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Online since: May 2011
Authors: Feng Ji, Yu Chuan Shi
The surface shape of structure plane is closely related with its mechanics property.
At present, the measurement method of the undulating curve includes the laser method and mechanical method.
Conventional mechanical measurement method in wild is mainly to utilize the dial indicator to measure the undulating shape, its measurement precision and tempo of drawing is low, especially to the craft measuring instrument, it is slower.
Parameters of mudstone bedding can be obtained through a small direct shear test for straight and smooth fresh mudstone Conclusion Contact Punching Device has been created independently, it is mechanical, durability, high reliability.
Factors affecting the strength of the structure surface are numerous, including the boundary conditions, loading and so on.
At present, the measurement method of the undulating curve includes the laser method and mechanical method.
Conventional mechanical measurement method in wild is mainly to utilize the dial indicator to measure the undulating shape, its measurement precision and tempo of drawing is low, especially to the craft measuring instrument, it is slower.
Parameters of mudstone bedding can be obtained through a small direct shear test for straight and smooth fresh mudstone Conclusion Contact Punching Device has been created independently, it is mechanical, durability, high reliability.
Factors affecting the strength of the structure surface are numerous, including the boundary conditions, loading and so on.
Online since: December 2014
Authors: Hong Bo Zhang, Donald J. Bergstrom, Bing Zhang, Wen Jun Zhang, Lei Lei
Bergstrom1,c , Bing Zhang3,d
and Wenjun Zhang1,3,e
1Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada
2Complex and Intelligent Systems Center, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China
3Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada
aleileiearth@gmail.com, bhbzhang@ecust.edu.cn, cdon.bergstrom@usask.ca, d080506zb@gmail.com, echris.zhang@usask.ca
Keywords: Droplets generation, modeling and simulation, T-junction, CFD
Abstract.
The capillary number of the cross-flow turns out to be the key factors in the droplet generation process.
Song [1] found that use of different types of fluids for the flows can affect the droplet generation.
From their work, the capillary number and the relative flow rates of the continuous and dispersed flow were found to be two important factors for drolet generation.
The properties of the fluids.
The capillary number of the cross-flow turns out to be the key factors in the droplet generation process.
Song [1] found that use of different types of fluids for the flows can affect the droplet generation.
From their work, the capillary number and the relative flow rates of the continuous and dispersed flow were found to be two important factors for drolet generation.
The properties of the fluids.
Online since: May 2014
Authors: Can Zhang, Jian Rong Cai, Yu Qing Duan, Liang Xu
First, the porogen should produce large pores to assure good flow-through properties of the resultant MIP.
As shown in Fig.3, with the increase of γ-MAPS, the pore size became smaller and the flow-through property diminished slowly, which could further affect the selectivity of the capillary monolithic column.
For MIP monolith column, the separation factors (α = kcarbaryl/kanalogs) were kcarbaryl/kfenobucarb 5.96 and kcarbaryl/kmetolcarb 4.62, respectively.
The RSD values of the separation factors were smaller than 5.1%.
The RSD values of the migration times and separation factors were not higher than 4.5% and 10.3%, respectively.
As shown in Fig.3, with the increase of γ-MAPS, the pore size became smaller and the flow-through property diminished slowly, which could further affect the selectivity of the capillary monolithic column.
For MIP monolith column, the separation factors (α = kcarbaryl/kanalogs) were kcarbaryl/kfenobucarb 5.96 and kcarbaryl/kmetolcarb 4.62, respectively.
The RSD values of the separation factors were smaller than 5.1%.
The RSD values of the migration times and separation factors were not higher than 4.5% and 10.3%, respectively.
Online since: November 2020
Authors: Jiří Švejcar, Karel Slámečka, Lenka Klakurková, Ladislav Čelko, Petr Skalka, David Jech, Jozef Kaiser, Ivana Ročňáková, Daniel Holemý
The Influence of Surface Dipping and Bulk Filling Agents on Properties of High-Speed Grinding Wheels: Materialographic-Based Numerical Modelling
Ladislav Čelko1,a*, Petr Skalka1,b, Karel Slámečka1,c, David Jech1,d,
Lenka Klakurková1,e, Ivana Ročňáková1,f, Jiří Švejcar1,g,
Daniel Holemý2,h and Jozef Kaiser1,i
1Research Group of Materials Characterization and Advanced Coatings, Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
2Best - Business, a. s., Zbraslavecká 777, 679 72 Kunštát, Czech Republic
aladislav.celko@ceitec.vutbr.cz, bpetr.skalka@ceitec.vutbr.cz, ckarel.slamecka@ceitec.vutbr.cz, ddavid.jech@ceitec.vutbr.cz, elenka.klakurkova@ceitec.vutbr.cz, fivana.rocnakova@ceitec.vutbr.cz, gjiri.svejcar@ceitec.vutbr.cz, hdaniel.holemy@bestb.cz, ijosef.kaiser@ceitec.vutbr.cz
Keywords: Grinding tools, Structure, Scanning electron microscopy, FE Analysis, Surface dipping, Bulk filling.
