Pub Date : 2018-06-01DOI: 10.1177/2397791418802498
M. Hasan, S. M. Shavik, K. F. Rabbi, K. M. Mukut, M. Alam
Investigation of thermal transport characteristics of thin-film liquid evaporation over nanostructured surface has been conducted using molecular dynamics simulation with particular importance on the effects of the nanostructure configuration for different wall–fluid interaction strengths. The nanostructured surface considered herein comprises wall-through rectangular nanoposts placed over a flat wall. Both the substrate and the nanostructure are of platinum while argon is used as the evaporating liquid. Two different wall–fluid interaction strengths have been considered that essentially emulate both hydrophilic and hydrophobic wetting conditions for three different nanostructure configurations. The argon–platinum molecular system is first equilibrated at 90 K and then followed by a sudden increase in the wall temperature at 130 K that induces evaporation of argon laid over it. Comparative effectiveness of heat and mass transfer for different surface wetting conditions has been studied by calculating the wall heat flux and evaporative mass flux. The results obtained in this study show that heat transfer occurs more easily in cases of nanostructured surfaces than in case of flat surface. Difference in behavior of argon molecules during and after the evaporation process, that is, wall adsorption characteristics, has been found to depend on the surface wetting condition as well as on presence and configuration of nanostructure. A thermodynamic approach of energy balance shows reasonable agreement with the present molecular dynamics study.
{"title":"Thermal transport during thin-film argon evaporation over nanostructured platinum surface: A molecular dynamics study","authors":"M. Hasan, S. M. Shavik, K. F. Rabbi, K. M. Mukut, M. Alam","doi":"10.1177/2397791418802498","DOIUrl":"https://doi.org/10.1177/2397791418802498","url":null,"abstract":"Investigation of thermal transport characteristics of thin-film liquid evaporation over nanostructured surface has been conducted using molecular dynamics simulation with particular importance on the effects of the nanostructure configuration for different wall–fluid interaction strengths. The nanostructured surface considered herein comprises wall-through rectangular nanoposts placed over a flat wall. Both the substrate and the nanostructure are of platinum while argon is used as the evaporating liquid. Two different wall–fluid interaction strengths have been considered that essentially emulate both hydrophilic and hydrophobic wetting conditions for three different nanostructure configurations. The argon–platinum molecular system is first equilibrated at 90 K and then followed by a sudden increase in the wall temperature at 130 K that induces evaporation of argon laid over it. Comparative effectiveness of heat and mass transfer for different surface wetting conditions has been studied by calculating the wall heat flux and evaporative mass flux. The results obtained in this study show that heat transfer occurs more easily in cases of nanostructured surfaces than in case of flat surface. Difference in behavior of argon molecules during and after the evaporation process, that is, wall adsorption characteristics, has been found to depend on the surface wetting condition as well as on presence and configuration of nanostructure. A thermodynamic approach of energy balance shows reasonable agreement with the present molecular dynamics study.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"43 1","pages":"83 - 91"},"PeriodicalIF":6.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86887887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-06-01DOI: 10.1177/2397791418782030
P. Rana, N. Shukla, O. Bég, A. Kadir, Bani Singh
This article investigates the combined influence of nonlinear radiation, Stefan blowing and chemical reactions on unsteady electro-magneto-hydrodynamic stagnation-point flow of a nanofluid from a horizontal stretching sheet. Both electrical and magnetic body forces are considered. In addition, the effects of velocity slip, thermal slip and mass slip are considered at the boundaries. An analytical method named as homotopy analysis method is applied to solve the non-dimensional system of nonlinear partial differential equations which are obtained by applying similarity transformations on governing equations. The effects of emerging parameters such as Stefan blowing parameter, electric parameter and magnetic parameter on the important physical quantities are presented graphically. In addition, an entropy generation analysis is provided in this article for thermal optimization. The flow is observed to be accelerated both with increasing magnetic field and electrical field. Entropy generation number is markedly enhanced with greater magnetic field, electrical field and Reynolds number, whereas it is reduced with increasing chemical reaction parameter.
