Factor Analysis and Cooling Technology Study on the Thermal Environment of the High Temperature Mining's Working Face

2010 ◽  
Author(s):  
Wei Huang ◽  
Fengtian Yue ◽  
Jingsheng Wei ◽  
Tao Gao
Keyword(s):  
Factor Analysis ◽  
High Temperature ◽  
Thermal Environment ◽  
Technology Study ◽  
Working Face ◽  
Cooling Technology

scholarly journals Composite design and thermal comfort evaluation of safety helmet with PCM cooling

2020 ◽  
pp. 250-250
Author(s):  
Wentao Hu ◽  
Zu`an Liu ◽  
Meng Yuan ◽  
Ying Peng ◽  
Xi Meng ◽  
...  
Keyword(s):  
High Temperature ◽  
Thermal Comfort ◽  
Thermal Environment ◽  
Cooling Effect ◽  
Absorption Cooling ◽  
Temperature Environment ◽  
Cooling Technology ◽  
Fan Cooling ◽  
Change Material ◽  
High Temperature Environment

Higher temperature and humidity will adversely affect the thermal comfort of helmet users. In order to improve the comfort level of the helmet and obtain an optimal cooling helmet model, four kinds of helmet models were established by using phase-change material (PCM) heat-absorbing cooling technology and fan cooling technology. Through the air conditioning system, the working states of four kinds of helmet models in the thermal environment of 30? were simulated, and the thermal comfort of four kinds of helmet models was evaluated. The results show that: high temperature environment is an important factor affecting the cooling effect of fan helmet (b) fan, Under high temperature environment, the helmet with fan cooling technology has a certain cooling effect in the early stage, but after 30 minutes, the cooling effect becomes worse and worse. Under high temperature environment, PCM safety helmet (c) has a good cooling effect, but poor ventilation results in the excreted sweat clinging to the scalp and hair, resulting in a poor user experience. There are defects in using phase-change material (PCM) heat absorption cooling technology or fan cooling technology alone. The helmet (d) combines PCM heat absorption cooling technology with fan cooling technology, so that the cooling effect and internal thermal environment stability of the helmet are the best, and the thermal sensation of human body is the best. Therefore, the helmet (d) is an optimal design model.

Defect and Stress Reduction in High-Pressure and High-Temperature Synthetic Diamonds Using Gradient Cooling Technology

2020 ◽  
Vol 20 (5) ◽  
pp. 3358-3364 ◽  
Author(s):  
Ning Chen ◽  
Guoqing Zhang ◽  
Rui Li ◽  
Gang Xu ◽  
Fangbiao Wang ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Stress Reduction ◽  
Synthetic Diamonds ◽  
Cooling Technology

scholarly journals Study on Flow Field and Rotor Safety Characteristics of MSPs Based on Flow Thermo-Coupling

Processes ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 711
Author(s):  
Yiming Chen ◽  
Rongsheng Zhu ◽  
Yonggang Lu ◽  
Zhenjun Gao ◽  
Junjun Kang
Keyword(s):  
High Temperature ◽  
Equivalent Stress ◽  
Outer Edge ◽  
Cover Plate ◽  
Distribution Law ◽  
Maximum Deformation ◽  
Structural Intensity ◽  
Operation Conditions ◽  
Working Face ◽  
Different Temperatures

In order to obtain the structural intensity under the operation conditions of MSP (molten salt pump), the rotor component of MSP is taken as the research object. In this paper, the influence of material properties change on the structural performance of MSP at different temperatures is analyzed. The stress distribution and strain distribution of MSP rotor components under different loads are investigated, and the intensity calculation of MSP rotor system is carried out to explore whether it meets the intensity requirements under high temperature operation, which lays a foundation for the high temperature test of MSP. The results show that the maximum deformation position of the blade working face appears at the outer edge of the impeller. When the fluid-structure coupling is applied, the blade strain law and the strain law during thermo-coupling are similar. The effect of the temperature field on the degree of blade deformation is not significant, provided that other factors remain the same. The position where the impeller equivalent stress is the largest is mainly concentrated in the area where the blade is in contact with the front and rear cover plates at the outlet of the impeller. Different degrees of stress concentration occur in the area where the blade is in contact with the impeller hub. The distribution law of the equivalent stress on the surface of the impeller cover plate is that the equivalent stress value changes periodically along the circumferential direction of the impeller, and the number of change cycles is equal to the number of impeller blades. This study can provide a reference for the structural design of MSPs.