Furthermore, porosity is one of the most important factors influencing the performance of the grinding wheel [3].
Besides cooling and removal of the chips and abrasive generated during the grinding process, porosity, together with volumetric composition of the wheel affect mechanical properties and thus determine operational constraints.
The properties of present material components were assumed to be as follows: the Young’s modulus E = 1150 GPa and Poisson’s ratio n = 0.15 for abrasive grains, and E = 300 GPa and n = 0.27 for the binder.
Furthermore, porosity is one of the most important factors influencing the performance of the grinding wheel [3].
Besides cooling and removal of the chips and abrasive generated during the grinding process, porosity, together with volumetric composition of the wheel affect mechanical properties and thus determine operational constraints.
The properties of present material components were assumed to be as follows: the Young’s modulus E = 1150 GPa and Poisson’s ratio n = 0.15 for abrasive grains, and E = 300 GPa and n = 0.27 for the binder.
Online since: January 2021
Authors: Vu Ngoc Pi, Nguyen Hong Linh, Bui Thanh Danh, Nguyen Van Cuong, Nguyen Manh Cuong, Le Hong Ky, Tran Thi Hong, Le Thu Quy, Do Thi Tam
Input factors
No.
In the mentioned method, the signal-to-noise ratio (S/N) is used to justify the influence of process factors.
Optimization of machining time The results of analyzing the impact of the input factors on S/N of the machining time are defined in Table 6, 7 and Fig. 3.
From the ANOVA results of the average machining time values (Table 5), it is noted that IP is the most important factor that affected the machining time.
Calculated and experimental results Objective properties Optimal process parameters Calculation Experiment Error (%) Ton2/Cp3/Toff1/IP3/SV1 Ton2/Cp3/Toff1/IP3/SV1 Machining time (s) 2849 2568 9.86 To evaluate the proposed model, an experiment was done with the optimum input factors and Table 8 shows the experimental and calculated results.
In the mentioned method, the signal-to-noise ratio (S/N) is used to justify the influence of process factors.
Optimization of machining time The results of analyzing the impact of the input factors on S/N of the machining time are defined in Table 6, 7 and Fig. 3.
From the ANOVA results of the average machining time values (Table 5), it is noted that IP is the most important factor that affected the machining time.
Calculated and experimental results Objective properties Optimal process parameters Calculation Experiment Error (%) Ton2/Cp3/Toff1/IP3/SV1 Ton2/Cp3/Toff1/IP3/SV1 Machining time (s) 2849 2568 9.86 To evaluate the proposed model, an experiment was done with the optimum input factors and Table 8 shows the experimental and calculated results.
Online since: November 2012
Authors: Pei Qi Ge, Jing Liang Jiang, Ying Zhang, De Xiang Wang
A Mathematical Model of Single Grain Forces in Grinding Process
Jiang Jingliang1,a, Ge Peiqi1,b, Zhang Ying1,c, Wang Dexiang1
1School of Mechanical Engineering, Shandong University, Jinan 250061
acba1981@126.com, bpqge@sdu.edu.cn, cgirlcheryl@163.com
Keywords: Grinding, Single grain forces, mathematical model.
Substituting the physical and mechanical properties of workpiece material (for example, choosing a common used bearing steel, GCr15): σs=785MPa, E2=207GPa, ν2=0.3 into Eq.1 and get: (2) Eq.2 shows that the value of the penetration depth of a grain will be very small when the workpiece material is in elastic deformation stage.
In Eq.3 and Eq.8, the single grain force models are mainly related with physical and mechanical properties of workpiece materials such as hardness, shear yield strength, friction coefficient with grain and so on.
The grain penetration depth is affected by grinding parameters and the value is in the range of 2~20μm as usual.
This model of single abrasive grain forces take grinding parameters, properties of grinding wheel and workpiece in to considered and can be directly used in total grinding force calculation.
Substituting the physical and mechanical properties of workpiece material (for example, choosing a common used bearing steel, GCr15): σs=785MPa, E2=207GPa, ν2=0.3 into Eq.1 and get: (2) Eq.2 shows that the value of the penetration depth of a grain will be very small when the workpiece material is in elastic deformation stage.
In Eq.3 and Eq.8, the single grain force models are mainly related with physical and mechanical properties of workpiece materials such as hardness, shear yield strength, friction coefficient with grain and so on.
The grain penetration depth is affected by grinding parameters and the value is in the range of 2~20μm as usual.
This model of single abrasive grain forces take grinding parameters, properties of grinding wheel and workpiece in to considered and can be directly used in total grinding force calculation.
