Academic literature on the topic 'Experimental roughness'

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Journal articles on the topic "Experimental roughness"

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Cotta, M. A., R. A. Hamm, S. N. G. Chu, R. Hull, L. R. Harriott, and H. Temkin. "Kinetic roughness in epitaxy (experimental)." Materials Science and Engineering: B 30, no. 2-3 (March 1995): 137–42. http://dx.doi.org/10.1016/0921-5107(94)09008-4.

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HERWIG, H., D. GLOSS, and T. WENTERODT. "A new approach to understanding and modelling the influence of wall roughness on friction factors for pipe and channel flows." Journal of Fluid Mechanics 613 (October 1, 2008): 35–53. http://dx.doi.org/10.1017/s0022112008003534.

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In this study, it is shown how the equivalent sand roughness required in the Moody chart can be calculated for arbitrarily shaped wall roughnesses. After a discussion of how to define the wall location and roughness height in the most reasonable way, a numerical approach based on the determination of entropy production in rough pipes and channels is presented. As test cases, three different two-dimensional roughness types have been chosen which are representative of regular roughnesses on machined surfaces. In the turbulent range, skin friction results with these test roughnesses can be linked to Nikuradse's sand roughness results by a constant factor. For laminar flows, a significant effect of wall roughness is identified which in most other studies is neglected completely. The dissipation model of this study is validated with experimental data for laminar and turbulent flows.
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LIU, CHAOFENG, YUSHAN NI, and YONG RAO. "ROUGHNESS EFFECT OF DIFFERENT GEOMETRIES ON MICRO GAS FLOWS BY LATTICE BOLTZMANN SIMULATION." International Journal of Modern Physics C 20, no. 06 (June 2009): 953–66. http://dx.doi.org/10.1142/s0129183109014114.

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The roughness effects of the gas flows of nitrogen and helium in microchannels with various relative roughnesses and different geometries are studied and analyzed by a lattice Boltzmann model. The shape of surface roughness is simulated to be square, sinusoidal, triangular, and fractal. Numerical computations compared with theoretical and experimental studies show that the roughness geometry is an important factor besides the relative roughness in the study of the effects of surface roughness. The fractal boundary presents a higher influence on the velocity field and the resistance coefficient than other regular boundaries at the same Knudsen number and relative roughness. In addition, the effects of rarefaction, compressibility, and roughness are strongly coupled, and the roughness effect should not be ignored in studying rarefaction and compressibility of the microchannel as the relative roughness increases.
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ZHANG, XINPING, SIRONG YU, ZHENMING HE, and YAOXIN MIAO. "WETTING OF ROUGH SURFACES." Surface Review and Letters 11, no. 01 (February 2004): 7–13. http://dx.doi.org/10.1142/s0218625x04005925.

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This paper focuses on effects of roughness on wettability. According to Wenzel's equation, the transition of theoretical wetting contact angles is 90°, whereas many experimental results have indicated that such a transition takes place at contact angles smaller than 90°. A new model of wetting on roughness surface is established in this paper. The model indicates that the influencing factors of wetting on roughness surface include not only equilibrium contact angle θ0 and surface roughness, but also the system of liquids and solid substrates. There is a corresponding transition angle for every surface roughness, and the transition angle is lower than 90°. Surface roughness is propitious to improve the contact angle only when θ0 is lower than the transition angle. The effect of surface roughness on the contact angle increases with the increase of rE. To engineer the surface with different roughnesses, a Ti test sample is polished with sandpaper with abrasive number 350, 500, 1000 and 2000; the contact angles of water on Ti are measured by the sessile drop method. The results of the theoretical analysis agree with experimental ones.
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Mitsuya, Y., T. Ohkubo, and H. Ota. "Averaged Reynolds Equation Extended to Gas Lubrication Possessing Surface Roughness in the Slip Flow Regime: Approximate Method and Confirmation Experiments." Journal of Tribology 111, no. 3 (July 1, 1989): 495–503. http://dx.doi.org/10.1115/1.3261957.