{"title":"Unsteady electromagnetic radiative nanofluid stagnation-point flow from a stretching sheet with chemically reactive nanoparticles, Stefan blowing effect and entropy generation","authors":"P. Rana, N. Shukla, O. Bég, A. Kadir, Bani Singh","doi":"10.1177/2397791418782030","DOIUrl":"https://doi.org/10.1177/2397791418782030","url":null,"abstract":"This article investigates the combined influence of nonlinear radiation, Stefan blowing and chemical reactions on unsteady electro-magneto-hydrodynamic stagnation-point flow of a nanofluid from a horizontal stretching sheet. Both electrical and magnetic body forces are considered. In addition, the effects of velocity slip, thermal slip and mass slip are considered at the boundaries. An analytical method named as homotopy analysis method is applied to solve the non-dimensional system of nonlinear partial differential equations which are obtained by applying similarity transformations on governing equations. The effects of emerging parameters such as Stefan blowing parameter, electric parameter and magnetic parameter on the important physical quantities are presented graphically. In addition, an entropy generation analysis is provided in this article for thermal optimization. The flow is observed to be accelerated both with increasing magnetic field and electrical field. Entropy generation number is markedly enhanced with greater magnetic field, electrical field and Reynolds number, whereas it is reduced with increasing chemical reaction parameter.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"13 1","pages":"69 - 82"},"PeriodicalIF":6.0,"publicationDate":"2018-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84246267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-05-28DOI: 10.1177/2397791418776520
B. Jha, M. Oni
This study examines the role of magnetic field on fully developed mixed convection flow of heat generating/absorbing fluid in a vertical micro-concentric annulus with velocity slip and temperature jump at the surfaces of the cylinders. Exact solution of momentum and energy equations are obtained separately in terms of Bessel’s function and modified Bessel’s function of first and second kind. The solutions obtained are graphically represented and the effects of pertinent parameters on flow formation and skin-friction are investigated in details. Results show that the role of magnetic field is to decrease fluid velocity as well as skin-friction at the outer surface of inner cylinder. In addition, reverse flow formation can be controlled by increasing magnetic field strength.
{"title":"Role of magnetic field on mixed convective flow between two concentric microtubes with heat generation/absorption: An exact solution","authors":"B. Jha, M. Oni","doi":"10.1177/2397791418776520","DOIUrl":"https://doi.org/10.1177/2397791418776520","url":null,"abstract":"This study examines the role of magnetic field on fully developed mixed convection flow of heat generating/absorbing fluid in a vertical micro-concentric annulus with velocity slip and temperature jump at the surfaces of the cylinders. Exact solution of momentum and energy equations are obtained separately in terms of Bessel’s function and modified Bessel’s function of first and second kind. The solutions obtained are graphically represented and the effects of pertinent parameters on flow formation and skin-friction are investigated in details. Results show that the role of magnetic field is to decrease fluid velocity as well as skin-friction at the outer surface of inner cylinder. In addition, reverse flow formation can be controlled by increasing magnetic field strength.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"207 1","pages":"59 - 67"},"PeriodicalIF":6.0,"publicationDate":"2018-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82825009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-04-12DOI: 10.1177/2397791418768576
A. Ghasemi, Komeil Hosseinpour, M. Mohandes
In this research, the effects of multi-walled carbon nanotubes on the distribution of long-term creep strains in thick-walled multi-walled carbon nanotube/fiber/polymer three-phase laminated composites are studied. In the first step, micromechanical models are developed to calculate the elastic properties of multi-walled carbon nanotube/vinylester and multi-walled carbon nanotube/E-glass fiber/vinylester composites. Using classical lamination plate theory, equilibrium and compatibility equations and strain–displacement relations, the distribution of effective stresses is considered. Moreover, utilizing Schapery single-integral model for nonlinear viscoelastic materials, Prandtl–Reuss relations and Mendelson’s approximation method, not only the distribution of circumferential and radial strains is investigated but also the effects of fiber orientation and weight fraction (wt.%) of the multi-walled carbon nanotubes on the way of distribution are studied. The results demonstrated that the addition of the multi-walled carbon nanotube to the vinylester can reduce absolute values of the radial and circumferential creep strains and dimensionless effective stresses. Moreover, most reduction occurred in the inner wall of the cylindrical shell when fiber orientation was α = 90°.
