scholarly journals Effects of Friction Plate Hardness and Surface Orientation on the Frictional Properties of Cereal Grain

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Zdzisław Kaliniewicz ◽  
Krzysztof Jadwisieńczak ◽  
Zbigniew Żuk ◽  
Stanisław Konopka ◽  
Adam Frączyk ◽  
...  
Keyword(s):  
Surface Characteristics ◽  
Static Friction ◽  
Surface Orientation ◽  
Frictional Properties ◽  
Parallel Surface ◽  
Cereal Species ◽  
Cereal Grain ◽  
Friction Plate ◽  
Hardness Values ◽  
Average Angle

The objective of this study was to evaluate the effects of the friction plate hardness and surface orientation of a friction plate on the angle and coefficient of static friction of cereal kernels. The angle of static friction of kernels representing four major cereal species was measured on six friction plates with different hardness. The friction plates were placed in position where their surface orientation was perpendicular or parallel relative to their inclination tilt. The experimental material comprised the so-called flat seed units, where each unit consisted of three spaced kernels. The angle of static friction of every flat seed unit was measured with a dedicated device in three replications, and average values of that angle were calculated. The kernels’ angle of static friction varied considerably from 13° to 33° within the analyzed range of changes in the surface characteristics of friction plates. The average angle of static friction was influenced mainly by the surface orientation of the friction plate that came into contact with cereal kernels. The angle of static friction was 17.5% to 56.5% higher when the friction plate had perpendicular rather than parallel surface orientation. The frictional properties of kernels were less influenced by plate hardness, and clear relationships were not observed in this respect. The kernels’ coefficient of static friction remained fairly constant within the analyzed range of plate hardness values, and it was estimated at 0.4 on plates with a perpendicular surface orientation and at 0.3 on plates with a parallel surface orientation.

Orientation Effects on Flow Boiling Silicon Nanowire Microchannels

2016 ◽  
Author(s):  
Tamanna Alam ◽  
Wenming Li ◽  
Fanghao Yang ◽  
Jamil Khan ◽  
Chen Li
Keyword(s):  
Heat Transfer ◽  
Mass Flux ◽  
Flow Boiling ◽  
Silicon Nanowire ◽  
Heating Surface ◽  
Surface Characteristics ◽  
Nucleate Boiling ◽  
Surface Orientation ◽  
Space Applications ◽  
Thin Film Evaporation

Flow boiling in Silicon Nanowire microchannel enhances heat transfer performance, CHF and reduces pressure drop compared to Plainwall microchannel. It is revealed by earlier studies that promoted nucleate boiling, liquid rewetting and enhanced thin film evaporation are the primary reasons behind these significant performance enchantments. Although flow regime plays a significant role to characterize the flow boiling Silicon Nanowire microchannel performances; surface characteristics, hydrodynamic phenomena, bubble contact angle and surface orientation are also some of the major influencing parameters in system performances. More importantly, effect of orientation (effect of gravity) draws a great attention in establishing the viability of flow boiling in microchannels in space applications. In this study, the effects of heating surface orientation in flow boiling Silicon Nanowire microchannels have been investigated to reveal the underlying heat transfer phenomena and also to discover the applicability of this system in space applications. Comparison between Nanowire and Plainwall microchannels have been performed by experimental and visual studies. Experiments were conducted in a forced convection loop with deionized water at mass flux range of 100kg/m2s – 600kg/m2s. Micro devices consist of five parallel straight microchannels with Nanowire and without Nanowire (Plainwall) (200μm × 250μm × 10mm) were used to investigate the effects of orientation. Two different orientations were used to perform the test: upward facing (0° Orientation) and downward facing (180° Orientation). Results for Plainwall show sensitivity to orientation and mass flux, whereas, little effects of mass flux and orientation have been observed for Nanowire configuration.

The Simulation Research of Dual Clutch Transmission's Starting Process Based on Dynamic Friction Coefficient

2013 ◽  
Vol 401-403 ◽  
pp. 320-325
Author(s):  
Ming Ming Qiu ◽  
Han Zhao ◽  
Fa Ming Sha
Keyword(s):  
Friction Coefficient ◽  
Vibration Analysis ◽  
Working Condition ◽  
Static Friction ◽  
Dynamic Friction ◽  
Simulation Research ◽  
Static Friction Coefficient ◽  
Dynamic Friction Coefficient ◽  
Friction Plate ◽  
Starting Process

Introduce the dynamic friction coefficient of clutch friction plate. Establish Mathematical model of starting process, carried out vibration analysis for frictional sliding process systematically, validated the analysis using Matlab/simulink software. Meanwhile, compared with the starting process by static friction coefficient. The results show that using dynamic friction coefficient to analyse starting process conforms to the actual working condition.

scholarly journals Influence of Steel Plate Roughness on the Frictional Properties of Cereal Kernels