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The average film thickness theory is extended to gas lubrication possessing surface roughness in the slip flow regime. A simplified averaged Reynolds equation is derived and its applicability is confirmed through comparing with experiments. This averaging equation makes use of the mixed average film thickness defined as Havem = αHm + (1 − α)Hmˆ, where m = 1, 2 and 3; α indicates the mixing ratio; and H¯ and Hˆ denote the arithmetically and harmonically averaged film thicknesses. The experiments were performed using computer flying heads having precisely photolithography-fabricated longitudinal, transverse or checkered pattern roughnesses under submicron spacing conditions. From the excellent agreement obtained between the calculated and experimental results, it can be concluded that the assumption that velocity slippage occurs along the surface even if roughnes is present is justified, and that the approximate method is applicable for determining the surface roughness effects in the slip flow regime.
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Mosleh, Mohsen, Keron Bradshaw, Sonya Smith, John Belk, and Khosro Shirvani. "Roughness Effect in Micropitting and Rolling Contact Fatigue of Silicon Nitride." Ceramics 2, no. 1 (February 18, 2019): 135–47. http://dx.doi.org/10.3390/ceramics2010013.

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An experimental analysis of the role of surface roughness parameters on micropitting and the succeeding rolling contact fatigue (RCF) of silicon nitride against AISI 52100 steel under lubricated conditions was performed. In accelerated fatigue tests using a four-ball tester, the arithmetic mean, root mean square, and peak-to-valley roughnesses of silicon nitride surfaces varied, while the roughness of the steel surface was unchanged. The correlation between the fatigue life and roughness parameters for silicon nitride was obtained. The peak-to-valley roughness was the roughness parameter that dominantly affected the RCF life of silicon nitride. The micropitting of surfaces leading to fatigue intensified as the roughness was increased. Extensive micropitting was observed on the rolling track beyond the trailing edge of the spall region in the circumferential direction.
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Vaceanu, Bogdan Constantin, Gheorghe Nagit, and Vasile Huian. "Experimental Researches upon Changes of a Pipe's Roughness after Hydroformation." Applied Mechanics and Materials 371 (August 2013): 111–15. http://dx.doi.org/10.4028/www.scientific.net/amm.371.111.

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Surface roughness was studied in the tube hydroforming process, considering the quality of the material and the coefficient of friction between the work piece and die. Other researchers have studied the surface roughness to the front of an aluminum pipe [. The aim of this work was to analyze changes in a copper pipe roughness occurred after hydroforming process with fluid. Effects of changing roughness were studied, following the deformation of the material in the work area and roughness changes occurring in the material flow. After achieving hydroforming process, the surface roughness was measured by electron microscopy SEM in different areas of the hydro formed tube. After hydroforming process, an increase of surface roughness in connection areas of the mold to the curvature and the transverse direction of the pipe.
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Teixidor, Daniel, Guillem Quintana, and Joaquim de Ciurana. "Experimental Introduction to Surface Roughness Parameters Measurement." Materials Science Forum 759 (July 2013): 63–71. http://dx.doi.org/10.4028/www.scientific.net/msf.759.63.

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Surface roughness influences the performance of a finished part. In machining operations, the surface roughness generated is influenced by an enormous set of factors. In ball end milling operations, the geometric characteristics of the cut clearly affect the surface crests generated. This paper presents an experimental methodology that permits engineering students to identify and analyze the surface roughness. The methodology is applicable to training courses and surface texture generation as well.
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Nguyen, Duc Nam, Ngoc Le Chau, Thanh-Phong Dao, Chander Prakash, and Sunpreet Singh. "Experimental study on polishing process of cylindrical roller bearings." Measurement and Control 52, no. 9-10 (August 20, 2019): 1272–81. http://dx.doi.org/10.1177/0020294019864395.