在本研究中，研究了多壁碳纳米管对厚壁多壁碳纳米管/纤维/聚合物三相层合复合材料长期蠕变应变分布的影响。首先，建立了微力学模型，计算了多壁碳纳米管/乙烯基材料和多壁碳纳米管/ e -玻璃纤维/乙烯基材料的弹性性能。利用经典层合板理论、平衡相容方程和应变-位移关系，研究了层合板的有效应力分布。此外，利用非线性粘弹性材料的Schapery单积分模型、Prandtl-Reuss关系和Mendelson近似方法，研究了多壁碳纳米管的周向和径向应变分布，以及纤维取向和重量分数(wt.%)对多壁碳纳米管分布方式的影响。结果表明，在乙烯基材料中加入多壁碳纳米管可以降低其径向和周向蠕变应变的绝对值以及无因次有效应力。当纤维取向为α = 90°时，最大的衰减发生在圆柱壳的内壁。
{"title":"Modeling creep behavior of carbon nanotube/fiber/polymer composite cylinders","authors":"A. Ghasemi, Komeil Hosseinpour, M. Mohandes","doi":"10.1177/2397791418768576","DOIUrl":"https://doi.org/10.1177/2397791418768576","url":null,"abstract":"In this research, the effects of multi-walled carbon nanotubes on the distribution of long-term creep strains in thick-walled multi-walled carbon nanotube/fiber/polymer three-phase laminated composites are studied. In the first step, micromechanical models are developed to calculate the elastic properties of multi-walled carbon nanotube/vinylester and multi-walled carbon nanotube/E-glass fiber/vinylester composites. Using classical lamination plate theory, equilibrium and compatibility equations and strain–displacement relations, the distribution of effective stresses is considered. Moreover, utilizing Schapery single-integral model for nonlinear viscoelastic materials, Prandtl–Reuss relations and Mendelson’s approximation method, not only the distribution of circumferential and radial strains is investigated but also the effects of fiber orientation and weight fraction (wt.%) of the multi-walled carbon nanotubes on the way of distribution are studied. The results demonstrated that the addition of the multi-walled carbon nanotube to the vinylester can reduce absolute values of the radial and circumferential creep strains and dimensionless effective stresses. Moreover, most reduction occurred in the inner wall of the cylindrical shell when fiber orientation was α = 90°.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"22 1","pages":"49 - 58"},"PeriodicalIF":6.0,"publicationDate":"2018-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80789462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-03-01DOI: 10.1177/2397791417744966
Wang Zhiwen, Gong Jinliang, Dong Aimei, Cui Bo
Using equivalent medium theory, surface plasma resonance theory and Fabry–Pérot resonance theory, transmission mechanism of single-layer nanowire polarizer is systematically analyzed. Concept of skin depth is used to explain the effect of grating material on polarization transmission. Two transmission minimum points in the curve of grating period versus transverse magnetic transmission are analyzed quantitatively. Effects of grating duty cycle, height and type on polarization transmission of single-layer nanowire polarizer are also analyzed. The requirements of designing single-layer sub-wavelength metal gratings with good polarization properties are given. The analysis of the transmission mechanism of sub-wavelength metal gratings will be helpful for the design and fabrication of the gratings with good polarization properties.
