Enhanced engineered calculation of the temperature distribution in architectural glazing exposed to solar radiation

2021 ◽  
Author(s):  
Laura Galuppi ◽  
Massimo Maffeis ◽  
Gianni Royer-Carfagni
Keyword(s):  
Temperature Distribution ◽  
Solar Radiation

Non-uniform temperature distribution of the main reflector of a large radio telescope under solar radiation

2021 ◽  
Vol 21 (11) ◽  
pp. 293
Author(s):  
Shan-Xiang Wei ◽  
De-Qing Kong ◽  
Qi-Ming Wang
Keyword(s):  
Temperature Field ◽  
Temperature Distribution ◽  
Solar Radiation ◽  
Radio Telescope ◽  
Thermal Imaging ◽  
Uniform Temperature ◽  
Large Radio Telescope ◽  
Uniform Temperature Distribution ◽  
Uniform Temperature Field ◽  
Main Reflector

Abstract The non-uniform temperature distribution of the main reflector of a large radio telescope may cause serious deformation of the main reflector, which will dramatically reduce the aperture efficiency of a radio telescope. To study the non-uniform temperature field of the main reflector of a large radio telescope, numerical calculations including thermal environment factors, the coefficients on convection and radiation, and the shadow boundary of the main reflector are first discussed. In addition, the shadow coverage and the non-uniform temperature field of the main reflector of a 70-m radio telescope under solar radiation are simulated by finite element analysis. The simulation results show that the temperature distribution of the main reflector under solar radiation is very uneven, and the maximum of the root mean square temperature is 12.3°C. To verify the simulation results, an optical camera and a thermal imaging camera are used to measure the shadow coverage and the non-uniform temperature distribution of the main reflector on a clear day. At the same time, some temperature sensors are used to measure the temperature at some points close to the main reflector on the backup structure. It has been verified that the simulation and measurement results of the shadow coverage on the main reflector are in good agreement, and the cosine similarity between the simulation and the measurement is above 90%. Despite the inevitable thermal imaging errors caused by large viewing angles, the simulated temperature field is similar to the measured temperature distribution of the main reflector to a large extent. The temperature trend measured at the test points on the backup structure close to the main reflector without direct solar radiation is consistent with the simulated temperature trend of the corresponding points on the main reflector with the solar radiation. It is credible to calculate the temperature field of the main reflector through the finite element method. This work can provide valuable references for studying the thermal deformation and the surface accuracy of the main reflector of a large radio telescope.

scholarly journals An analysis of temperature distribution in solar photovoltaic module under various environmental conditions

2018 ◽  
Vol 240 ◽  
pp. 04004 ◽  
Author(s):  
Marek Jaszczur ◽  
Qusay Hassan ◽  
Janusz Teneta ◽  
Ewelina Majewska ◽  
Marcin Zych
Keyword(s):  
Heat Transfer ◽  
Temperature Distribution ◽  
Wind Speed ◽  
Solar Radiation ◽  
Environmental Conditions ◽  
Operating Temperature ◽  
Photovoltaic Module ◽  
Solar Photovoltaic ◽  
System Efficiency ◽  
Pv System

The operating temperature of the photovoltaic module is an important issue because it is directly linked with system efficiency. The objective of this work is to evaluate temperature distribution in the photovoltaic module under different environmental conditions. The results shown that photovoltaic module operating temperature depends not only on the ambient temperature or solar radiation dependent but also depends on wind speed and wind direction. It is presented that the mounting conditions which are not taken into consideration by most of the literature models also play a significant role in heat transfer. Depends on mounting type an increase in module operating temperature in the range 10-15oC was observed which cause further PV system efficiency decrease of about 3.8-6.5 %.

Numerical Simulation on Temperature Field of CFST Member under Solar Radiation

2011 ◽  
Vol 354-355 ◽  
pp. 1241-1244
Author(s):  
Yan He ◽  
Man Ding ◽  
Qian Zhang
Keyword(s):  
Numerical Simulation ◽  
Temperature Field ◽  
Temperature Distribution ◽  
Solar Radiation ◽  
Cross Section ◽  
Temperature Difference ◽  
Steel Tube ◽  
Concrete Filled Steel Tube ◽  
Nonlinear Temperature ◽  
The Cross

In this paper the temperature field of Concrete Filled Steel Tube (CFST) member under solar radiation is simulated. The results show that temperature distribution caused by solar radiation is nonlinear over the cross-section of CFST member, and it is significantly varied with time and sections, the largest nonlinear temperature difference is over 26.3°C.

