Identification of the Thermal Conductivity Coefficient of a Substance from a Temperature Field in a Three-Dimensional Domain

Temperature is an important factor in designing and maintaining tunnels, especially in cold regions. We present three-dimensional numerical simulations of tunnel temperature fields at different temperature conditions. We study the tunnel temperature field in two different conditions with relatively low and high ambient temperatures representing winter and summer of northeast China. We specifically study how these temperature conditions affect tunnel temperature and its migration to surrounding rocks. We show how placing an insulation layer could affect the temperature distribution within and around tunnels. Our results show that the temperature field without using an insulation layer is closer to the air temperature in the tunnel, and that the insulation layer has shielding effects and could plays an important role in preventing temperature migration to surrounding rocks. We further analyzed how thermal conductivity and thickness of insulation layer control the temperature distribution. The thermal conductivity and thickness of insulation layer only affect the temperature of the surrounding rocks which are located at distances below ~20 m from the lining.

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Research on Temperature Field about Cutting Area in Plunge Milling Ti Alloy Based on Finite Element

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.102-104.630 ◽

2010 ◽

Vol 102-104 ◽

pp. 630-633

Author(s):

Xu Da Qin ◽

Wei Cheng Liu ◽

Hao Jia ◽

Xiao Lai Ji

Keyword(s):

Thermal Conductivity ◽

Finite Element ◽

Temperature Field ◽

Thermal Conductivity Coefficient ◽

Cutting Speed ◽

Cutting Parameters ◽

Ti Alloy ◽

Plunge Milling ◽

Finite Element Software

Because of the small thermal conductivity coefficient of Ti alloy, the heat cannot disperse timely and accumulate seriously when plunge milling Ti alloy. If the cutting parameters can not be controlled well, the phenomenon of sticking will happen easily. According to the simulation and analysis of temperature field by using finite element software ABAQUS, the influence on cutting speed and feed for the Distributing of Temperature Field about Cutting Area in Plunge Milling Ti Alloy is acquired.

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Effect of Soil Moisture on Soil Temperature Field Near Buried Pipe

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.650 ◽

2012 ◽

Vol 204-208 ◽

pp. 650-653

Author(s):

Jiang Li ◽

Jun Ping Fu ◽

Wu Gang Xie

Keyword(s):

Thermal Conductivity ◽

Temperature Field ◽

Soil Moisture ◽

Heat Exchanger ◽

Moisture Content ◽

Field Experiment ◽

Soil Temperature ◽

Soil Moisture Content ◽

Thermal Conductivity Coefficient ◽

Soil Thermal Conductivity

System effectiveness and useful life of heat pump are directly affected by whether the design of ground heat exchanger is reasonable or not. The efficiency of heat exchanger has a close relationship with soil thermal conductivity coefficient and heat diffusivity, while soil moisture content affects soil thermal conductivity coefficient and soil temperature field. In this paper, we perform numerical simulation on CFD software. Then we study the soil temperature changes through field experiment in different soil moisture content on field experiment and finally obtained the relationships of the moisture content with the single U ground soil temperature field.

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Analysis of the Sintered Porous Brick Wall Insulation Performance Using Different Ways Masonry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1092-1093.550 ◽

2015 ◽

Vol 1092-1093 ◽

pp. 550-554

Author(s):

Jian Long Liu ◽

Jie Nan Xie ◽

Peng Liu ◽

Mu Ye Huang

Keyword(s):

Thermal Conductivity ◽

Void Ratio ◽

Thermal Conductivity Coefficient ◽

Three Dimensional ◽

Masonry Wall ◽

Brick Wall ◽

Equivalent Thermal Conductivity ◽

Insulation Effect ◽

Heat Transfers ◽

Insulation Performance

Through the three-dimensional heat transfers numerical simulation of eight kinds with the different number of holes, void ratio and arrangement of sintered shale porous brick (size: 240mm×190mm×90mm), which simulate the sintered porous brick under two different laying way that is 240mm wall and 190mm wall of equivalent thermal conductivity. The result shows: the same kind of porous brick as 240mm wall and 190mm wall, when the equivalent thermal conductivity coefficient has phased difference that the wall insulation effect is obviously different. Through the analysis of two different methods of the masonry wall thermal insulation performance of the influence by different reasons, targeted to put forward some suggestions in order to improve calorific performance of the wall.

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The Evaluation of the Simulation of Thermal Conductivity Coefficient Based on the Concrete with Minimum Thermal Resistance

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.3320 ◽

2013 ◽

Vol 448-453 ◽

pp. 3320-3323

Author(s):

Chao Zhao ◽

Du Shun Ting

Keyword(s):

Thermal Conductivity ◽

Temperature Field ◽

Thermal Resistance ◽

Thermal Performance ◽

Theoretical Basis ◽

Thermal Conductivity Coefficient ◽

Great Influence ◽

Coefficient Of Thermal Conductivity ◽

Primary Materials

The coefficient of thermal conductivity is one of the important parameters of concretes thermal performance and it has a relatively great influence on the temperature field inside its structure. This paper explores the basic equipments of the experiment on concretes coefficient of thermal conductivity and the requirements on configuration of primary materials. In the meanwhile, it studies the establishment of the model of concretes coefficient of thermal conductivity from the theoretical basis of thermal conductivity simulation, the division of thermal fluxs pathways and that of K in the formula of the coefficient of thermal conductivity.

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