{"title":"Mechanism analyzation of the effects of grating parameters on polarization transmission of single-layer nanowire gratings","authors":"Wang Zhiwen, Gong Jinliang, Dong Aimei, Cui Bo","doi":"10.1177/2397791417744966","DOIUrl":"https://doi.org/10.1177/2397791417744966","url":null,"abstract":"Using equivalent medium theory, surface plasma resonance theory and Fabry–Pérot resonance theory, transmission mechanism of single-layer nanowire polarizer is systematically analyzed. Concept of skin depth is used to explain the effect of grating material on polarization transmission. Two transmission minimum points in the curve of grating period versus transverse magnetic transmission are analyzed quantitatively. Effects of grating duty cycle, height and type on polarization transmission of single-layer nanowire polarizer are also analyzed. The requirements of designing single-layer sub-wavelength metal gratings with good polarization properties are given. The analysis of the transmission mechanism of sub-wavelength metal gratings will be helpful for the design and fabrication of the gratings with good polarization properties.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"46 1","pages":"41 - 47"},"PeriodicalIF":6.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87793001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-03-01DOI: 10.1177/2397791417744702
M. Nandeppanavar, R. S. Reddy Gorla, S. Shakunthala
In this article, we have discussed the effect of external magnetic field and other governing parameters on the flow and heat transfer in the presence of suspended carbon nanotubes over a flat plate. The governing equations of flow and heat transfer are derived from the Navier–Stokes and Prandtl boundary layer concept. The derived governing equations of flow and energy are non-linear partial differential equation, and these equations are converted into non-linear ordinary differential equations with corresponding boundary conditions using some suitable similarity transformations and are solved numerically using fourth-order Runge–Kutta method with efficient shooting technique. Effects of governing parameters on flow and heat transfer are shown through various graphs and explained with physical interpretation in detail. This study has applications in glass-fiber production and technology. On observing the results of this study, we can conclude that external magnetic field shows opposite behaviors on velocity and temperature and it enhances the rate of heat transfer.
{"title":"Magneto-hydrodynamic Blasius flow and heat transfer from a flat plate in the presence of suspended carbon nanofluids","authors":"M. Nandeppanavar, R. S. Reddy Gorla, S. Shakunthala","doi":"10.1177/2397791417744702","DOIUrl":"https://doi.org/10.1177/2397791417744702","url":null,"abstract":"In this article, we have discussed the effect of external magnetic field and other governing parameters on the flow and heat transfer in the presence of suspended carbon nanotubes over a flat plate. The governing equations of flow and heat transfer are derived from the Navier–Stokes and Prandtl boundary layer concept. The derived governing equations of flow and energy are non-linear partial differential equation, and these equations are converted into non-linear ordinary differential equations with corresponding boundary conditions using some suitable similarity transformations and are solved numerically using fourth-order Runge–Kutta method with efficient shooting technique. Effects of governing parameters on flow and heat transfer are shown through various graphs and explained with physical interpretation in detail. This study has applications in glass-fiber production and technology. On observing the results of this study, we can conclude that external magnetic field shows opposite behaviors on velocity and temperature and it enhances the rate of heat transfer.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"30 1","pages":"31 - 40"},"PeriodicalIF":6.0,"publicationDate":"2018-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88460905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-02-28DOI: 10.1177/2397791418761251
J. McGeough
{"title":"Editorial for JNNN","authors":"J. McGeough","doi":"10.1177/2397791418761251","DOIUrl":"https://doi.org/10.1177/2397791418761251","url":null,"abstract":"","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"25 1","pages":"3 - 3"},"PeriodicalIF":6.0,"publicationDate":"2018-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82742441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-03DOI: 10.1177/2397791417750350
Y. Qin
Increased demands on micro-products and miniaturised systems/devices have been a main driver to the rapid growth of the interest in research in micro- and nano-manufacturing. Currently, micro-manufacturing research is bridging ‘nano-manufacturing’ and ‘macro-manufacturing’ and hence, helping to transform nanotechnology into real-world and affordable products, for which it is developing multi-length scale and multi-materials manufacturing capabilities. It is also playing more roles in helping transforming traditional industry and products to more competitive ones. Nevertheless, besides being shifted from ‘process focus’ to ‘market/product’ driven research and technological developments addressing production capability, product quality, pilot production lines and sustainability, there is clearly a need for micro-manufacturing research to adopt integrated, multidisciplinary approaches to address development-related issues concurrently, in order to shorten the development cycles for product realisation. It is believed that to transfer laboratory processes to industrial applications within much shorter timescales, the associated issues should be addressed with collaborations among different, relevant disciplines. European Union–funded integrated projects have demonstrated such efforts. Product development–centred approaches brought in expertise and resources in product design, material, analysis, testing, tools, machines, automation and manufacturing system integration as well as in life-cycle engineering to address the development needs. At the same time, due to ever updated interests in new products and enabling manufacturing technologies with a view to meeting increased demands from, for example, healthcare, on quality of life, for wealth creation, social engagement and sustainable development, there are new challenges to micro- and nano-manufacturing research, which also suggest tremendous opportunities.
