The Experts below are selected from a list of 87 Experts worldwide ranked by ideXlab platform
H S Cheng - One of the best experts on this subject based on the ideXlab platform.
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tribological behavior of sic whisker al2o3 composites against carburized 8620 steel in lubricated sliding
Journal of the American Ceramic Society, 1991Co-Authors: M E Fine, H S ChengAbstract:Mineral oil lubricated sliding tests of Sic-whisker (SiCw,)/A1203 composites and monolithic alumina against carburized 8620 steel were conducted on a cylinder-on-cylinder machine. The wear rate of the composites was one or two orders of magnitude less than that of pure alumina. Hot-pressed 25 wt% SiCw,/A1203 composite had a lower wear rate than sintered and HIPed 7.5 wt% SiC/Al2O3 composite under the same conditions. The weight loss of the steel Mating Ring against the 25 wt% SiCw, composite was a factor of four lower than against the 7.5 wt% SiCw, composite, but the former was a factor of 50 to 60 less than that against pure alumina. The composites showed lower friction coefficients than alumina duRing the run-in stage. The friction coefficients decreased with initial wear. The steady-state friction coefficient decreased with increasing load up to 500 N for hot-pressed 25 wt% SiC,/Al203 composite. Further, SEM observation showed much less microfracture in composites than in alumina. EDAX analysis revealed less Fe transfer from the steel Ring to the composites than to pure alumina. Wear by microfracture and by adhesion in composites was suggested to be suppressed by SIC whiskers. This in turn reduced wear of the steel because of the generation of fewer hard particles.
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Tribological Behavior of SiC‐Whisker/Al2O3 Composites against Carburized 8620 Steel in Lubricated Sliding
Journal of the American Ceramic Society, 1991Co-Authors: Haiyan Liu, M E Fine, H S ChengAbstract:Mineral oil lubricated sliding tests of Sic-whisker (SiCw,)/A1203 composites and monolithic alumina against carburized 8620 steel were conducted on a cylinder-on-cylinder machine. The wear rate of the composites was one or two orders of magnitude less than that of pure alumina. Hot-pressed 25 wt% SiCw,/A1203 composite had a lower wear rate than sintered and HIPed 7.5 wt% SiC/Al2O3 composite under the same conditions. The weight loss of the steel Mating Ring against the 25 wt% SiCw, composite was a factor of four lower than against the 7.5 wt% SiCw, composite, but the former was a factor of 50 to 60 less than that against pure alumina. The composites showed lower friction coefficients than alumina duRing the run-in stage. The friction coefficients decreased with initial wear. The steady-state friction coefficient decreased with increasing load up to 500 N for hot-pressed 25 wt% SiC,/Al203 composite. Further, SEM observation showed much less microfracture in composites than in alumina. EDAX analysis revealed less Fe transfer from the steel Ring to the composites than to pure alumina. Wear by microfracture and by adhesion in composites was suggested to be suppressed by SIC whiskers. This in turn reduced wear of the steel because of the generation of fewer hard particles.
M E Fine - One of the best experts on this subject based on the ideXlab platform.
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tribological behavior of sic whisker al2o3 composites against carburized 8620 steel in lubricated sliding
Journal of the American Ceramic Society, 1991Co-Authors: M E Fine, H S ChengAbstract:Mineral oil lubricated sliding tests of Sic-whisker (SiCw,)/A1203 composites and monolithic alumina against carburized 8620 steel were conducted on a cylinder-on-cylinder machine. The wear rate of the composites was one or two orders of magnitude less than that of pure alumina. Hot-pressed 25 wt% SiCw,/A1203 composite had a lower wear rate than sintered and HIPed 7.5 wt% SiC/Al2O3 composite under the same conditions. The weight loss of the steel Mating Ring against the 25 wt% SiCw, composite was a factor of four lower than against the 7.5 wt% SiCw, composite, but the former was a factor of 50 to 60 less than that against pure alumina. The composites showed lower friction coefficients than alumina duRing the run-in stage. The friction coefficients decreased with initial wear. The steady-state friction coefficient decreased with increasing load up to 500 N for hot-pressed 25 wt% SiC,/Al203 composite. Further, SEM observation showed much less microfracture in composites than in alumina. EDAX analysis revealed less Fe transfer from the steel Ring to the composites than to pure alumina. Wear by microfracture and by adhesion in composites was suggested to be suppressed by SIC whiskers. This in turn reduced wear of the steel because of the generation of fewer hard particles.
