A Study on Elastic Stress Waves Generated during Cutting Process using Simulation Analysis

Elastic stress wave theory is developed and the stress waves in the impacted plate are examined in the paper. Generalized linear elasticity is adopted where the couple stress and curvature tensor are both deviatoric tensors and they meet a linear constitutive relation. It is found that there exist volumetric, rotational, and deviatoric waves in the generalized elastic solids. However, for macro-scale elastic solids only two wave modes, namely a volumetric wave and a deviatoric wave should be taken into account. Wave motion in plate impact tests is studied that a volumetric wave and a deviatoric wave are proposed. A set of exact solutions is attained for elastic stress waves in an impact plate. Excitation of stress waves at impact surface and reflection at free surface are formulated. Propagation of stress waves in the plate is analyzed in the waveforms. The predicted stress history in a ceramic plate under impact is agreed very well with the experiment measurement.

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Numerical Simulation Analysis of the Effect on the One-Dimension Assumption in Different Diameter SHPB Pressure Bar by Two Kinds of Loading Waveform

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.787.759 ◽

2013 ◽

Vol 787 ◽

pp. 759-764

Author(s):

Sheng Zhang ◽

Xiang Hao Yang ◽

Xin Wen Li

Keyword(s):

Stress Wave ◽

Split Hopkinson Pressure Bar ◽

Simulation Analysis ◽

Sine Wave ◽

Stress Waves ◽

One Dimension ◽

Hopkinson Pressure Bar ◽

Finite Element Software ◽

The One ◽

Pressure Bar

t is one of precondition of determining rock material dynamic parameters for one-dimension assumption of the elastic pressure bar. In order to analyze its effect by loading wave type, the dynamic stress was simulated with Ls-dynamic finite element software, when SHPB(Split Hopkinson Pressure Bar) pressure bar with diameter of 50 mm, 75 mm and 100 mm were impacted respectively by a cycle rectangular loading wave and half sine loading wave. The stress waves of cross section in different diameter pressure bar and the different distance with pressure bar end were compared and analyzed. The results indicated that the dispersion of stress waves was very serious and the matching ability of stress wave at different distances in pressure bar was poor when the rectangular wave was loaded. However, the dispersion of stress wave was not obvious with the increase of the diameter of pressure bar and the change of pressure bar when the half sine wave was loaded. The half sine loading wave which can strictly meet the one-dimension assumption is one of the ideal loading waveforms of the rocky heterogeneous materials.

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Simulation Analysis of Cutting Resistance for Cutting Tools with Different Rakes in the Strike Working Condition

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.364.465 ◽

2013 ◽

Vol 364 ◽

pp. 465-469

Author(s):

Jian Li Wang ◽

Dian Wang ◽

Jin Hao Liu

Keyword(s):

Cutting Tool ◽

Working Condition ◽

Simulation Analysis ◽

Cutting Tools ◽

Cutting Process ◽

Resistance Curve ◽

Wood Material ◽

Cutting Resistance ◽

Anisotropy Model ◽

Orthogonal Anisotropy

Brush-cutter would always bring cutting shock in its cutting process, and its not easy to estimate the cutting resistance by usual cutting theory and methods. The present paper emulates real cutting process by using ANSYS/LS-DYNA, and orthogonal anisotropy model was used to symbolize the wood material. The result shows that the cutting tool with a 40 degrees rake is more competent than the ones with 30 degrees and 50 degrees. This result fits common cutting theories, thus the rationality of this research is proved, and a cutting resistance curve is obtained.

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ON ELASTIC STRESS WAVES IN THE IMPACTED PLATES

Frontiers in Applied Mechanics ◽

10.1142/9781783266852_0031 ◽

2015 ◽

pp. 61-62

Author(s):

Zhanfang LIU

Keyword(s):

Elastic Stress ◽

Stress Waves

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Study on Roadheader Cutting Load at Different Properties of Coal and Rock

The Scientific World JOURNAL ◽

10.1155/2013/624512 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 6

Author(s):

Xueyi Li ◽

Binbing Huang ◽

Guoying Ma ◽

Qingliang Zeng

Keyword(s):

Simulation Analysis ◽

Cutting Process ◽

Theoretical Formula ◽

Accurate Calculation ◽

Cutting Test ◽

Cutting Head ◽

Element Simulation ◽

Geological Conditions ◽

The Relationship ◽

Selection Of

The mechanism of cutting process of roadheader with cutting head was researched, and the influences of properties of coal and rock on cutting load were deeply analyzed. Aimed at the defects of traditional calculation method of cutting load on fully expressing the complex cutting process of cutting head, the method of finite element simulation was proposed to simulate the dynamic cutting process. Aimed at the characteristics of coal and rock which affect the cutting load, several simulations with different firmness coefficient were taken repeatedly, and the relationship between three-axis force and firmness coefficient was derived. A comparative analysis of cutting pick load between simulation results and theoretical formula was carried out, and a consistency was achieved. Then cutting process with a total cutting head was carried out on this basis. The results show that the simulation analysis not only provides a reliable guarantee for the accurate calculation of the cutting head load and improves the efficiency of the cutting head cutting test but also offers a basis for selection of cutting head with different geological conditions of coal or rock.

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