EFFECTS OF THERMAL ENVIRONMENTS ON THE THERMAL SHOCK RESISTANCE OF ULTRA-HIGH TEMPERATURE CERAMICS

2008 ◽  
Vol 22 (14) ◽  
pp. 1375-1380 ◽  
Author(s):  
WEIGUO LI ◽  
DAINING FANG
Keyword(s):  
Heat Transfer ◽  
High Temperature ◽  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Thermal Environment ◽  
Transfer Condition ◽  
Ultra High Temperature Ceramics ◽  
Thermal Environments ◽  
Shock Resistance ◽  
Ultra High Temperature

In the present study, the temperature-dependent thermal shock resistance parameter of Ultra-High Temperature Ceramics (UHTCs) was measured based on the current evaluation theories of thermal shock resistance parameters, since the material parameters of UHTCs are very sensitive to the changes of temperature. The influence of some important thermal environment parameters on the thermal shock resistance and critical temperature difference of rupture of UHTCs were studied. By establishing the relation between the temperature and the thermal or mechanical properties of the UHTCs, we found that thermal shock behavior of UHTCs is strongly affected by the surface heat transfer coefficient, heat transfer condition and initial temperature of the thermal shock.

Spontaneous Combustion Characteristics and Air Leakage Control Technology of Half Isolated Island Fully Mechanized Caving Face

2013 ◽  
Vol 718-720 ◽  
pp. 1639-1644 ◽  
Author(s):  
Yu Bing Mu
Keyword(s):  
High Temperature ◽  
Spontaneous Combustion ◽  
Coal Pillar ◽  
Combustion Characteristics ◽  
Air Leakage ◽  
Tracer Gas ◽  
Danger Zone ◽  
Working Face ◽  
High Temperature Area ◽  
Safe Mining

The 3-105 half isolated island fully mechanized caving face in Tengdong coal mine which in complex geological and high temperature condition, has a spontaneous combustion feature that is different from normal advancing mechanized caving face, such as slowly advance speed, stress concentration and air leakage of inside-impending gob. To overcome the dangerous possibility of spontaneous combustion between the roof coal seam inside-impending gobs, small coal pillar and adjacent gob of half isolated island fully mechanized caving face, analysis spatial structure of overlying strata roof and spontaneous combustion characteristics. Based on the result of pressure can be measured and tracer gas test of air leakage channels, determine the potential air leakage areas. The MEA plugging wind material is pumped into roadway and SPA-4 plugging wind material is spray around known air leakage or high temperature area to eliminate the hazards of spontaneous combustion of the potential danger zone, and protects the safe mining of the working face.

Study on the Technique to Control Heat-Damage in Mine

2012 ◽  
Vol 577 ◽  
pp. 155-158
Author(s):  
Kai Zhang ◽  
Jing Shi Shang ◽  
Bin Tang ◽  
Ping Ye Guo
Keyword(s):  
High Temperature ◽  
Working Environment ◽  
Deep Mining ◽  
Circulating Water ◽  
Cold Source ◽  
Long Time ◽  
Mine Discharge ◽  
Cooling Technology ◽  
Deep Geothermal Energy ◽  
Source Form

With the increasing of exploitation scope and intensity, the deep mining would be the essential choice, where the heat-harm of high temperature becomes one of the main barriers. Through analyzing the thermal damage feature, the cooling technology were be used that put the mine discharge as cold source to control the heat harm. By disposing three main workstation, the technology can be accomplishes its operations and corresponding functions in different exploitation level. Particularly, the exchanged heat source form the workplace is taken to ground heating by the circulating water which being acted as a carrier. It show that the design concept of this technology include protect the environment and reduce the emission of deleterious air. The results of the project illustrate that the technology to control the heat-harm is efficient. The temperature of the workplace is brought down to 26-29 centigrade, and is 4-6 centigrade lower than the original, and the relative humidity is 5-15﹪ lower than before. It is greatly improves the working environment of the workplace where the heat-harm of high temperature and high humidity lasts for a quite long time. In addition， it extracts deep geothermal energy successful replacing ground fired boiler for heating, further reducing environmental pollution.

scholarly journals Response of Functionally Graded Material Plate under Thermomechanical Load Subjected to Various Boundary Conditions

2015 ◽  
Vol 2015 ◽  
pp. 1-16 ◽  
Author(s):  
Manish Bhandari ◽  
Kamlesh Purohit
Keyword(s):  
High Temperature ◽  
Boundary Conditions ◽  
Thermal Loading ◽  
Thermal Environment ◽  
Shear Deformation Theory ◽  
Light Metal ◽  
Functionally Graded ◽  
Numerical Results ◽  
Element Formulation ◽  
Power Law Distribution

Functionally graded materials (FGMs) are one of the advanced materials capable of withstanding the high temperature environments. The FGMs consist of the continuously varying composition of two different materials. One is an engineering ceramic to resist the thermal loading from the high-temperature environment, and the other is a light metal to maintain the structural rigidity. In the present study, the properties of the FGM plate are assumed to vary along the thickness direction according to the power law distribution, sigmoid distribution, and exponential distribution. The fundamental equations are obtained using the first order shear deformation theory and the finite element formulation is done using minimum potential energy approach. The numerical results are obtained for different distributions of FGM, volume fractions, and boundary conditions. The FGM plate is subjected to thermal environment and transverse UDL under thermal environment and the response is analysed. Numerical results are provided in nondimensional form.

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