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The surface quality and accuracy of the geometry of the cylindrical rollers are important factors for bearing life. This paper presents effects of machining parameters on the surface roughness, topography and roundness of cylindrical rollers through the lapping and polishing experiments. And then the surface roughness of the cylindrical rollers is optimized. The results found that the surface roughness of rollers is significantly changed in lapping process with different abrasive particle sizes, while the surface roughness has slightly reduced in polishing process. It also indicated that the smoother surfaces with better roughness can be obtained after lapping and polishing process. In addition, the surface roughness of cylindrical rollers is rapidly reduced from Ra of 0.5 µm to Ra of 0.063 µm after the 3-h lapping process and Ra of 0.013 µm after the 1-h polishing process. The surface topography of rollers can be achieved by the smoother surface when loads are from 25 to 35 N in lapping process, and the loads are from 35 to 40 N in polishing process. Finally, the Taguchi method is applied to optimize the surface roughness in polishing process. The result found that the optimal surface roughness achieves 0.015 µm with respect to the time of 35 min and type of 4000# Al2O3.
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Pöller, Franziska, Félix Salazar Bloise, Martin Jakobi, Shengjia Wang, Jie Dong, and Alexander W. Koch. "Non-Contact Roughness Measurement in Sub-Micron Range by Considering Depolarization Effects." Sensors 19, no. 10 (May 14, 2019): 2215. http://dx.doi.org/10.3390/s19102215.

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The characteristics of a surface, particularly the roughness, play an important role in different fields of the industry and have to be considered to ensure quality standards. Currently, there are numerous sophisticated methods for measuring surface roughness but plenty of them cause long-term damage because they are in contact with the sample. This article presents a non-contact method to accurately determine small surface roughnesses resulting from the consideration of the depolarization effects caused by the rough surface. This technique can be applied as an extension in various roughness measurements and improves the approach of Chandley’s technique, which does not take into account the depolarization of the light scattered by the sample. The experimental setup and the measurements are easy to perform. The essential component is a quarter wave plate, which is incorporated into a Michelson interferometer. With the resulting two different contrasts and the recorded intensities of the sample and the reference mirror, the surface roughness can be estimated straightforwardly. This article details the theoretical approach, followed by the experimental results and the corresponding uncertainties. The experimental results are compared with Chandley’s method. In order to have reference roughness values of the samples, measurements with a stylus profilometer and with a confocal microscope are performed and compared.
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Dissertations / Theses on the topic "Experimental roughness"

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Kalogeropoulos, Elias. "Experimental investigation of roughness effects on centrifugal compressor performance." Thesis, University of Sussex, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326927.

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Petry-Johnson, Travis T. "Experimental investigation of spur gear efficiency." Connect to resource, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1209585550.

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Hu, Jin. "Experimental and theoretical investigation of roughness effects on thin laminar fluid films." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27957.pdf.

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Brackbill, Tim. "Experimental investigation on the effects of surface roughness on microscale liquid flow /." Online version of thesis, 2008. http://hdl.handle.net/1850/6136.

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Fouflias, Dimitrios. "An experimental and computational analysis of compressor cascades with varying surface roughness." Thesis, Cranfield University, 2009. http://dspace.lib.cranfield.ac.uk/handle/1826/7029.

