Increase of Bearing Loads Due to Large Normal Stress Differences in Viscoelastic Lubricants

1969 ◽  
Vol 36 (3) ◽  
pp. 634-635 ◽  
Author(s):  
R. I. Tanner
Keyword(s):  
Bearing Capacity ◽  
Normal Stress ◽  
Second Order ◽  
Stress Effects ◽  
Slider Bearings ◽  
Normal Stress Differences ◽  
Bearing Loads

The calculation of increased bearing capacity due to large viscoelastic or normal stress effects is carried out exactly for plane slider bearings with a second-order fluid lubricant.

scholarly journals Normal Stress Effects in the Creep of Ice

1985 ◽  
Vol 31 (108) ◽  
pp. 120-126 ◽  
Author(s):  
David F. McTigue ◽  
Stephen L. Passman ◽  
Stephen J. Jones
Keyword(s):  
Normal Stress ◽  
Principal Stress ◽  
Exact Analytical Solution ◽  
Secondary Creep ◽  
Normal Stresses ◽  
Stress Effects ◽  
Polycrystalline Ice ◽  
Biaxial Creep ◽  
Normal Stress Differences ◽  
Steep Slopes

AbstractMost non-linear fluids for which the appropriate measurements have been made exhibit non-zero and unequal normal stress differences in shearing flows. Power-law models such as Glen’s law cannot represent this phenomenon. The simplest constitutive equation that does embody normal stress effects defines the second-order fluid. An exact analytical solution for biaxial creep of such a fluid is fit to data from four tests on polycrystalline ice. The model gives an excellent representation of both primary and secondary creep. The fits provide values for the three material constants. These coefficients indicate positive first and second normal stress differences. One consequence is the prediction that a steady open-channel flow will exhibit a longitudinal free-surface depression of up to several meters for sufficiently thick ice on steep slopes. In addition, the compressive principal stress at the channel margin is decreased and the tensile principal stress is increased in magnitude over those predicted by models without normal stresses. The normal stresses thus favor the formation of crevasses. Furthermore, the angle these crevasses form with the channel margin is decreased.

scholarly journals On the Significance of Normal Stress Effects in the Flow of Glaciers

1987 ◽  
Vol 33 (115) ◽  
pp. 268-273 ◽  
Author(s):  
Chi-Sing Man ◽  
Quan-Xin Sun
Keyword(s):  
Normal Stress ◽  
Creep Behaviour ◽  
Laboratory Data ◽  
Constitutive Models ◽  
Second Order ◽  
Material Parameters ◽  
Stress Effects ◽  
Polycrystalline Ice ◽  
Glacier Ice ◽  
Flow Law

AbstractMcTigue and others (1985) identified a possible problem in the type of constitutive equation usually used for modeling the creep behaviour of polycrystalline ice. They pointed out that Glen’s flow law necessarily excludes the consideration of normal stress effects, which are of great significance in other disciplines that consider non-Newtonian fluids. Using the second-order fluid (with material parameters evaluated from laboratory data) as a tentative model for ice, they reached the conclusion that normal stress effects may be discernible in natural glacier flow. But, as noted by McTigue and others, the second-order fluid “fails to represent the non-linear rate dependence of ice in shear”; therefore it is in fact not a suitable constitutive model for glacier ice in shearing flow. In this note, parallel to what McTigue and others did for the second-order fluid, we present a similar analysis for (I) the modified second-order fluid and (II) the power-law fluid of grade 2, both of which are constitutive models recently proposed by Man as a tentative generalization of Glen’s flow law. Both models (I) and (II) can represent normal stress effects, and both agree with Glen’s flow law in the prediction of the depth profile of velocity in the steady laminar flow of glaciers. For ease of comparison, the same creep data of McTigue and others are used in quantifying the material parameters in these two models. Both models (I) and (II) predict far less pronounced normal stress effects in glaciers than those estimated by McTigue and others (whose data analysis in fact suffered from inconsistencies and over-parameterization).

Normal Stress Effects in Second‐Order Fluids

1964 ◽  
Vol 35 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Bernard D. Coleman ◽  
Hershel Markovitz
Keyword(s):  
Normal Stress ◽  
Second Order ◽  
Stress Effects ◽  
Second Order Fluids

scholarly journals Normal Stress Effects in the Creep of Ice

1985 ◽  
Vol 31 (108) ◽  
pp. 120-126 ◽  
Author(s):  
David F. McTigue ◽  
Stephen L. Passman ◽  
Stephen J. Jones
Keyword(s):  
Normal Stress ◽  
Principal Stress ◽  
Exact Analytical Solution ◽  
Secondary Creep ◽  
Normal Stresses ◽  
Stress Effects ◽  
Polycrystalline Ice ◽  
Biaxial Creep ◽  
Normal Stress Differences ◽  
Steep Slopes