{"title":"Integrated, multidisciplinary approaches for micro-manufacturing research, and new opportunities and challenges to micro-manufacturing","authors":"Y. Qin","doi":"10.1177/2397791417750350","DOIUrl":"https://doi.org/10.1177/2397791417750350","url":null,"abstract":"Increased demands on micro-products and miniaturised systems/devices have been a main driver to the rapid growth of the interest in research in micro- and nano-manufacturing. Currently, micro-manufacturing research is bridging ‘nano-manufacturing’ and ‘macro-manufacturing’ and hence, helping to transform nanotechnology into real-world and affordable products, for which it is developing multi-length scale and multi-materials manufacturing capabilities. It is also playing more roles in helping transforming traditional industry and products to more competitive ones. Nevertheless, besides being shifted from ‘process focus’ to ‘market/product’ driven research and technological developments addressing production capability, product quality, pilot production lines and sustainability, there is clearly a need for micro-manufacturing research to adopt integrated, multidisciplinary approaches to address development-related issues concurrently, in order to shorten the development cycles for product realisation. It is believed that to transfer laboratory processes to industrial applications within much shorter timescales, the associated issues should be addressed with collaborations among different, relevant disciplines. European Union–funded integrated projects have demonstrated such efforts. Product development–centred approaches brought in expertise and resources in product design, material, analysis, testing, tools, machines, automation and manufacturing system integration as well as in life-cycle engineering to address the development needs. At the same time, due to ever updated interests in new products and enabling manufacturing technologies with a view to meeting increased demands from, for example, healthcare, on quality of life, for wealth creation, social engagement and sustainable development, there are new challenges to micro- and nano-manufacturing research, which also suggest tremendous opportunities.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"29 1","pages":"21 - 5"},"PeriodicalIF":6.0,"publicationDate":"2018-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75557146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-01-01DOI: 10.1177/2397791417749700
Mohamed O. Helmy, Ahmed M. R. Fath El-Bab, H. El-Hofy
Over the last few decades, miniaturization has become the key aspect of driving evolution of modern technology. The CO2 laser is an inexpensive, flexible, and fast device for fabricating microfluidic chips. Thermal damages associated with such a process are considered the big challenge for microfluidic device developers. This article evaluates the quality of polymethyl methacrylate microchannels fabricated by the CO2 laser. Experiments were conducted in the air (dry) and underwater by leaving a thin water layer on the top surface of the polymethyl methacrylate substrate. The effect of laser power and scanning speed on performance characteristics, such as the microchannel aspect ratio, surface roughness, and heat-affected zone was studied. Taguchi’s experimental design with grey relational analysis was used for multi-objective optimization of the laser micromachining parameters. Analysis of variance was also employed to determine the most significant control factors that affect the microchannel quality. The results indicated that the cooling effect of the underwater method has a significant effect on decreasing the extent of thermal damage while increasing the aspect ratio. Laser power is the most significant factor on the performance characteristics followed by scanning speed and pulse rate. Grey relational analysis is efficient in selecting the optimum conditions regarding the performance characteristics.