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This thesis presents a CFD and experimental analysis associated with the parameter compressor fouling and a CFD analysis associated with the parameter on-line compressor washing of industrial gas turbines. On-line compressor washing is very popular and quite effective in the industrial gas turbine operational scheme. Many companies apply on-line washing with the engine running at normal speed so as to avoid downtime periods for off-line cleanings that could cause significant economic drawbacks. At this thesis vital parameters affecting compressor cleaning of an industrial gas turbine were examined and combined in such a way so as to provide adequate coverage of the frontal inlet guide vane area which is critical for effective cleaning. The parameters investigated were water injection nozzle position, inclination with respect to the engine centerline, injection velocity and nozzle spray angles. However, before applying compressor washing, compressor fouling comes into consideration. For this purpose a compressor cascade tunnel (test rig) was designed and come into operation in order to examine different levels of fouling. The cascade test rig involved as well a washing kit for future cleaning of the cascade blades. This work related to the cascade design released a lot of information about designing suction type compressor cascade test rigs by analysing the flow inside the cascade rig computationally and three-dimensionally via CFD tools. The results in terms of the quality of flow obtained for the current test rig were also compared with modified versions of the test rig, one which involved a bigger plenum area behind the cascade test section and one involving the current rig running in a blowing type mode. The CFD results coming out from the compressor cascade tunnel for the different fouling levels, were analysed in terms of mass flow capacity and polytropic efficiency reduction due to fouling by using Howell’s theory (1945) and they were used as inputs for running performance simulation in terms of an industrial gas turbine engine using the performance simulation code Turbomatch. Therefore, a correlation between cascade fouling and real engine uniformly stage spread fouling was achieved. At high levels fouling where the 254 microns roughness height takes place, the nondimensional air mass flow reduction can reach levels of 1.6% and the drop in compressor efficiency can touch the value of 5%. The CFD results obtained after running all the simulation scheme for the different roughness levels, were compared to the actual experimental results coming from running the compressor cascade rig with the same fouling scheme of roughness. Applying Howell’s theory (1945), the fouled cascade was correlated to a uniformly fouled stage and a real industrial gas turbine. This time input in the Turbomatch code was the percentage deterioration in compressor efficiency calculated from correlated cascade data. This deterioration reaches a high level of 11 % when the fouling particle size is 254 microns.
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Olsson, Niklas, and Christian Selberg. "Numerical simulation and experimental validation of a manufactured wing profile." Thesis, Högskolan Väst, Avdelningen för Industriell ekonomi, Elektro- och Maskinteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-14287.

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The background for this thesis originates from a study of the flow characteristics for an airfoil of the type NACA0018. The aim for this thesis was to evaluate how the characteristics of the flow over the NACA0018 profile depend on surface roughness. Airfoils were manufactured in Aluminum by Computer Numerical Control-milling and in polylactide polymer using a 3D-printer, where some of the profile surfaces were postprocessed with sandpaper in various grain sizes. The surface roughness of the profiles was evaluated in a 3D optical profilometer using white light interferometry from Filmetrics. By that technique 3D surface plots were created. The manufactured airfoils were tested in a wind tunnel where the achieved data was made dimensionless for comparative purposes. The computational fluid dynamics simulations were performed in Ansys Fluent and compared against the wind tunnel data as well as with the data from a previously made study at htw saar. The results from the wind tunnel tests show that the surface roughness has an effect on the flow characteristic of the airfoil, where different angles of stall were observed in the comparison. The difference for the dimensionless numbers coefficient of lift and drag show that the manufactured aluminum airfoil performs better compared to the 3D-Printed airfoil in this study. It has a higher performance mean value for both of these coefficients in a span of angles between 0 and 30 degrees. When compared, the results from the simulations and wind tunnel experiments do match in some cases, where the dimensionless coefficients and stall angle coheres. Further studies based on this report are recommended, where small geometric changes to the profile could be tested and validated.
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Wen, Quan. "An experimental investigation of inner surface roughness on friction factor for horizontal micro-tubes." Thesis, University of Macau, 2010. http://umaclib3.umac.mo/record=b2493677.

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Lundberg, Staffan. "Experimental investigations in wood machining related to cutting forces, sawdust gluing, and surface roughness." Licentiate thesis, Luleå tekniska universitet, Matematiska vetenskaper, 1994. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17499.

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Plogmann, Benjamin [Verfasser]. "Experimental investigations on roughness initiated instability and transition in airfoil boundary layers / Benjamin Plogmann." München : Verlag Dr. Hut, 2015. http://d-nb.info/1079768254/34.

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Tee, Boon Tuan. "An experimental study of the response of turbulent boundary layers to changes in roughness." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610435.

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Books on the topic "Experimental roughness"

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J, Orr D., and United States. National Aeronautics and Space Administration., eds. Spectral analysis and experimental modeling of ice accretion roughness. Washington, D.C: American Institute of Aeronautics and Astronautics, 1996.

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United States. National Aeronautics and Space Administration., ed. Theoretical and experimental models of the diffuse radar backscatter from Mars. Ann Arbor, Mich: University of Michigan, Radiation Laboratory, Dept. of Electrical Engineering and Computer Science, 1995.