Temperature Distribution and Influence Mechanism on Large Reflector Antennas under Solar Radiation

Radio Science ◽  
2017 ◽  
Vol 52 (10) ◽  
pp. 1253-1260
Author(s):  
C. S. Wang ◽  
S. Yuan ◽  
X. Liu ◽  
Q. Xu ◽  
M. Wang ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Solar Radiation ◽  
Reflector Antennas ◽  
Influence Mechanism

Numerical Assessment on Time-Varying Temperature Field of Bridge Tower under Solar Radiation

2012 ◽  
Vol 204-208 ◽  
pp. 2236-2239 ◽  
Author(s):  
Bo Chen ◽  
Wei Hua Guo ◽  
Chun Fang Song ◽  
Kai Kai Lu
Keyword(s):  
Heat Transfer ◽  
Finite Element ◽  
Temperature Field ◽  
Temperature Distribution ◽  
Solar Radiation ◽  
Ambient Air ◽  
Heat Transfer Analysis ◽  
Time Varying ◽  
Long Span ◽  
Bridge Tower

Bridge tower, time-varying temperature field, heat transfer analysis, finite element model. Abstract. Long span suspension bridges are subjected to daily, seasonal and yearly environmental thermal effects induced by solar radiation and ambient air temperature. This paper aims to investigate the temperature distribution of a tower of a long span suspension bridge. Two-dimensional heat transfer models are utilized to determine the time-dependent temperature distribution of the bridge tower of the bridge. The solar radiation model is utilized to examine the time-varying temperature distribution. Finite element models are constructed for the bridge tower to compute the temperature distribution. The numerical models can successfully predict the structural temperature field at different time. The methodology employed in the paper can be applied to other long-span bridges as well.

SOLAR-POWERED ADSORPTION REFRIGERATION CYCLE OPTIMIZATION

2016 ◽  
Vol 78 (5-8) ◽  
Author(s):  
Norhafizah Ahmad Junaidi ◽  
Tohru Suwa
Keyword(s):  
Activated Carbon ◽  
Temperature Distribution ◽  
Solar Radiation ◽  
Air Conditioning ◽  
Thermal Storage ◽  
Hot Water ◽  
Refrigeration Cycle ◽  
Uniform Temperature ◽  
Adsorption Refrigeration ◽  
Solar Powered

Solar energy is an attractive energy source among various renewable energy resources in Malaysia as relatively high solar radiation is available throughout the year. This solar energy can be utilized for air-conditioning by using solar-powered adsorption refrigeration cycle. Intermittent nature of the solar radiation leads to a challenge for continuous air-conditioning operation. In the present study, a combination of solar-powered adsorption refrigeration system and thermal storage is studied. Activated carbon-ammonia and activated carbon-methanol are the working pairs of the adsorption reaction. Analytical calculation results show that activated carbon-methanol pair indicates higher coefficient of performance (COP) than activated carbon-ammonia pair, while adsorption chiller system with hot water thermal storage has higher COP than the system with ice thermal storage. For the activated carbon-methanol case with hot water thermal storage, the COP is 0.79. Since this COP analysis is based on the ideal case with uniform temperature distribution within the reactor beds, which achieves equilibrium states at the end of the reactions. In more realistic situation, the reaction process will be terminated before reaching to the equilibrium states because of the non-uniform temperature distribution and the time required for the reaction. Transient simulation in which heat transfer and reaction equation are combined will be performed to model actual reactors.

scholarly journals Influence of Initial and Boundary Conditions on the Accuracy of the QUB Method to Determine the Overall Heat Loss Coefficient of a Building

Energies ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 284 ◽  
Author(s):  
Naveed Ahmad ◽  
Christian Ghiaus ◽  
Thimothée Thiery
Keyword(s):  
Experimental Data ◽  
Temperature Distribution ◽  
Solar Radiation ◽  
Boundary Conditions ◽  
Heat Loss ◽  
Initial Conditions ◽  
Loss Coefficient ◽  
Heating Power ◽  
Initial Power ◽  
Overall Heat Loss Coefficient

The quick U-building (QUB) method is used to measure the overall heat loss coefficient of buildings during one to two nights by applying heating power and by measuring the indoor and the outdoor temperatures. In this paper, the numerical model of a real house, previously validated on experimental data, is used to conduct several numerical QUB experiments. The results show that, to some extent, the accuracy of QUB method depends on the boundary conditions (solar radiation), initial conditions (initial power and temperature distribution in the walls) and on the design of QUB experiment (heating power and duration). QUB method shows robustness to variation in the value of the overall heat loss coefficient for which the experiment was designed and in the variation of optimum power for the QUB experiments. The variations in the QUB method results are smaller on cloudy than on sunny days, the error being reduced from about 10% to about 7%. A correction is proposed for the solar radiation absorbed by the wall that contributes to the evolution of air temperature during the heating phase.

Temperature distribution of FAST under solar radiation

2011 ◽  
Vol 19 (5) ◽  
pp. 951-958
Author(s):  
宋立强 Song Li-qiang ◽  
王启明 Wang Qi-ming ◽  
郭永卫 Guo Yong-wei
Keyword(s):  
Temperature Distribution ◽  
Solar Radiation

Temperature Distribution and Thermal Stress Analysis of Ball-Tank Subjected to Solar Radiation

2005 ◽  
Vol 127 (2) ◽  
pp. 119-122 ◽  
Author(s):  
Vishnu Verma ◽  
A. K. Ghosh ◽  
H. S. Kushwaha
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Thermal Stress ◽  
Temperature Distribution ◽  
Solar Radiation ◽  
Ambient Temperature ◽  
Research Reactor ◽  
The Finite Element Method ◽  
Large Structure ◽  
Seasonal And Diurnal Variation

The ball tank of the research reactor CIRUS is exposed to solar radiation. The ambient temperature undergoes seasonal and diurnal variation. The resulting thermal stress could be significant for the large structure. The temperature distribution has been obtained by the finite element method. The paper presents temperature distribution and the resulting thermal stress.

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