2018 ◽  
Author(s):  
Zdzisław Kaliniewicz ◽  
Zbigniew Żuk ◽  
Zbigniew Krzysiak
Keyword(s):  
Surface Roughness ◽  
Steel Plate ◽  
Friction Angle ◽  
External Friction ◽  
Adhesive Tape ◽  
Frictional Properties ◽  
Grain Processing ◽  
Experimental Variant ◽  
Optimal Surface ◽  
Friction Plate

The aim of this study was to determine the correlation between the external friction angle of cereal kernels and the roughness of a steel friction plate. The experiment was performed on the kernels of five principal cereals: wheat, rye, barley, oats and triticale. Flat seed units composed of three spaced kernels joined by adhesive tape were analyzed in each experimental variant. The external friction angle of flat seed units was determined on 9 steel friction plates with different roughness. Measurements were performed in 3 replications with a photosensor device which registered the external friction angle of cereal kernels. On friction plates with surface roughness Ra=0.36 to Ra=6.72, the average values of the angle of external friction ranged from 17.56° in rye kernels to 34.01° in oat kernels. The greatest similarities in the angle of external friction were observed between wheat and triticale kernels, whereas the greatest differences were noted between barley and oat kernels and between barley and triticale kernels. Friction plates made of ST3S steel should be characterized by the lowest surface roughness to minimize energy consumption during grain processing. The optimal surface roughness of steel friction plates was determined at Ra=0.9.

scholarly journals Influence of Steel Plate Roughness on the Frictional Properties of Cereal Kernels

2018 ◽  
Author(s):  
Zdzisław Kaliniewicz ◽  
Zbigniew Żuk ◽  
Zbigniew Krzysiak
Keyword(s):  
Surface Roughness ◽  
Steel Plate ◽  
Friction Angle ◽  
External Friction ◽  
Adhesive Tape ◽  
Frictional Properties ◽  
Grain Processing ◽  
Experimental Variant ◽  
Optimal Surface ◽  
Friction Plate

The aim of this study was to determine the correlation between the external friction angle of cereal kernels and the roughness of a steel friction plate. The experiment was performed on the kernels of five principal cereals: wheat, rye, barley, oats and triticale. Flat seed units composed of three spaced kernels joined by adhesive tape were analyzed in each experimental variant. The external friction angle of flat seed units was determined on 9 steel friction plates with different roughness. Measurements were performed in 3 replications with a photosensor device which registered the external friction angle of cereal kernels. On friction plates with surface roughness Ra=0.36 to Ra=6.72, the average values of the angle of external friction ranged from 17.56° in rye kernels to 34.01° in oat kernels. The greatest similarities in the angle of external friction were observed between wheat and triticale kernels, whereas the greatest differences were noted between barley and oat kernels and between barley and triticale kernels. Friction plates made of ST3S steel should be characterized by the lowest surface roughness to minimize energy consumption during grain processing. The optimal surface roughness of steel friction plates was determined at Ra=0.9.

scholarly journals Frictional Anisotropy of 3D-Printed Fault Surfaces

2021 ◽  
Vol 9 ◽  
Author(s):  
Tom Vincent-Dospital ◽  
Alain Steyer ◽  
François Renard ◽  
Renaud Toussaint
Keyword(s):  
Friction Coefficient ◽  
3D Printing ◽  
Mechanical Stability ◽  
Spatial Scales ◽  
Static Friction ◽  
Spatial Anisotropy ◽  
Frictional Properties ◽  
Average Coefficient ◽  
3D Printed ◽  
Frictional Slip

The surface morphology of faults controls the spatial anisotropy of their frictional properties and hence their mechanical stability. Such anisotropy is only rarely studied in seismology models of fault slip, although it might be paramount to understand the seismic rupture in particular areas, notably where slip occurs in a direction different from that of the main striations of the fault. To quantify how the anisotropy of fault surfaces affects the friction coefficient during sliding, we sheared synthetic fault planes made of plaster of Paris. These fault planes were produced by 3D-printing real striated fault surfaces whose 3D roughness was measured in the field at spatial scales from millimeters to meters. Here, we show how the 3D-printing technology can help for the study of frictional slip. The results show that fault anisotropy controls the coefficient of static friction, with μS//, the friction coefficient along the striations being three to four times smaller than μS⊥, the friction coefficient along the orientation perpendicular to the striations. This is true both at the meter and the millimeter scales. The anisotropy in friction and the average coefficient of static friction are also shown to decrease with the normal stress applied to the faults, as a result of the increased surface wear under increased loading.

Effects of the KMnO4/Salt Shrinkproofing Treatment on the Frictional Properties of Wool Fibers

1969 ◽  
Vol 39 (8) ◽  
pp. 710-721 ◽  
Author(s):  
K. Rachel Makinson
Keyword(s):  
Aqueous Media ◽  
Static Friction ◽  
Experimental Conditions ◽  
Frictional Properties ◽  
Wool Fibers

Following on the observation that the KMnO4/salt shrinkproofing process attacks the scales on the intrados of the crimp of wool fibers preferentially, the “static” friction of wool fibers over polished horn in aqueous media has been measured by the standard capstan method under conditions chosen to ensure that some contact is made with the intrados of the crimp. It has been found that the treatment causes a large increase in the with-scale friction and in some circumstances a decrease in the frictional difference. When the proportion of contact with the intrados of the crimp is reduced, these effects become much smaller. Both types of frictional change are the result of degradation of the material inside the scale-cells, which makes the scales, when wet, softer and less elastic than the scales of untreated fibers. Experimental conditions determine whether this softening is expressed as an increase in with-scale friction or as a decrease in the frictional difference.