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United States. National Aeronautics and Space Administration., ed. Theoretical and experimental models of the diffuse radar backscatter from Mars. Ann Arbor, Mich: University of Michigan, Radiation Laboratory, Dept. of Electrical Engineering and Computer Science, 1995.

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Mölder, Meelis. Parameterization of the interaction between the atmosphere and the land surface by means of roughness lengths: An experimental study over various surfaces. Uppsala: Sveriges lantbruksuniversitet, Institutionen för ekologi och miljövård, 1993.

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Spectral analysis and experimental modeling of ice accretion roughness. Washington, D.C: American Institute of Aeronautics and Astronautics, 1996.

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National Aeronautics and Space Administration (NASA) Staff. Experimental and Numerical Study of Roughness-Induced Instabilities in a Mach 3. 5 Boundary Layer. Independently Published, 2019.

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Book chapters on the topic "Experimental roughness"

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Yates, John T. "Ion Beam Polishing of Crystals to Subnanometer Roughness." In Experimental Innovations in Surface Science, 238–39. New York, NY: Springer New York, 1998. http://dx.doi.org/10.1007/978-1-4612-2304-7_73.

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Livya, E., R. Sai Anirudh, V. Vignesh, B. Prasannavenkatesh, and S. Nadaraja Pillai. "Experimental Analysis of Implementing Roughness on NACA 0018 Airfoil." In Lecture Notes in Mechanical Engineering, 91–96. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-2697-4_10.

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Hötte, Felix, Oliver Günther, Christoph von Sethe, Matthias Haupt, Peter Scholz, and Michael Rohdenburg. "Lifetime Experiments of Regeneratively Cooled Rocket Combustion Chambers and PIV Measurements in a High Aspect Ratio Cooling Duct." In Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 279–93. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53847-7_18.

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Abstract This paper aims at experimental investigations of the life limiting mechanisms of regeneratively cooled rocket combustion chambers, especially the so called doghouse effect. In this paper the set up of a cyclic thermo-mechanical fatigue experiment and its results are shown. This experiment has an actively cooled fatigue specimen that is mounted downstream of a subscale GOX-GCH$$_{\text {4}}$$ combustion chamber with rectangular cross section. The specimen is loaded cyclically and inspected after each cycle. The effects of roughness, the use of thermal barrier coatings, the length of the hot gas phase, the oxygen/fuel ratio and the hot gas pressure are shown. In a second experiment the flow in a generic high aspect ratio cooling duct is measured with the Particle Image Velocimetry (PIV) to characterize the basic flow. The main focus of the analysis is on the different recording and processing parameters of the PIV method. Based on this analysis a laser pulse interval and the window size for auto correlation is chosen. Also the repeatability of the measurements is demonstrated. These results are the starting point for future measurements on the roughness effect on heat transfer and pressure loss in a high aspect ratio cooling duct.
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Priyankara, K. P. M., and G. I. P. Perera. "Experimental Investigation to Achieve Minimum Surface Roughness in Wire EDM Process." In Lecture Notes in Civil Engineering, 239–51. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-9749-3_22.

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Li, Songhua, Kechong Wang, and Jian Sun. "Experimental Study on Grinding Surface Roughness of Full-Ceramic Bearing Ring." In Advances in Intelligent Systems and Computing, 181–90. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4575-1_18.

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Tay, C. J., S. H. Wang, and C. Quan. "Surface Roughness Measurement of a Semi-Conductor Wafer Using Laser Scattering Technique." In Experimental Analysis of Nano and Engineering Materials and Structures, 327–28. Dordrecht: Springer Netherlands, 2007. http://dx.doi.org/10.1007/978-1-4020-6239-1_162.

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Philip Selvaraj, D. "Experimental Analysis of Surface Roughness of Duplex Stainless Steel in Milling Operation." In Lecture Notes in Mechanical Engineering, 373–82. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1724-8_36.

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Puckert, Dominik K., Tristan M. Römer, Giacomo Scibelli, and Ulrich Rist. "Experimental Investigation on Roughness-Induced Transition Under the Influence of Freestream Turbulence." In Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 205–14. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-79561-0_20.