AbstractMost non-linear fluids for which the appropriate measurements have been made exhibit non-zero and unequal normal stress differences in shearing flows. Power-law models such as Glen’s law cannot represent this phenomenon. The simplest constitutive equation that does embody normal stress effects defines the second-order fluid. An exact analytical solution for biaxial creep of such a fluid is fit to data from four tests on polycrystalline ice. The model gives an excellent representation of both primary and secondary creep. The fits provide values for the three material constants. These coefficients indicate positive first and second normal stress differences. One consequence is the prediction that a steady open-channel flow will exhibit a longitudinal free-surface depression of up to several meters for sufficiently thick ice on steep slopes. In addition, the compressive principal stress at the channel margin is decreased and the tensile principal stress is increased in magnitude over those predicted by models without normal stresses. The normal stresses thus favor the formation of crevasses. Furthermore, the angle these crevasses form with the channel margin is decreased.

scholarly journals On the Significance of Normal Stress Effects in the Flow of Glaciers

1987 ◽  
Vol 33 (115) ◽  
pp. 268-273 ◽  
Author(s):  
Chi-Sing Man ◽  
Quan-Xin Sun
Keyword(s):  
Normal Stress ◽  
Creep Behaviour ◽  
Laboratory Data ◽  
Constitutive Models ◽  
Second Order ◽  
Material Parameters ◽  
Stress Effects ◽  
Polycrystalline Ice ◽  
Glacier Ice ◽  
Flow Law

AbstractMcTigue and others (1985) identified a possible problem in the type of constitutive equation usually used for modeling the creep behaviour of polycrystalline ice. They pointed out that Glen’s flow law necessarily excludes the consideration of normal stress effects, which are of great significance in other disciplines that consider non-Newtonian fluids. Using the second-order fluid (with material parameters evaluated from laboratory data) as a tentative model for ice, they reached the conclusion that normal stress effects may be discernible in natural glacier flow. But, as noted by McTigue and others, the second-order fluid “fails to represent the non-linear rate dependence of ice in shear”; therefore it is in fact not a suitable constitutive model for glacier ice in shearing flow. In this note, parallel to what McTigue and others did for the second-order fluid, we present a similar analysis for (I) the modified second-order fluid and (II) the power-law fluid of grade 2, both of which are constitutive models recently proposed by Man as a tentative generalization of Glen’s flow law. Both models (I) and (II) can represent normal stress effects, and both agree with Glen’s flow law in the prediction of the depth profile of velocity in the steady laminar flow of glaciers. For ease of comparison, the same creep data of McTigue and others are used in quantifying the material parameters in these two models. Both models (I) and (II) predict far less pronounced normal stress effects in glaciers than those estimated by McTigue and others (whose data analysis in fact suffered from inconsistencies and over-parameterization).

Out-of-plane static compression and energy absorption of paper hierarchical corrugation sandwich panels

2021 ◽  
pp. 030932472110085
Author(s):  
Huineng Wang ◽  
Yanfeng Guo ◽  
Yungang Fu ◽  
Dan Li
Keyword(s):  
Yield Strength ◽  
Bearing Capacity ◽  
Energy Absorption ◽  
Sandwich Panel ◽  
Second Order ◽  
Compression Rate ◽  
Static Compression ◽  
First Order ◽  
Out Of Plane ◽  
Analytical Approaches

This study introduces the opinion of the corrugation hierarchy to develop the second-order corrugation paperboard, and explore the deformation characteristics, yield strength, and energy absorbing capacity under out-of-plane static evenly compression loading by experimental and analytical approaches. On the basis of the inclined-straight strut elements of corrugation unit and plastic hinge lines, the yield and crushing strengths of corrugation unit were analyzed. This study shows that as the compressive stress increases, the second-order corrugation core layer is firstly crushed, and the first-order corrugation structures gradually compacted until the failure of entire structure. The corrugation type has an obvious influence on the yield strength of the corrugation sandwich panel, and the yield strength of B-flute corrugation sandwich panel is wholly higher than that of the C-flute structure. At the same compression rate, the flute type has a significant impact on energy absorption, and the C-flute second-order corrugation sandwich panel has better bearing capacity than the B-flute structure. The second-order corrugation sandwich panel has a better bearing capacity than the first-order structure. The static compression rate has little effect on the yield strength and deformation mode. However, with the increase of the static compression rate, the corrugation sandwich panel has a better cushioning energy absorption and material utilization rate.

Investigation of stresses and normal stress differences behavior on symmetric and asymmetric polymeric fluid flow through planar gradual expansions

Meccanica ◽  
2016 ◽  
Vol 52 (8) ◽  
pp. 1889-1909 ◽  
Author(s):  
M. Norouzi ◽  
A. Shahbani Zahiri ◽  
M. M. Shahmardan ◽  
H. Hassanzadeh ◽  
M. Davoodi
Keyword(s):  
Fluid Flow ◽  
Normal Stress ◽  
Polymeric Fluid ◽  
Flow Through ◽  
Normal Stress Differences

Method of normal stress differences in photoelasticity

1982 ◽  
Vol 18 (8) ◽  
pp. 763-766
Author(s):  
Yu. I. Vologzhaninov ◽  
S. G. Demidenko ◽  
A. V. Churpita
Keyword(s):  
Normal Stress ◽  
Normal Stress Differences

Normal stress effects on Knudsen flow

2018 ◽  
Vol 30 (1) ◽  
pp. 013103
Author(s):  
Byung Chan Eu
Keyword(s):  
Normal Stress ◽  
Knudsen Flow ◽  
Stress Effects
Sign in / Sign up

Export Citation Format

Share Document