scholarly journals Analysis of Heat Transfer Characteristics of Fractured Surrounding Rock in Deep Underground Spaces

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Liu Chen ◽  
Yujie Chu ◽  
Yu Zhang ◽  
Fei Han ◽  
Jie Zhang
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Temperature Field ◽  
Surrounding Rock ◽  
Fracture Aperture ◽  
Temperature Field Distribution ◽  
Average Water Temperature ◽  
Ventilation Time ◽  
Average Water ◽  
Deep Underground

The study of fluid-heat coupling in deep fractured surrounding rock is the basis of design, safety, and extraction of geothermal energy of deep underground spaces. The heat transfer and fractured media seepage theories were employed to establish a three-dimensional unsteady model for fluid-heat coupling heat transfer in fractured surrounding rock. Using COMSOL multiphysics simulation software, the temperature field of the fractured surrounding rock was determined. Furthermore, the influences of ventilation time, Darcy’s velocity, fracture aperture, and thermal conductivity coefficient of the surrounding rock on the fractured surrounding rock temperature field distribution were investigated. The results of the numerical simulation show that the ventilation time and fracture have a major impact on the temperature field distribution of the fractured surrounding rock. As ventilation time is 200 days, an average water temperature in centerline of the fracture decreases 9.4 K as Darcy’s velocity increased from 3e-4m/s to 2e-3m/s. As ventilation time is 200 days, an average water temperature in centerline of the fracture decreases 5.3 K as fracture aperture increased from 3 mm to 9 mm. A set of experimental devices for fluid-heat coupling heat transfer in surrounding rock with a single fracture was designed and built to validate the numerical simulation results. Numerical simulation results are, in general, in agreement with the experimental results.

Research on Temperature Field Distribution of Heavy Hydrostatic Thrust Bearing Rotation-Workbench at Different Rotating Velocity

2011 ◽  
Vol 239-242 ◽  
pp. 2703-2706
Author(s):  
Jun Peng Shao ◽  
Xiao Dong Yang ◽  
Yun Fei Wang ◽  
Xiao Qiu Xu ◽  
Yan Qin Zhang ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Temperature Field ◽  
Field Distribution ◽  
Thrust Bearing ◽  
State Equation ◽  
Temperature Field Distribution ◽  
Hydrostatic Bearing ◽  
Average Temperature ◽  
Heat Transfer Theory

Based on heat transfer theory, thermodynamics steady state equation of hydrostatic bearing, thermal mathematical model of hydrostatic bearing and boundary condition of numerical simulation is established. Temperature field distribution of hydrostatic bearing at different velocity is numerical simulated. Regularity of the influence of velocity on temperature field of heavy hydrostatic thrust bearing is revealed. The results show that, velocity impacted a significant influence on heat transfer and temperature field distribution of hydrostatic bearing. Average temperature of workbench steadily declined as velocity increasing, while average temperature of base gradually increased; both of them emerged serious heat concentration, but the cooling situation of workbench is better than base. The numerical simulation results could provide theoretical basis for temperature control scheme design which will improve the stability and reliability during hydrostatic bearing operation.

scholarly journals Numerical Simulation Analysis of Unsteady Temperature in Thermal Insulation Supporting Roadway

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Shuguang Zhang ◽  
Pingping Lu ◽  
Hongwei Wang
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Temperature Field ◽  
Heat Transfer Coefficient ◽  
Heat Exchange ◽  
Thermal Insulation ◽  
Heat Insulation ◽  
Surface Heat ◽  
Surrounding Rock ◽  
Surface Heat Transfer Coefficient