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Janke, Erik. "Receptivity of Three-Dimensional Boundary Layers to Roughness and Suction — Linear and Nonlinear Effects." In New Results in Numerical and Experimental Fluid Mechanics III, 367–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-540-45466-3_43.

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Ngo, Loc P., Tai P. Nguyen, and Thanh T. Tran. "Experimental Investigation of Effect of Process Parameters on Surface Roughness in Electrochemical Machining." In Springer Proceedings in Materials, 255–70. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-45120-2_22.

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Conference papers on the topic "Experimental roughness"

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Amra, C., and L. Bruel. "Theoretical and experimental comparison of different techniques to characterize surface roughness." In Surface Roughness and Scattering. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/surs.1992.stua5.

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Characterization of surface roughness remains today a crucial problem, in particular in the fields of optics and mechanics. Many techniques [1] have been developed in this aim, and involve scatterometers or profilometers. However the measured roughness values may strongly vary from one technique to another, and it becomes necessary to normalize the statistical parameters that describe surface defects. In this paper we present experimental results obtained from 3 techniques that are Angle-Resolved light Scattering measurements (ARS), mechanical profilometer (Talystep) and Atomic Force Microscope (AFM). Moreover, a theoretical tool is provided for a detailed investigation of the apparatus functions relative to the light scattering and Talystep techniques.
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Dainty, J. C. "Experimental Measurements of Enhanced Backscattering and Related Effects from Randomly Rough Surfaces." In Surface Roughness and Scattering. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/surs.1992.stua2.

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Light scattering from randomly rough surfaces of relatively low root-mean-square (rms) slope and long correlation length (> λ) is well-understood, at least for moderate angles of incidence, in terms of physical optics (Kirchhoff) theory. However, until the past five years, there has been little experimental or theoretical work carried out on surfaces with a large rms slope for which multiple scattering occurs. One consequence of strong multiple scattering is the presence of an enhanced backscatter peak: this peak has a similar origin to that observed from strongly multiple scattering volume media, such as white paint, and analogous effects are observed in the propagation of light through turbulence in "double pass" geometries.
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Coleman, Stephen, Juan Fedele, and Marcelo Garcia. "Development of Closed-Conduit Roughness." In Hydraulic Measurements and Experimental Methods Specialty Conference (HMEM) 2002. Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40655(2002)22.

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Smart, G. M., and J. M. Walsh. "Direct Measurement of Alluvial Channel Roughness." In Hydraulic Measurements and Experimental Methods Specialty Conference (HMEM) 2002. Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40655(2002)81.

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Liu, Yu, Ann Dowling, Ho-Chul Shin, and Alexander Quayle. "Experimental Study of Surface Roughness Noise." In 13th AIAA/CEAS Aeroacoustics Conference (28th AIAA Aeroacoustics Conference). Reston, Virigina: American Institute of Aeronautics and Astronautics, 2007. http://dx.doi.org/10.2514/6.2007-3449.

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Méndez, E. R., R. Espinosa, J. F. Aguilar, H. M. Escamilla, and Z. H. Gu. "Light Scattering from Photofabricated Surfaces with non-Gaussian Statistical Properties." In Surface Roughness and Scattering. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/surs.1992.stua3.

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The scattering of light from randomly rough surfaces has attracted a great deal of attention in recent years. Despite all this work, several aspects of the problem remain poorly understood. More specifically, analytical progress is difficult in situations when multiple scattering effects are important, when the statistics of the surface are non-Gaussian, and when the surface profile is multiscale (fractal-like). For a number of years, it has been clear that more systematic studies of the problem are required. In particular, for experimental work, it is important to be able to fabricate surfaces with known statistical properties in a more or less controlled way.
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Song, Majinyang, Constance Kang Ting Teoh, and Ruojun Ding. "Thickness and roughness measurement using a reflective digital holographic microscope." In Fourth International Conference on Experimental Mechanics, edited by Chenggen Quan, Kemao Qian, Anand K. Asundi, and Fook S. Chau. SPIE, 2009. http://dx.doi.org/10.1117/12.851469.