IN VITRO STUDY AND MECHANICAL CHARACTERISTICS OF DENTAL IMPLANTS MADE OF VARIOUS MATERIALS AND FABRICATION METHODS

2021 ◽  
Vol 21 (01) ◽  
pp. 2150004
Author(s):  
MEHDI MASHHADI ◽  
REZA HAMZELOO ◽  
MEGHDAD FALLAH
Keyword(s):  
Dental Implants ◽  
Surface Hardness ◽  
In Vitro Study ◽  
Surface Characteristics ◽  
Topology Design ◽  
In Vitro Tests ◽  
Implant Surface ◽  
Experimental Surface ◽  
Hardness Values

Selecting materials and alloys, fabrication methods, surface characteristics and coatings, and topology design, all affect the mechanical properties, biocompatibility, and functionality of dental implants. The success in embedding implants in mouth and improving biocompatibility and consequently useful life of implants depends directly on proper adhesion of tissue to implant surface of a biocompatible alloy. In this research, experimental surface hardness and in vitro tests are carried out on samples with different alloys and different manufacturing methods. Various fabrication techniques, such as machining and 3D printing (Selective laser melting (SLM)), are considered for steel and titanium specimens. Results show that the hardness values of specimens made by the SLM method are higher than machined samples about 8% and also stainless steels samples have higher hardness than titanium specimens. A comparison of scanning electron microscopy (SEM) surface pictures indicates that applying modern fabrication methods for production which includes SLM improves the performance of implants in terms of mechanical and biocompatibility by increasing cell adhesion up to 21 times. In addition, results indicate that titanium alloys have almost 13% higher adhesion property than stainless steel and generally exhibit a higher balance of adhesion and cell growth.

Frictional Properties of Tread-Type Compounds on ICE

1949 ◽  
Vol 22 (3) ◽  
pp. 863-877 ◽  
Author(s):  
F. S. Conant ◽  
J. L. Dum ◽  
C. M. Cox
Keyword(s):  
Laboratory Test ◽  
Static Friction ◽  
Principal Factor ◽  
Test Method ◽  
Frictional Properties ◽  
Laboratory Test Method ◽  
Base Polymer ◽  
Fair Degree

Abstract The laboratory test method described is capable of indicating with a fair degree of accuracy the tractive ability of a tire tread compound on ice. Coefficients of both dynamic and static friction are important in determining the resistance to slide of a tire. The base polymer in a tread compound is the principal factor affecting the coefficients of friction. Among compounds based on different polymers, the coefficients of friction on ice are not closely related to either the stiffness or hardness of the stock or to its hysteresis. The coefficients of friction of stocks based on a single polymer, however, are greatly influenced by the type and amount of softener and by the type and amount of black.

scholarly journals Determination of Selected Moisture -Dependent Physical and Frictional Properties of Shelled Egusi Melon (Citrullus lanatus Thunb.)

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Adesola A Satimehin ◽  
Terseer M Akaayar
Keyword(s):  
Internal Friction ◽  
Bulk Density ◽  
Citrullus Lanatus ◽  
Static Friction ◽  
Angle Of Repose ◽  
Test Material ◽  
True Density ◽  
Efficient Design ◽  
Frictional Properties ◽  
Melon Seeds

Physical and frictional properties were determined for shelled (i.e. hulled) seeds of egusi melon (Citrullus lanatus Thunb) at moisture content levels of 11.04, 15.7, 21.03 and 24.78 % dry basis. The physical properties investigated were true density, bulk density and the angle of repose; while the frictional properties were the coefficient of static friction and the coefficient of internal friction.  Densities were determined using the volume displacement method, while the bulk porosity was calculated as a function of the true and bulk densities. The angle of repose was measured using the cylinder method. The coefficient of static friction of melon seeds on the surfaces of plywood, galvanized iron and glass was determined by sliding a cell filled with the seeds on a tilting table overlaid with the test material surfaces. The coefficient and internal angle of friction were determined by means of a shear test apparatus. Within the range of moisture investigated, the true density of shelled melon seeds decreased from 1,264 to 1,239 kg/m3 while its bulk density increased from 668 to 681 kg/m3. The porosity decreased from 47.19 to 45.36 % while the angle of repose increased from 31.0 to 34.9°. The coefficient of friction of shelled melon seeds on the surfaces of glass, galvanised iron and plywood  increased from 0.329 to 0.475, 0.364 to 0.476 and 0.408 to 0.559 respectively. The coefficient and angle of internal friction increased from 0.638 to 0.668 and 32.52 to 33.74°, respectively. These findings are valuable data for efficient design of machines for processing, handling and storage of hulled seeds of egusi melon.

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