Influences of uniaxial stress and moisture content on the thermal conductivity of rocks

Görgülü, Kazım; Durutürk, Y. Selim; Demirci, Ahmet; Poyraz, Bayram

doi:10.1016/j.ijrmms.2008.02.004

Cited by 32 publications

(9 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Water with 0.6 W/m·K of thermal conductivity at room temperature is an important factor to affect heat flow in porous rocks. 22 , 24 It could replace some air that is 0.03 W/m·K at room temperature in pores and improve the thermal conductivity of samples. Therefore, the thermal conductivity of each coal with adsorbed water is improved, while their rank is not changed.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Relationship between Thermal Conductivity and Chemical Structures of Chinese Coals

2020

View full text Add to dashboard Cite

Three different ranks of Chinese coals were investigated on the thermal conductivity and corresponding molecular structure by thermal analyzer, 13 C NMR, and HRTEM techniques. The thermal conductivity of coals measured in room temperature first shows a decrease, then a slight increase, and finally a sharp increase with increasing coalification. Ranging from 30 to 150 °C, increasing the temperature slightly improves the thermal conductivity of coals with varying degrees. Water with a higher thermal conductivity than air contributes to the thermal conductivity of porous coal samples. The value of thermal conductivity is higher along coal bedding planes than when perpendicular to beddings, which indicates the anisotropy of coal thermal conductivity. The anisotropy degree increases with the rank of coals and is affected by clay minerals when coals adsorb water. Molecular structure analysis shows that polycondensed aromatic ring related to lattice vibration contributes to the increase of thermal conductivity. The aliphatic bridges among aromatic clusters ensure the continuity of atom vibrations and contribute to energy transport, but the free-ended side chains have the opposite effect. The relative ordered distributions of lattice fringes of anthracite, which were higher than those of bituminous coal, enhance the anisotropy of thermal conductivity.

show abstract

Section: Resultsmentioning

confidence: 99%

“… 17 , 18 By contrast, sandstones and granite are relatively isotropic and easily influenced by moisture, porosity, and pressure in thermal conductivity. 19 − 21 Their thermal conductivities increase with increasing pressure and moisture content 22 , 23 and with decreasing porosity. 24 …”

Section: Introductionmentioning

confidence: 99%

Relationship between Thermal Conductivity and Chemical Structures of Chinese Coals

2020

View full text Add to dashboard Cite

show abstract

“…These areas require more accurate thermal conductivity. The thermal conductivity of rock is affected by many factors, including mineral composition, porosity [4][5][6][7][8][9], water content [10][11][12][13][14], temperature and pressure [15][16][17][18][19], etc. Many scholars have obtained models with different thermal conductivity of rocks by considering different influencing factors.…”

Section: Introductionmentioning

confidence: 99%

Mineral Composition Impact on the Thermal Conductivity of Granites Based on Geothermal Field Experiments in the Songliao and Gonghe Basins, China

Zhang

et al. 2022

Minerals

View full text Add to dashboard Cite

Accurate estimation of thermal conductivity of rocks is of paramount importance for projects such as the development of hot dry rock and the geological storage of nuclear waste. In this paper, 30 granite samples from the Songliao and Gonghe Basins in China were tested by X-ray diffraction, polarizing microscope, and Thermal Conductivity Scanning (TCS) measurements. Different mineral contents determine the thermal conductivity of the rock as a whole. The geometric average model and the harmonic average model have great limitations. Combined with the above two models, a new model is proposed for estimating the thermal conductivity, and results are less different from the measured values and have universal applicability. The relative estimation error on the thermal conductivity calculated by mineral composition is significantly reduced. The accuracy of thermal conductivity calculation can be improved by mineral composition.

show abstract

“…During the preceding four decades, various rock constitutive models have been established from theoretical, experimental approaches (e.g., [11][12][13][14][15]). Based on the traditional continuum mechanics and damage theory, thermoplastic and thermoelastic brittle models were proposed [16,17].…”

Section: Introductionmentioning

confidence: 99%

A Statistical Constitutive Model considering Deterioration for Brittle Rocks under a Coupled Thermal-Mechanical Condition

Gao

Wei

et al. 2018

Geofluids

View full text Add to dashboard Cite

Due to active actions of groundwater and geothermal, the stability of underground engineering is important during geological structure active area. The damage mechanical theory and statistical mesoscopic strength theory based on Weibull distribution are widely used to discuss constitutive behaviors of rocks. In these theories, a statistical method is used to capture mesoscopic properties of rocks in order to generate a realistic behavior at a macroscopic scale. Based on the above theories, this paper aims at establishing a constitutive relation of brittle rocks under thermal-mechanical coupling conditions. First, a statistical damage constitutive model was established by considering the thermal effects and crack initiation strength. Subsequently, the parameters of the model were determined and expressed according to the characteristics of stress-strain curve. Third, the model was verified by conventional triaxial experiments under thermal-mechanical actions, and the experimental data and theoretical results were compared and analyzed in the case study. Finally, the physical meaning of the parameters and their effects on the model performance were discussed.

show abstract

Influences of uniaxial stress and moisture content on the thermal conductivity of rocks

Cited by 32 publications

References 10 publications

Relationship between Thermal Conductivity and Chemical Structures of Chinese Coals

Relationship between Thermal Conductivity and Chemical Structures of Chinese Coals

Mineral Composition Impact on the Thermal Conductivity of Granites Based on Geothermal Field Experiments in the Songliao and Gonghe Basins, China

A Statistical Constitutive Model considering Deterioration for Brittle Rocks under a Coupled Thermal-Mechanical Condition

Contact Info

Product

Resources

About