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Saillard, M. "Scattering of Electromagnetic Surface Waves by Rough Surfaces." In Surface Roughness and Scattering. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/surs.1992.sma6.

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The localization of classical waves, like electromagnetic or acoustic ones, has been widely studied for a few years [1]. For one- or two-dimensional systems, the localization of propagating modes is theoretically predicted at any non vanishing disorder. For instance, surface plasmon polaritons (SPP), which are extended modes of flat metallic surfaces, become localized in the presence of random roughness [2,3]. Localization of SPP on rough surfaces has important contributions to surface-enhanced phenomena [2] and gives birth to the phenomenon of enhanced backscattering for shallow surfaces [3]. But it seems that no experimental confirmation exists yet [1]. To my knowledge, no direct numerical evidence of localization has neither been published, since only backscattering peaks, considered as a signature of localization, are exhibited. Thanks to the model achieved in our laboratory [4], it is now possible.
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Ronnow, D., M. Bergkvist, A. Roos, and C.-G. Ribbing. "Determination of Interface Roughness Using A Wavelength Scanning TIS Instrument." In Surface Roughness and Scattering. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/surs.1992.stub7.

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Optical scattering from surface micro irregularities at a specific wavelength is directly related to the RMS-roughness value of the surface1. It is usually measured by a TIS (Total Integrated Scatter) instrument. In its’ conventional application this method can only be used to investigate the front surface of opaque samples. In the case of transparent samples or samples coated with a transparent film, one must handle two scattering interfaces as well as possible interference effects in the film. The resulting light scattering cannot be described by the standard TIS equation. By combining the scalar scattering theory with the Fresnel formalism we have obtained a model which predicts the scattering from a double layer as a function of wavelength. By fitting model calculations to experimental scattering spectra with the interface roughness values as parameters we can extract the rms-roughness values of the two interfaces. The model has been described elsewhere2. Using the scattering spectra and such fitting calculations we can conveniently, and non-destructively, determine the RMS-roughness of a "hidden" interface.
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Wan, Yanling, Jun Lou, Jinkai Xu, Xuerui Zhang, and Huadong Yu. "Experimental study of surface roughness effects on wettability." In 2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO). IEEE, 2013. http://dx.doi.org/10.1109/3m-nano.2013.6737392.

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Reports on the topic "Experimental roughness"

1

Bowersox, Rodney D. W. Experimental Investigation of High-Speed Boundary Layers with Wall Roughness. Fort Belvoir, VA: Defense Technical Information Center, February 2001. http://dx.doi.org/10.21236/ada387235.

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2

GATHIMBA, Naftary, and Yasuo KITANE. INFLUENCE OF SURFACE ROUGHNESS ON DUCTILITY OF CORRODED STEEL: AN EXPERIMENTAL STUDY. The Hong Kong Institute of Steel Construction, December 2018. http://dx.doi.org/10.18057/icass2018.p.138.

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3

Coleman, Hugh W., Robert P. Taylor, M. H. Hosni, Glenn B. Brown, and Philip H. Love. An Experimental Study of Surface Roughness Effects on Turbulent Boundary Layer Flow and Heat Transfer. Fort Belvoir, VA: Defense Technical Information Center, April 1989. http://dx.doi.org/10.21236/ada212099.

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4

Andrawes, Bassem, Ernesto Perez Claros, and Zige Zhang. Bond Characteristics and Experimental Behavior of Textured Epoxy-coated Rebars Used in Concrete Bridge Decks. Illinois Center for Transportation, January 2022. http://dx.doi.org/10.36501/0197-9191/22-001.