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Tribological Behavior of SiC‐Whisker/Al2O3 Composites against Carburized 8620 Steel in Lubricated Sliding
Journal of the American Ceramic Society, 1991Co-Authors: Haiyan Liu, M E Fine, H S ChengAbstract:Mineral oil lubricated sliding tests of Sic-whisker (SiCw,)/A1203 composites and monolithic alumina against carburized 8620 steel were conducted on a cylinder-on-cylinder machine. The wear rate of the composites was one or two orders of magnitude less than that of pure alumina. Hot-pressed 25 wt% SiCw,/A1203 composite had a lower wear rate than sintered and HIPed 7.5 wt% SiC/Al2O3 composite under the same conditions. The weight loss of the steel Mating Ring against the 25 wt% SiCw, composite was a factor of four lower than against the 7.5 wt% SiCw, composite, but the former was a factor of 50 to 60 less than that against pure alumina. The composites showed lower friction coefficients than alumina duRing the run-in stage. The friction coefficients decreased with initial wear. The steady-state friction coefficient decreased with increasing load up to 500 N for hot-pressed 25 wt% SiC,/Al203 composite. Further, SEM observation showed much less microfracture in composites than in alumina. EDAX analysis revealed less Fe transfer from the steel Ring to the composites than to pure alumina. Wear by microfracture and by adhesion in composites was suggested to be suppressed by SIC whiskers. This in turn reduced wear of the steel because of the generation of fewer hard particles.
Michael M. Khonsari - One of the best experts on this subject based on the ideXlab platform.
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Thermal performance of mechanical seals with textured side-wall
Tribology International, 2012Co-Authors: Nian Xiao, Michael M. KhonsariAbstract:Abstract Experimental measurements and numerical simulations are presented to show the effectiveness of cooling of a mechanical seal's active surface by means of cylindrically shaped dimples engraved circumferentially on the outside diameter of the Mating Ring. The working fluid is propylene glycol solution (70% in water by volume) and the flush rate is 107 cm 3 /s. A commercially available CFD code (FLUENT) is employed to numerically confirm the experimental measurements, and the numerical and experimental results are in agreement. Results of this study demonstrate the heat augmentation effectiveness of surface texture techniques on the mechanical seals.
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Numerical Simulations of the Flow Field Around the Rings of Mechanical Seals
Journal of Tribology, 2006Co-Authors: Zhaogao Luan, Michael M. KhonsariAbstract:The flow inside a seal chamber as induced by the influx of the flush fluid and the rotation of the primary Ring is analyzed. The 3-D flow characteristic around the Mating Ring and the rotating Ring are predicted by solving the Navier-Stokes equations in cylindrical coordinates. For this purpose, the pressure correction method was used in conjunction with the SIMPLE algorithm. A series of numerical solutions is presented that show the flow mechanism within the gap between the Rings and the gland. The implication of the flow characteristic on the cooling of the Rings is discussed.
Haiyan Liu - One of the best experts on this subject based on the ideXlab platform.