High geothermal hazard is a basic problem that must be solved in deep mining; thereby the research on thermal insulation supporting for high temperature control of deep roadway is increasing. However, the quantitative analysis of its thermal insulation effect is yet to be carried out. By building the physical model and control equations of the thermal insulation supporting roadway and considering heat-humidity transfer at wall, the temperature field distribution of surrounding rock and airflow is numerically calculated. Based on numerical simulation results, the evolution law of temperature with ventilation time is analyzed at airflow inlet, outlet, and different sections, then the variation law of surface heat transfer coefficient with position and time is obtained. For heat insulation support structure, the results show that it is not obvious to change the distribution law of temperature field, but it is effective to weaken the convection heat transfer between surrounding rock and airflow. In the main airflow area, the rate of heat exchange gradually decreases with the heat exchange becoming more and more sufficient; in boundary layer, the airflow temperature quickly transits from the wall temperature to that of the main airflow area because of intense collisions of airflow masses, so the mechanism of temperature change is different. The surface heat transfer coefficient well reflected the unstable heat-humidity transfer, especially in the beginning of ventilation or at airflow inlet. Therefore, the heat insulation supporting structure is helpful to the auxiliary cooling of high temperature mine.

scholarly journals Analysis of the Thermal Characteristics of Surrounding Rock in Deep Underground Space

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Liu Chen ◽  
Jiangbo Li ◽  
Fei Han ◽  
Yu Zhang ◽  
Lang Liu ◽  
...  
Keyword(s):  
Heat Transfer ◽  
High Temperature ◽  
Thermal Characteristics ◽  
Surrounding Rock ◽  
Underground Space ◽  
Human Society ◽  
Distribution Characteristics ◽  
Air Temperatures ◽  
Rock Temperature ◽  
Deep Underground

With the development of society, the economy, and national security, the exploitation of deep underground space has become an inevitable trend in human society. However, high-temperature-related problems occur in deep underground spaces. The high temperature of deep underground space is essentially influenced by the thermal characteristics of the surrounding rock. According to the mathematical model of heat transfer of the surrounding rock in deep underground space, similar criteria numbers are established. Experiments were carried out to investigate the thermal characteristics of the surrounding rock. The distribution characteristics of temperature were determined by the Fourier number (Fo) and Biot number (Bi), and the effects of heat transfer time, airflow velocities, and air temperature and radial displacement on the distribution characteristics of temperature were studied. The results indicate that the surrounding rock temperature decreases with long heat transfer times, high airflow velocities, and low air temperatures.

Heat Transfer Model and Analysis of Oil-Immersed Electrical Transformers with Heat Pipe Radiator

2012 ◽  
Vol 516-517 ◽  
pp. 312-315
Author(s):  
Guang Hua Li ◽  
Hong Lei Liu ◽  
De Jian Wang
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Temperature Field ◽  
Heat Pipe ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Cooling Device ◽  
Transformer Design ◽  
Electrical Transformers ◽  
Good Agreement

This paper has formulated a heat transfer model for analyzing the cooling properties of a heat pipe cooling device of oil-immersed electrical transformer. Based on the model, the oil temperature field of a 30 KVA oil-immersed transformer has been numerical simulated, and experiments also had been conducted. Results showed that the numerical simulation has good agreement with experiment results. Results also showed that heat pipe radiator is feasible for oil-immersed electrical transformer cooling. The model can be used to analyze the oil temperature distribution properties in an oil-immersed electrical transformer with heat pipe cooling device, and provide theoretical guide for transformer design and improvement.

Numerical Simulation on Process of Flow and Heat Transfer in Upright Magnesium Reducing Furnace

2011 ◽  
Vol 383-390 ◽  
pp. 6657-6662 ◽  
Author(s):  
Jun Xiao Feng ◽  
Qi Bo Cheng ◽  
Si Jing Yu
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Temperature Field ◽  
Flue Gas ◽  
Gas Flow ◽  
Three Dimensional ◽  
Reaction Heat ◽  
Flow And Heat Transfer ◽  
Major Factors ◽  
High Chemical Reaction

Based on the analysis of structural characteristic superiority, the process of combustion, flue gas flow and heat transfer in the upright magnesium reducing furnace, the three dimensional mathematical model is devoloped. And numerical simulation is performed further with the commercial software FLUENT. Finally, the flow and temperature field in furnace and temperature field in reducing pot have been obtained. The results indicate that the upright magnesium reducing furnace has perfect flue gas flow field and temperature field to meet the challenge of the magnesium reducing process; the major factors that affect the magnesium reducing reaction are the low thermal conductivity of slag and the high chemical reaction heat absorption.