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The deterioration of bridge decks is a problem typically associated with the corrosion of the reinforcing steel. This issue was partially controlled during the 1970s with the incorporation of the epoxy-coating protection system. However, research later demonstrated that the smooth surface resulting from the epoxy-coating application reduces most of the friction between the rebar and the surrounding concrete. Consequently, forces acting on the rib faces are reconfigured in such a way that the radial components increase, triggering the early development of cracks. To mitigate both the reduction of bonding and the formation of cracks, the Illinois Department of Transportation proposed a new type of coated bars: textured epoxy-coated (TEC) bars. Over the last few years, different projects have been executed to understand and improve the characteristics of TEC rebars. This report is a continuation of research performed at the University of Illinois Urbana-Champaign to evaluate the bond behavior of TEC bars. The experimental program starts by characterizing, qualitatively and quantitatively, the roughness of the TEC rebars. Next, their bond-slip interaction embedded in concrete is evaluated through pull-out tests. Finite element models of these tests are developed to validate the behavior observed as the textured reinforcement loses anchorage with concrete. Based on these results, the experimental program then aims to study the impact of the drying shrinkage, temperature change, and flexural demands on two large-scale bridge deck specimens reinforced, individually, with TEC and standard epoxy-coated bars. The results collected from both specimens using digital image correlation and strain gauges are compared to explore the differences exhibited by the traditional and the new type of reinforcement coatings in terms of stress distribution in bridge decks. Finally, given the specialized equipment and time-consuming procedure needed to calculate the roughness parameters of TEC bars, an empirical, weight-based approach is developed as a rapid method for assessing the rebars’ roughness on-site.
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Feng, Zhangxi, Miroslav Zecevic, and Ricardo Lebensohn. Surface roughness in polycrystalline copper under cyclic thermal loading: FFT-based thermomechanical modelling with experimental verification for accelerator applications. Office of Scientific and Technical Information (OSTI), August 2022. http://dx.doi.org/10.2172/1879365.

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6

White, Edward B. Experiments in Transient Growth and Roughness-Induced Bypass Transition. Fort Belvoir, VA: Defense Technical Information Center, March 2005. http://dx.doi.org/10.21236/ada433231.

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7

Al-Qadi, Imad, Jaime Hernandez, Angeli Jayme, Mojtaba Ziyadi, Erman Gungor, Seunggu Kang, John Harvey, et al. The Impact of Wide-Base Tires on Pavement—A National Study. Illinois Center for Transportation, October 2021. http://dx.doi.org/10.36501/0197-9191/21-035.

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Researchers have been studying wide-base tires for over two decades, but no evidence has been provided regarding the net benefit of this tire technology. In this study, a comprehensive approach is used to compare new-generation wide-base tires (NG-WBT) with the dual-tire assembly (DTA). Numerical modeling, prediction methods, experimental measurements, and environmental impact assessment were combined to provide recommendations about the use of NG-WBT. A finite element approach, considering variables usually omitted in the conventional analysis of flexible pavement was utilized for modeling. Five hundred seventy-six cases combining layer thickness, material properties, tire load, tire inflation pressure, and pavement type (thick and thin) were analyzed to obtained critical pavement responses. A prediction tool, known as ICT-Wide, was developed based on artificial neural networks to obtain critical pavement responses in cases outside the finite element analysis matrix. The environmental impacts were determined using life cycle assessment. Based on the bottom-up fatigue cracking, permanent deformation, and international roughness index, the life cycle energy consumption, cost, and green-house gas (GHG) emissions were estimated. To make the outcome of this research effort useful for state departments of transportation and practitioners, a modification to AASHTOWare is proposed to account for NG-WBT. The revision is based on two adjustment factors, one accounting for the discrepancy between the AASHTOware approach and the finite element model of this study, and the other addressing the impact of NG-WBT.
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Saric, William S. Flight Experiments on Swept-Wing Roughness Receptivity: Validation Data for Modeling and Computations. Fort Belvoir, VA: Defense Technical Information Center, September 2010. http://dx.doi.org/10.21236/ada564004.

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9

White, Edward B. Experiments on the Receptivity of Transient Disturbances to Surface Roughness and Freestream Turbulence. Fort Belvoir, VA: Defense Technical Information Center, January 2008. http://dx.doi.org/10.21236/ada475923.

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White, Edward B. Continuing Experiments on the Receptivity of Transient Disturbances to Surface Roughness and Freestream Turbulence. Fort Belvoir, VA: Defense Technical Information Center, September 2008. http://dx.doi.org/10.21236/ada589753.

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