{"title":"Fabrication and characterization of polymethyl methacrylate microchannel using dry and underwater CO2 laser","authors":"Mohamed O. Helmy, Ahmed M. R. Fath El-Bab, H. El-Hofy","doi":"10.1177/2397791417749700","DOIUrl":"https://doi.org/10.1177/2397791417749700","url":null,"abstract":"Over the last few decades, miniaturization has become the key aspect of driving evolution of modern technology. The CO2 laser is an inexpensive, flexible, and fast device for fabricating microfluidic chips. Thermal damages associated with such a process are considered the big challenge for microfluidic device developers. This article evaluates the quality of polymethyl methacrylate microchannels fabricated by the CO2 laser. Experiments were conducted in the air (dry) and underwater by leaving a thin water layer on the top surface of the polymethyl methacrylate substrate. The effect of laser power and scanning speed on performance characteristics, such as the microchannel aspect ratio, surface roughness, and heat-affected zone was studied. Taguchi’s experimental design with grey relational analysis was used for multi-objective optimization of the laser micromachining parameters. Analysis of variance was also employed to determine the most significant control factors that affect the microchannel quality. The results indicated that the cooling effect of the underwater method has a significant effect on decreasing the extent of thermal damage while increasing the aspect ratio. Laser power is the most significant factor on the performance characteristics followed by scanning speed and pulse rate. Grey relational analysis is efficient in selecting the optimum conditions regarding the performance characteristics.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"26 1","pages":"23 - 30"},"PeriodicalIF":6.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85856120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-01DOI: 10.1177/2397791417744706
A. Reddy, P. Krishna, R. Rao
Global requirement for minimum cost, high efficiency, and good grade materials has made a diversion in research from base alloys to composite materials, since the last five decades. In the case of metal matrix composites, aluminium metal matrix composites have been certified and steadily advanced due to properties such as high strength, low density, and high wear resistance. They are widely used in automobile industry, aircraft industry, structural applications, and many other defence systems. Researchers have observed that the addition of nano-size SiCNP reinforcements to aluminium-based matrix yields superior properties and good bonding characteristics between matrix and reinforcements of nanocomposites. Along with silicon carbide particulate primary nano-reinforcements, researchers studied the properties of aluminium metal matrix nanocomposites with the addition of secondary reinforcements. These hybrid nanocomposites exhibited improved wear resistance. This article reviews the fabrication methods, mechanical properties, and tribological properties of aluminium-based hybrid metal matrix nanocomposites.
{"title":"Al/SiCNP and Al/SiCNP/X nanocomposites fabrication and properties: A review","authors":"A. Reddy, P. Krishna, R. Rao","doi":"10.1177/2397791417744706","DOIUrl":"https://doi.org/10.1177/2397791417744706","url":null,"abstract":"Global requirement for minimum cost, high efficiency, and good grade materials has made a diversion in research from base alloys to composite materials, since the last five decades. In the case of metal matrix composites, aluminium metal matrix composites have been certified and steadily advanced due to properties such as high strength, low density, and high wear resistance. They are widely used in automobile industry, aircraft industry, structural applications, and many other defence systems. Researchers have observed that the addition of nano-size SiCNP reinforcements to aluminium-based matrix yields superior properties and good bonding characteristics between matrix and reinforcements of nanocomposites. Along with silicon carbide particulate primary nano-reinforcements, researchers studied the properties of aluminium metal matrix nanocomposites with the addition of secondary reinforcements. These hybrid nanocomposites exhibited improved wear resistance. This article reviews the fabrication methods, mechanical properties, and tribological properties of aluminium-based hybrid metal matrix nanocomposites.","PeriodicalId":44789,"journal":{"name":"Proceedings of the Institution of Mechanical Engineers Part N-Journal of Nanomaterials Nanoengineering and Nanosystems","volume":"30 1","pages":"155 - 172"},"PeriodicalIF":6.0,"publicationDate":"2017-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76325382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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