Online since: August 2014
Authors: Sergei Petinov
This version of the approach allows assessment of fatigue properties of the detail without utilizing Neuber’s formula and presenting the loading history in the block-type format.
In the high-stress range of the service loading the input of this over-estimation of fatigue damage in the total sum typically is insignificant due to stochastic properties of excitation.
(2) Criterion (Eq. 2), as well as (Eq. 1), provides conservative evaluation of fatigue properties of a structure, since it underestimates the fatigue lives approximately, in the range of cycles, as indicated Manson in discussion of [3].
The stress in the flange at the cut ending is magnified by the cut shape; respective stress concentration factors must be calculated by the finite-element method.
Peterson, Stress Concentration Factors, A Handbook, J.Wiley & Sons, Hoboken, NJ, USA (1989)
In the high-stress range of the service loading the input of this over-estimation of fatigue damage in the total sum typically is insignificant due to stochastic properties of excitation.
(2) Criterion (Eq. 2), as well as (Eq. 1), provides conservative evaluation of fatigue properties of a structure, since it underestimates the fatigue lives approximately, in the range of cycles, as indicated Manson in discussion of [3].
The stress in the flange at the cut ending is magnified by the cut shape; respective stress concentration factors must be calculated by the finite-element method.
Peterson, Stress Concentration Factors, A Handbook, J.Wiley & Sons, Hoboken, NJ, USA (1989)
Online since: July 2016
Authors: Hong Guan, Benoit P. Gilbert, Nima Talebian, Nadia Baldassino
Rao et al [12] and Sajja et al [4] investigated the factors affecting the shear stiffness of steel storage rack upright frames.
These factors include the upright size, the aspect ratio of frame panels (height/width), the eccentricity of bracing members, the bracing configuration and bolt bending.
The cross-sectional properties of the upright and bracing members are presented in Table 1.
The model will then be used to quantify the contribution of all factors influencing the transverse shear stiffness of bolted cold-formed steel upright frames.
The model will be further verified and used to quantify the contribution of all factors influencing the transverse shear stiffness of the upright frames.
These factors include the upright size, the aspect ratio of frame panels (height/width), the eccentricity of bracing members, the bracing configuration and bolt bending.
The cross-sectional properties of the upright and bracing members are presented in Table 1.
The model will then be used to quantify the contribution of all factors influencing the transverse shear stiffness of bolted cold-formed steel upright frames.
The model will be further verified and used to quantify the contribution of all factors influencing the transverse shear stiffness of the upright frames.
Online since: December 2003
Authors: Soo Ryong Kim, In Soo Hwang, Sang Hwan Cho, Kyung Sik Oh, Yong Chae Chung, Jong Kyu Lee
In this work, properties of tricalcium phosphate (TCP)-tetracalcium phosphate
(TTCP)-dicalcium phosphate dehydrate (DCPD) bone cement containing dense TCP granules were
studied. 5 groups of cement were prepared with respect to the blending ratio between granular and
powdery TCP.
However, the mechanical properties need to be improved.
It is well known that the particle size and the activity of the starting materials are critical parameter influencing the mechanical properties (setting time and compressive strength) of hydraulic cements [1].
Addition of granules in calcium phosphate cement affects on powder to liquid ratio (P/L).
The study has shown the two important factors in synthesizing self-setting cements with superior strength when introducing TCP granules.
However, the mechanical properties need to be improved.
It is well known that the particle size and the activity of the starting materials are critical parameter influencing the mechanical properties (setting time and compressive strength) of hydraulic cements [1].
Addition of granules in calcium phosphate cement affects on powder to liquid ratio (P/L).
The study has shown the two important factors in synthesizing self-setting cements with superior strength when introducing TCP granules.
Online since: April 2003
Authors: Y. Kuen, Y. Gao, Z. Tao, S. Tse
Tao
Department of Mechanical Engineering, Hong Kong University of Science and Technology
Clear Water Bay, Kowloon, Hong Kong, China
Keywords: Machining, In-process Measurement, Coolant Flow Patterns
Abstract.
It was found that the coolant flow patterns were one of the critical factors, which affect the effectiveness of the measurement.
However, the opaque optical property of the coolants can be a problem for the in-process measurement of surface profiles using optical instruments.
Based on the properties of the original images obtained from the experiment, it was found that all the pixels for the peak of the histogram are the background and all the pixels for the lowest point are the flow pattern.
The location of the pattern and the area under the curve are the important factors which affect the effectiveness of the measurement by the laser sensor.
It was found that the coolant flow patterns were one of the critical factors, which affect the effectiveness of the measurement.
However, the opaque optical property of the coolants can be a problem for the in-process measurement of surface profiles using optical instruments.
Based on the properties of the original images obtained from the experiment, it was found that all the pixels for the peak of the histogram are the background and all the pixels for the lowest point are the flow pattern.
The location of the pattern and the area under the curve are the important factors which affect the effectiveness of the measurement by the laser sensor.