scholarly journals A Random Pore Model of sea ice for predicting its mechanical properties

Author(s):  
Z. Zong
1994 ◽  
Vol 19 ◽  
pp. 39-48 ◽  
Author(s):  
Gary A. Kuehn ◽  
Erland M. Schulson

Understanding the mechanical properties of saline ice is important for engineering design as well as for operations in polar regions. In order to gain understanding of the basic mechanisms of deformation and fracture, laboratory-grown columnar saline ice, representative of first-year sea ice, was tested in uniaxial compression under a variety of conditions of Strain rate (10−7to 10−1s−1), temper-aiure (−40°, −20°, −10° and −5°C) and orientation (loading vertically or horizontally: i.e. parallel or perpendicular to the growth direction). The range of strain rate spanned the ductile-to-brittle transition for every combination of temperature and specimen orientation. The results of over 250 tests are reported. Mechanical properties, failure mode and ice structure are analyzed with respect to the testing conditons. The results show that strength is dependent upon the ice structure, orientation, strain rate and temperature. During loading in the ductile regime the structure is altered (e.g. by recrystallization), whereas in the brittle regime the majority of the structural change is through cracking. The results are compared to results from the literature on both natural sea ice and laboratory-grown saline ice. Where possible, they are interpreted in terms of micromechanica] models.


2016 ◽  
Vol 18 (1) ◽  
pp. 93-98 ◽  
Author(s):  
S.M.M. Nouri ◽  
H. Ale Ebrahim

Abstract In this work, a modified random pore model was developed to study the kinetics of the carbonation reaction of CaO. Pore size distributions of the CaO pellets were measured by nitrogen adsorption and mercury porosimetry methods. The experiments were carried out in a thermogravimeter at different isothermal temperatures and CO2 partial pressures. A fractional concentration dependency function showed the best accuracy for predicting the intrinsic rate of reaction. The activation energy was determined as 11 kcal/mole between 550–700°C. The effect of product layer formation was also taken into account by using the variable product layer diffusivity. Also, the model was successfully predicted the natural lime carbonation reaction data extracted from the literature.


2013 ◽  
Vol 647 ◽  
pp. 683-687
Author(s):  
Mi Gong ◽  
Hong Chao Kou ◽  
Yu Song Yang ◽  
Guang Sheng Xu ◽  
Jin Shan Li ◽  
...  

The pore structures on mechanical properties of porous Ti were investigated by 3D finite element models. Calculated elastic modulus and yield strength suggested that square-pore models exhibit lower modulus and higher strength compared with another two kinds of shapes (circle and hexagonal). In addition, under the condition of medium porosity (58.96%), integrated property was found in square-pore model which elastic modulus was 26.97GPa, less than 1/3 of hexagonal-pore model; while the yield strength maintained 63.82MPa, doubled the figure of circle-pore model. Thus, models with square-pore structures show potential perspective as hard tissue replacements. Investigation on anisotropy of microstructure implies that the elastic modulus was affected more intensively than the yield strength.


2014 ◽  
Vol 37 (12) ◽  
pp. 2037-2046 ◽  
Author(s):  
Hadi Moshiri ◽  
Bahram Nasernejad ◽  
Habib Ale Ebrahim ◽  
Mahboobeh Taheri

AIChE Journal ◽  
1981 ◽  
Vol 27 (2) ◽  
pp. 247-254 ◽  
Author(s):  
S. K. Bhatia ◽  
D. D. Perlmutter

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