Numerical Analysis of the Heat Transfer in Passive Solar Composite Wall Collectors System With Porous Absorber

2007 ◽  
Author(s):  
Wei Chen
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Particle Size ◽  
Temperature Field ◽  
Room Temperature ◽  
Heating System ◽  
Thermal Insulator ◽  
Composite Wall ◽  
Unsteady Numerical Simulation ◽  
Solar Wall

In this paper, heat transfer and flow in the composite solar wall with porous absorber has been studied. The unsteady numerical simulation is employed to analyze the performance of the flow and temperature field in the composite solar wall. The excess heat is stored within the porous absorber during solar radiation and there is stratification in the porous layer. So, the porous absorber works as thermal insulator in a degree when no solar shining is available. The heating characteristic of two types of the composite solar wall with porous absorber has been conducted. The influence of particle size, porosity and porous absorber arrange in the solar composite wall on the heating room temperature is significant. The results show that all these factors should be taken into account for a better design of a heating system.

Numerical Simulation of Hot Stamping of Front Bumper

2014 ◽  
Vol 912-914 ◽  
pp. 715-722
Author(s):  
Yi Hui Guo ◽  
Ming Tu Ma ◽  
Yi Sheng Zhang ◽  
Dian Wu Zhou ◽  
Lei Feng Song
Keyword(s):  
Numerical Simulation ◽  
Temperature Field ◽  
Field Distribution ◽  
Hot Stamping ◽  
Reference Value ◽  
Cooling Channel ◽  
Test Results ◽  
Temperature Field Distribution ◽  
Channel System ◽  
Calculate Temperature Field

LS-DYNA software was adopted to conduct research of numerical simulation on hot stamping of front bumper to calculate the temperature field distribution, stress field distribution, FLD figure and etc. of parts in the course of hot stamping so as to predict and analyze the formability of parts. ProCAST software was employed to conduct research of numerical simulation on solid quenching course concerning hot stamping to calculate temperature field distribution of tools and component of multiple stamping cycles; Based on the simulation,the hot stamping mould was developed,and the front bumper components of hot forming were stamped, Compared the test results with the simulation, both the results coincide basically with same variation trend .Results obtain from numerical simulation can provide significant reference value to hot stamping part design, formability predication and tools cooling channel system design.

scholarly journals Numerical simulation of tunnel surrounding rock temperature field

2020 ◽  
Vol 587 ◽  
pp. 012043
Author(s):  
Yansong Wang ◽  
Qunshan Quan ◽  
Yuguo Zhao ◽  
Zhongzhe Zhang ◽  
Xinghong Jiang
Keyword(s):  
Numerical Simulation ◽  
Temperature Field ◽  
Surrounding Rock ◽  
Rock Temperature

Numerical Simulation of Hot Rolled Coil Temperature Field in Hot Coil Box

2011 ◽  
Vol 338 ◽  
pp. 572-575
Author(s):  
Gui Jie Zhang ◽  
Kang Li ◽  
Ying Zi Wang
Keyword(s):  
Heat Transfer ◽  
Numerical Simulation ◽  
Temperature Field ◽  
Temperature Distribution ◽  
Heat Transfer Model ◽  
Transfer Model ◽  
Coil Temperature ◽  
Hot Rolled ◽  
Strip Coil ◽  
Good Agreement

The heat transfer model was developed and the heat transfer of the strip coil stay in the hot coil box was analyzed. The temperature distribution of the strip coil was investigated use the model. The measured results are in good agreement with the calculated ones, has a guiding significance to further improve the technology.

Sign in / Sign up

Export Citation Format

Share Document