Distribution Law of High Temperature Mine's Thermal Environment Parameters and Study of Heat Damage's Causes

In order to study the characteristics of indoor thermal environment in the airport terminal in Tibet Plateau with radiant floor heating in winter, a field measurement of the indoor thermal environment was conducted in Lhasa Gonggar Airport terminal 2. First, the unique climate characteristics in Tibet Plateau were analyzed through comparison of meteorological parameters in Beijing and Lahsa. The thermal environment in the terminal was divided into outer zone and inner zone as well as south zone and north zone. Thermal environment parameters including air temperature, black globe temperature, relative humidity in each zone, and inner surface temperature of envelope were measured and analyzed. Meanwhile, temperature and relative humidity in the vertical direction were measured. In addition, PMV and PPD were calculated for evaluating the thermal environment in the terminal. The findings can provide guidance for the design and regulation of thermal environment in terminals in Tibet Plateau in China.

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Temperature Field Analysis of Steel Reinforced Concrete Column in Fire

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.351-352.615 ◽

2013 ◽

Vol 351-352 ◽

pp. 615-618 ◽

Cited By ~ 1

Author(s):

Jian Hua Chen ◽

Chao Ma ◽

Jian Hua Li ◽

Qin Qian

Keyword(s):

Temperature Field ◽

Reinforced Concrete ◽

High Temperature ◽

Field Analysis ◽

Concrete Column ◽

Distribution Law ◽

Reinforced Concrete Column ◽

Element Analysis ◽

Steel Reinforced Concrete ◽

Nice Agreement

In order to analyze the mechanical properties of the remaining carrying capacity of steel reinforced concrete columns after exposure to fire, full preparations must be needed. In this paper, the numerical simulation of the temperature field of steel reinforced concrete column section was being adopted the finite element analysis software MSC.MARC to analyze. Temperature distribution law of the column cross-section in the case of uneven fire was obtained. There has a nice agreement between calculation and original test data which created the conditions for high temperature and high temperature performance analysis for SRC columns

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

Processes ◽

10.3390/pr7100711 ◽

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.

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Nonlinear Torsional Buckling of Functionally Graded Carbon Nanotube Orthogonally Reinforced Composite Cylindrical Shells in Thermal Environment

International Journal of Applied Mechanics ◽

10.1142/s1758825120500726 ◽

2020 ◽

Vol 12 (07) ◽

pp. 2050072

Author(s):

Vu Hoai Nam ◽

Nguyen-Thoi Trung ◽

Nguyen Thi Phuong ◽

Vu Minh Duc ◽

Vu Tho Hung

Keyword(s):

Carbon Nanotube ◽

Thermal Environment ◽

Cylindrical Shells ◽

Equation System ◽

Functionally Graded ◽

Distribution Law ◽

Torsional Buckling ◽

Geometrical Properties ◽

Reinforced Composite ◽

Composite Cylindrical Shells

This paper deals with the nonlinear large deflection torsional buckling of functionally graded carbon nanotube (CNT) orthogonally reinforced composite cylindrical shells surrounded by Pasternak’s elastic foundations with the thermal effect. The shell is made by two layers where the polymeric matrix is reinforced by the CNTs in longitudinal and circumferential directions for outer and inner layers, respectively. The stability equation system is obtained by combining the Donnell’s shell theory, von Kármán nonlinearity terms, the circumferential condition in average sense and three-state solution form of deflection. The critical torsional buckling load, postbuckling load-deflection and the load-end shortening expressions are obtained by applying the Galerkin procedure. The effects of temperature change, foundation parameters, geometrical properties and CNT distribution law on the nonlinear behavior of cylindrical shell are numerically predicted. Especially, the effect of orthogonal reinforcement in comparison with longitudinal and circumferential reinforcement on the torsional buckling behavior of shells is observed.

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

Modern Physics Letters B ◽

10.1142/s021798490801608x ◽

2008 ◽

Vol 22 (14) ◽

pp. 1375-1380 ◽

Cited By ~ 6

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.

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Study on the allowable fluctuation ranges of human metabolic rate and thermal environment parameters under the condition of thermal comfort

Building and Environment ◽

10.1016/j.buildenv.2016.04.008 ◽

2016 ◽

Vol 103 ◽

pp. 155-164 ◽

Cited By ~ 12

Author(s):

Changzhi Yang ◽

Ting Yin ◽

Mushu Fu

Keyword(s):

Metabolic Rate ◽

Thermal Comfort ◽

Thermal Environment ◽

Environment Parameters

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

International Journal of Metals ◽

10.1155/2015/416824 ◽

2015 ◽

Vol 2015 ◽

pp. 1-16 ◽

Cited By ~ 3

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

Thermal Science ◽

10.2298/tsci200521250h ◽

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.

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The thermal environment of sperm affects offspring success: a test of the anticipatory paternal effects hypothesis in the blue mussel

Biology Letters ◽

10.1098/rsbl.2021.0213 ◽

2021 ◽

Vol 17 (7) ◽

pp. 20210213

Author(s):

Rowan A. Lymbery ◽

W. J. Kennington ◽

Jonathan P. Evans

Keyword(s):

High Temperature ◽

Blue Mussel ◽

Thermal Environment ◽

Paternal Effects ◽

Second Stage ◽

Mediated Effects ◽

The Many ◽

Normal Offspring ◽

By Products ◽

Better Than

There has been an explosion of recent evidence that environments experienced by fathers or their ejaculates can influence offspring phenotypes (paternal effects). However, little is known about whether such effects are adaptive, which would have far-reaching implications for the many species facing rapidly changing environments. For example, some arguments suggest paternal effects might be a source of cross-generational plasticity, preparing offspring to face similar conditions to their father (anticipatory hypothesis). Alternatively, ejaculate-mediated effects on offspring may be non-adaptive by-products of stress. Here, we conduct an experiment to distinguish between these predictions, exposing ejaculates of the externally fertilizing mussel Mytilus galloprovincialis to ambient (19°C) and high (24°C) temperatures, then rearing offspring groups in temperatures that match and mismatch those of sperm. We find that, overall, high temperature-treated sperm induced higher rates of normal offspring development and higher success in transitioning to second-stage larvae, which may represent adaptive epigenetic changes or selection on sperm haplotypes. However, the progeny of high temperature-treated sperm did not perform better than those of ambient temperature-treated sperm when rearing temperatures were high. Overall, these findings offer little support for the anticipatory hypothesis and suggest instead that beneficial paternal effects may be eroded when offspring develop under stressful conditions.

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