressure down to the distribution pipeline pressure of 410 kPa. It should be remembered that no insulation is perfect and there is a pressure relief valve on top of the VIE in case lack of demand and gradual temperature rise results in a pressure build up in the container. There is a filling port and there is usually considerable wastage in filling the VIE; the delivery hose needs to be cooled to below the critical temperature, using the tanker liquid oxygen itself to cool the delivery pipe. The whole VIE device is mounted on a hinged weighing scale and is situated outside the hospital building, protected by a caged enclosure, which also houses two banks of reserve cylinders.

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Konferenzberichte zum Thema "Lower cylinder"

Aouichi, Abdelhamid, und Jacques Graizon. „Modeling of the Dynamic Behavior of the Lower Portion of the Cylinder Block“. In SAE International Congress and Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1986. http://dx.doi.org/10.4271/860233.

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Li, Ningyu, Hongrae Park, Hai Sun und Michael M. Bernitsas. „Numerical Simulation and Experiments of Flow-Induced Oscillations of Single-Cylinder With Large Passive Turbulence Control“. In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-19142.

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Abstract Passive turbulence control (PTC) is being used in the Marine Renewable Energy Laboratory (MRELab) of the University of Michigan to enhance flow induced oscillations (FIO) of cylinders in the VIVACE (Vortex Induced Vibration for Aquatic Clean Energy) Converter. Large PTC triggers VIV and galloping at lower flow speeds for energy harvesting. Currently, FIO of cylinders with large PTC for high Re has received limited attention and, particularly, the effect of variable PTC height on FIO of cylinders. The vast majority of ocean currents, rivers, and tides are too slow for Marine Hydro Kinetic (MHK) energy technologies to harness it. In order to enhance FIO and to initiate galloping earlier, a circular cylinder is geometrically modified using straight strips placed on the cylinder surface symmetrically PTC strips on the cylinder effectively change the flow properties. In the present study, the FIO of a single-cylinder with large PTC, on end linear-springs, is modelled and simulated using a Fluid-Structure Interaction (FSI) code. Results are verified by corresponding experimental data. Results show that VIV onset occurs at lower Re for large-PTC cylinder in comparison with lower-PTC cylinder. Contrary to smooth cylinders for which the amplitude ratio is small in the transition region between VIV and galloping, application of large PTC leads to high amplitude response in the transition region. The mechanism behind this observation is the further departure of the geometry from the smooth circular cylinder. The latter does not exhibit galloping due to flow and geometric symmetry in all directions. Moreover, in the galloping region, the amplitude ratio increases with the height of PTC. Earlier onset of galloping and enhancement of geometric asymmetry support this observation as well.

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Ernst, Peter, und Bernd Distler. „Optimizing the Cylinder Running Surface / Piston System of Internal Combustion Engines Towards Lower Emissions“. In 2012 Small Engine Technology Conference & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2012. http://dx.doi.org/10.4271/2012-32-0092.

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Horimoto, Yasufumi, Yusuke Suzuki, Kazuki Hagiwara und Yasuo Kawaguchi. „Experimental Analysis of Turbulent Wake Development Behind a Permeable Cylinder“. In ASME-JSME-KSME 2019 8th Joint Fluids Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/ajkfluids2019-4790.

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Abstract To investigate the effect of permeability on turbulent wake behind a cylinder in uniform flow, we conduct particle image velocimetry on turbulent wake behind permeable cylinders, which are made of mesh sheets, of different permeabilities and compare the results with those for a solid cylinder. For relatively lower permeability, turbulent wake is quite similar to the case for a solid cylinder except for a slight shift in the streamwise direction of the reversed flow region implying turbulent Kármán vortex shedding. On the other hand, for higher permeability, the structure of turbulence is qualitatively different. More concretely, turbulent Kármán vortices disappear. Interestingly, however, the momentum deficit for such flow is comparable with that of a solid cylinder. This considerable momentum deficit can be understood with isotropic turbulence caused by the flow penetrating through the mesh constructing the cylinders. These results imply that turbulent wake behind a permeable cylinder involves dynamics both of wake and grid turbulence and the latter one dominates when permeability is sufficiently high.

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Smith, Barton L., Jack J. Stepan und Donald M. McEligot. „Velocity and Pressure Measurements Along a Row of Confined Cylinders“. In ASME 2006 2nd Joint U.S.-European Fluids Engineering Summer Meeting Collocated With the 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/fedsm2006-98186.

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The results of flow experiments performed in a cylinder array designed to mimic a VHTR Nuclear Plant lower plenum design are presented. Pressure drop and velocity field measurements were made. Based on these measurements, five regimes of behavior are identified that are found to depend on Reynolds number. It is found that the recirculation region behind the cylinders is shorter than that of half cylinders placed on the wall representing the symmetry plane. Unlike a single cylinder, the separation point is found to always be on the rear of the cylinders, even at very low Reynolds number. Boundary layer transition is found to occur at much lower Reynolds numbers than previously reported.

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Gorman, Ian M. O., Darina B. Murray, Gerard Byrne und Tim Persoons. „Natural Convection From Isothermal Horizontal Cylinders“. In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-11213.