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Tribological Behavior of SiC‐Whisker/Al2O3 Composites against Carburized 8620 Steel in Lubricated Sliding
Journal of the American Ceramic Society, 1991Co-Authors: Haiyan Liu, M E Fine, H S ChengAbstract:Mineral oil lubricated sliding tests of Sic-whisker (SiCw,)/A1203 composites and monolithic alumina against carburized 8620 steel were conducted on a cylinder-on-cylinder machine. The wear rate of the composites was one or two orders of magnitude less than that of pure alumina. Hot-pressed 25 wt% SiCw,/A1203 composite had a lower wear rate than sintered and HIPed 7.5 wt% SiC/Al2O3 composite under the same conditions. The weight loss of the steel Mating Ring against the 25 wt% SiCw, composite was a factor of four lower than against the 7.5 wt% SiCw, composite, but the former was a factor of 50 to 60 less than that against pure alumina. The composites showed lower friction coefficients than alumina duRing the run-in stage. The friction coefficients decreased with initial wear. The steady-state friction coefficient decreased with increasing load up to 500 N for hot-pressed 25 wt% SiC,/Al203 composite. Further, SEM observation showed much less microfracture in composites than in alumina. EDAX analysis revealed less Fe transfer from the steel Ring to the composites than to pure alumina. Wear by microfracture and by adhesion in composites was suggested to be suppressed by SIC whiskers. This in turn reduced wear of the steel because of the generation of fewer hard particles.
Nian Xiao - One of the best experts on this subject based on the ideXlab platform.
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Improving thermal performance of mechanical seals via surface textuRing
Proceedings of the Institution of Mechanical Engineers Part J: Journal of Engineering Tribology, 2014Co-Authors: Nian Xiao, Mm KhonsariAbstract:The effectiveness of using textured surfaces on the mechanical face seal Mating Ring to enhance thermal performance of seal Rings was experimentally demonstrated in a recent paper.1 Further experiments show that the dimples engraved on the primary Ring outer surface can also reduce the Rings’ contact face temperature. Interestingly, however, when both Rings are treated, the seal sets just show slightly better temperature reduction than a single textured Ring. An appropriate heat transfer augmentation coefficient is defined and used to estimate the surface heat transfer coefficient of textured Mating Ring. The surface heat transfer coefficient of textured primary Ring is also estimated. To understand the nature of heat transfer of surface texture, a computational fluid dynamics (CFD) analysis was carried out using ANSYS Fluent. The turbulent Reynolds stress model was adopted in the analysis with liquid hydrocarbon as the working fluid. The flow structure within a dimple, which demonstrates the working mech...
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Thermal performance of mechanical face seal with built-in heat pipe
Proceedings of the Institution of Mechanical Engineers Part J: Journal of Engineering Tribology, 2013Co-Authors: Nian Xiao, Mm KhonsariAbstract:Performance of a prototype mechanical face seal with built-in heat pipe is experimentally evaluated. The results demonstrate the feasibility of using phase change to remove frictional heating and thus reduce interfacial temperature. In this design, the heat pipe is integrated into the seal Mating Ring and there is no need to modify the gland design or the flush arrangement. The experimental results show that by means of phase change, this design is capable of significantly reducing the temperature at the seal Rings’ interface. To gain insight into the heat transfer enhancement of the heat pipe Mating Ring, a one-dimensional steady-state heat transfer analysis is applied to predict the Ring wall temperature distribution and to estimate the saturated vapor temperature. The effective thermal conductivity of heat pipe Mating Ring is estimated. These results of prediction are in good agreement with experimental measurements.
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Thermal performance of mechanical seals with textured side-wall
Tribology International, 2012Co-Authors: Nian Xiao, Michael M. KhonsariAbstract:Abstract Experimental measurements and numerical simulations are presented to show the effectiveness of cooling of a mechanical seal's active surface by means of cylindrically shaped dimples engraved circumferentially on the outside diameter of the Mating Ring. The working fluid is propylene glycol solution (70% in water by volume) and the flush rate is 107 cm 3 /s. A commercially available CFD code (FLUENT) is employed to numerically confirm the experimental measurements, and the numerical and experimental results are in agreement. Results of this study demonstrate the heat augmentation effectiveness of surface texture techniques on the mechanical seals.