Simulation research on aerodynamic heat radiation of dome in complicated thermal environment

2021 ◽  
Author(s):  
Lei Gao ◽  
Huan Li ◽  
Shuang Wang ◽  
Mingna Liu
2014 ◽  
Vol 924 ◽  
pp. 329-335 ◽  
Author(s):  
Cong Hang Li ◽  
Shi Chen Jiang ◽  
Zheng Ping Yao ◽  
Song Sheng ◽  
Xin Jian Jiang ◽  
...  

Based on the nanoporous network structure features of silica aerogel, the gas-solid coupled heat transfer model of silica aerogel is analyzed, and the calculation formulas of the gas-solid coupled, the gas thermal conductivity and the heat radiation within the aerogel are derived. The thermal conductivity of pure silica aerogel is calculated according to the derived heat transfer model and is also experimentally measured. Moreover, measurements on the thermal conductivities of silica aerogel composites with different densities at ambient conditions are performed. And finally, a novel design of silica aerogel based integrated structure and thermal insulation used for withstanding the harsh thermal environment on the Martin surface is presented.


Author(s):  
Hong Jin ◽  
Liang Qiao ◽  
Peng Cui

In urban areas, local microclimate is influenced by architectural forms, which will in turn affect human comfort. Taking Daqing as an example, this article studies the microclimate of a university campus in the severe cold area in China. Based on the space features of the streets, we categorize the streets into three types: open type, semi-open type, and street-entry type. Through analysis, this article researches microclimates of the three kinds of streets, the influence of building heating on the surrounding thermal environment, the relationship between streets’ morphology features and microclimate and human comfort (physiological equivalent temperature, PET). By study and analysis, we have the following findings: for open-type streets, the average globe temperatures of streets with different orientations can reach 1.3 °C in winter because of the influence of sidewalk trees. For semi-open-type streets, streets temperature is under the influence of the locating directions of buildings. The maximum air temperature difference among streets with different building arrangements reaches 2.1 °C in winter. For street-entry-type streets, the height–width ratios and orientations of streets are related to the continuity degree of the street interfaces. The building interface acts as a heating element and affect the surrounding thermal environment by heat convection and heat radiation. Analysis demonstrates that heat convection has a more obvious effect on rising surrounding temperature than heat radiation. Buildings with higher heat radiation witness higher globe temperature. For street-entry-type streets and semi-open-type streets, the SVF (sky view factor) and L/C (plane opening rate) of streets are negatively correlated with temperature and PET, but positively correlated with wind speed. If the SVF increases 0.1, the air temperature will reduce 0.1 °C, the wind speed will increase 0.19 m/s, and the PET will reduce 0.7 °C.


2011 ◽  
Vol 71-78 ◽  
pp. 4440-4443
Author(s):  
Lei Zhang ◽  
Qing Lin Meng

In subtropical areas of China, air temperature and relative humidity were relatively high in summer, as well as the solar radiation. In the university campus, students are relatively concentrated and have more outdoor activities. Hot and humid weather conditions may cause students uncomfortable and even heat stroke. Therefore, the influences of landscape design on thermal environment should be taken into account in the process of campus planning. In this paper, the field measurement of outdoor air temperature, relative humidity, wind velocity, heat radiation and integrated hot environmental indicator namely wet bulb global temperature were carried out around the Dong Lake in South China University of Technology in typical summer days. The impacts of design methods of water, tree, grass and floor on thermal environment were analyzed.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Yijie Zhang ◽  
Juhong Jia

AbstractThe solar radiation and the conjugate heat transfer through the cabin seat fabric were investigated numerically with a focus on a comparative analysis of various fabric solar reflectance or reflectivity (SR) and inlet cooling air velocity. For this purpose, 3D compressible Reynolds-averaged Navier–Stokes equations with the low Reynolds number turbulence model were utilized to simulate the airflow in the cabin. The discrete ordinate radiation model was adopted to describe the solar radiation. The conjugate heat transfer between the airflow and the fabric seats was included. The airflow temperature, radiative heat flux, and radiative heat transfer through the fabrics in a fixed cross section were studied. The results demonstrate that the increase in fabric SR leads to the increase in energy reflected to the atmosphere, which will bring about a lower temperature on the seat fabric. The decrease in emissivity and the energy absorbed results in the lower heat transfer and heat radiation and leads to the improvement of the cabin thermal environment. The high-temperature gradient near the seat causes the forced air circulation and is beneficial for the improvement of the thermal comfort. However, the cooling effect is not so obvious near the cabin seats when the inflow speed is increased.


2014 ◽  
Vol 1016 ◽  
pp. 446-450
Author(s):  
Jia Liu ◽  
Chao Lun Wang ◽  
Yun Ze Li

Spacecraft thermal design is a process of energy management in which environmental heating plays a major role. This paper is aimed at modeling and analysis of the orbital thermal environment by considering the external heat radiation, for the inclined-LEO cubed satellite with 3-axis stabilized (to Earth state).The result indicates that the analytical model simplifies the analysis of orbital thermal environment and the absolute value of angle on inclined orbit can vary from 0 to a maximum which equals to the sum of orbit inclination and the maximum declination of the sun. Finally, for the inclined-LEO small satellite, the extreme thermal case should fully take account of the point of.


2012 ◽  
Author(s):  
Alberto Miguel ◽  
Nelson Rodrigues ◽  
Senhorinha Teixeira ◽  
Jose Teixeira ◽  
Ricardo Oliveira

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