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The research described here is concerned with natural convection from isothermal cylinders, with a particular focus on the interaction between a pair of vertically aligned cylinders. Prime attention was focused on how the local heat transfer characteristics of the upper cylinder are affected due to buoyancy induced fluid flow from the lower cylinder. Tests were performed using internally heated copper cylinders with an outside diameter 30mm and a vertical separation distance between the cylinders ranging from two to three cylinder diameters. Plume interaction between the heated cylinders was investigated within a Rayleigh number range of 2×106 to 6×106. Spectral analysis of the associated heat transfer interaction is presented showing that interaction between the cylinders causes oscillation of the thermal plume. The effect of this oscillation is considered as a possible enhancement mechanism of the heat transfer performance of the upper cylinder.

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Chhabra, Manish. „Vibro-Acoustic Optimization of 4 Cylinder Diesel Engine Oil Pan Structure for Lower Sound Radiation.“ In 9th International Styrian Noise, Vibration & Harshness Congress: The European Automotive Noise Conference. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2016. http://dx.doi.org/10.4271/2016-01-1771.

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Akosile, O. O., und D. Sumner. „An Experimental Investigation of Staggered Circular Cylinders in a Uniform Planar Shear Flow“. In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32180.

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Two circular cylinders of equal diameter, arranged in staggered configurations of P/D = 1.125 and 1.25, were immersed in a uniform planar shear flow, at Re = 5.0×104 and a dimensionless shear parameter of K = 0.05. The mean aerodynamic forces and the vortex shedding frequencies were measured for the upstream and downstream cylinders at each P/D. Under uniform, no-shear flow conditions, K = 0, the flow field of the cylinder group is similar to a single bluff body. As the incidence angle is varied from α = 0° to 90°, the forces on each cylinder undergo discontinuous changes, or attain local minimum or maximum values, at several critical incidence angles. At small α, the Strouhal number is greater than that of a single, isolated circular cylinder, whereas at high α the Strouhal number is lower than the single-cylinder value. The effects of shear, K = 0.05, on the aerodynamic forces were different depending on whether the downstream cylinder was situated at a higher or lower centreline velocity compared to the upstream cylinder. The planar shear flow had its greatest influence when the cylinders were in a nearly side-by-side arrangement. This indicated that the effect of shear was mostly on the flow through the gap between the cylinders. The lift coefficient data were mostly unchanged by the shear flow, the drag coefficient data were lowered, and there were shifts in the critical incidence angles. The influence of shear on vortex shedding was less pronounced, but there was a small reduction in Strouhal number compared to the no-shear case.

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Allen, Don W., Dean L. Henning und Li Lee. „Vortex-Induced Vibration Current Tank Tests of Two Equal Diameter Cylinders Offset From Tandem“. In ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/omae2004-51116.

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Two equal diameter ABS cylinders, offset from tandem, were subjected to uniform and sheared flows in a current tank at subcritical Reynolds numbers. Both tubes were filled with a saltwater solution to produce a specific gravity of 1.38. An accelerometer in each cylinder was used to measure the vortex-induced vibration response, which primarily varied between the third and seventh transverse bending modes. The cylinders were spaced at 3 to 20 diameters in the in-line direction and at 0, 0.5, and 1.0 diameter in the offset direction. Test results indicate that a downstream cylinder, for a pure tandem (no offset) configuration, experiences less vibration than the upstream cylinder when the upstream cylinder rms displacement is larger than about 0.35D. Offsets of 0.5 and 1.0 times the outside diameter produce lower vibration of the downstream cylinder relative to that of the upstream cylinder.

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Momoki, Satoru, Kaoru Toyoda, Takashi Yamada, Toru Shigechi und Tomohiko Yamaguchi. „Experiments and Analysis on Film Boiling Heat Transfer Around a Finite-Length Vertical Cylinder With a Convex Surface Swelling Downward“. In 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48307.

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A method of predicting the overall heat transfer coefficient and the temperature at the lower limit of film boiling for a finite-length cylinder with flat top and bottom surfaces has been researched and proposed in a previous paper. This paper presents and compares an analysis in the case of a cylinder with a hemispherical bottom. The film boiling heat transfer around a vertical silver cylinder with a convex hemispherical bottom surface is investigated both experimentally and analytically in the present study. The obtained results are also compared and discussed with the authors’ previous results for a finite-length cylinder with flat top and bottom surfaces. Quenching experiments were performed using silver cylinders in saturated water. The diameter and length of the test cylinders are 32mm and 48mm, respectively. The test cylinder was heated up to about 600°C in an electric furnace and then cooled down in saturated quiescent water at atmospheric pressure. The resultant cooling and boiling curves and photographs of the film boiling phenomena are presented and discussed. The average heat transfer performance of the hemispherically bottomed cylinder is about 20% higher than that of the flat bottomed cylinder. The degree of wall superheating at the lower limit of film boiling is about 133K. The saturated film boiling heat transfer around the vertical finite-length cylinder with a convex hemispherical bottom was analyzed by taking into account the convective heat transfers from the bottom, side and top surfaces of the cylinder. The resulting analytical data correlated closely with the experimental data in the present study.

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