scholarly journals EXPERIMENTAL CONFIRMATION OF THE LAWS OF THERMAL RADIATION OF GAS VOLUMES

2021 ◽  
Vol 23 (2) ◽  
pp. 189-200
Author(s):  
Anatoliy Nikolaevich Makarov
Keyword(s):  
Thermal Radiation ◽  
Experimental Confirmation

Experimental Confirmation of Avogadro’s Law for Thermal Radiation

2015 ◽  
Vol 7 (2) ◽  
pp. 1386-1392
Author(s):  
Mikhail Jakovlevich Ivanov ◽  
Vadim Konstantinovich Mamaev ◽  
Igor Viktorovich Tsvetkov ◽  
Grigoriy Borisovich Zhestkov
Keyword(s):  
Experimental Study ◽  
Pressure Drop ◽  
Thermal Radiation ◽  
Pressure Variation ◽  
Experimental Confirmation ◽  
Temperature Range ◽  
Radiation Action ◽  
Increasing Temperature

Experimental study of pressure variation in metal empty sealed container in low vacuum conditions (0.1-10 mbar) for temperature range from 290 to 1490 K is presented. Three characteristic areas of pressure variation were registered: the pressure growth in accordance with Avogadro’s law in the temperature range from 290 to 700-800 K, the pressure drop in the temperature range from 800 to 1300 K and again the intensive pressure increasing in the temperature range from 1300 to 1490 K.  Possible causes of registered pressure variation in sealed container with increasing temperature and then cooling to its original conditions were analyzed. One of the more active causes is thermal radiation action in metal empty sealed container.

Characterizing the convective heat exchange with plastic shading nets under natural arid conditions

2019 ◽  
pp. 11-20
Author(s):  
Ahmed M Abdel-Ghanya ◽  
Ibrahim M Al-Helal
Keyword(s):  
Wind Speed ◽  
Thermal Radiation ◽  
Convective Heat ◽  
Convective Heat Transfer Coefficient ◽  
Convective Heat Exchange ◽  
Radiative Properties ◽  
Wooden Frame ◽  
Arid Conditions ◽  
Air Temperatures ◽  
Radiation Fluxes

Plastic nets are extensively used for shading purposes in arid regions such as in the Arabian Peninsula. Quantifying the convection exchange with shading net and understanding the mechanisms (free, mixed and forced) of convection are essential for analyzing energy exchange with shading nets. Unlike solar and thermal radiation, the convective energy, convective heat transfer coefficient and the nature of convection have never been theoretically estimated or experimentally measured for plastic nets under arid conditions. In this study, the convected heat exchanges with different plastic nets were quantified based on an energy balance applied to the nets under outdoor natural conditions. Therefore, each net was tacked onto a wooden frame, fixed horizontally at 1.5-m height over the floor. The downward and upward solar and thermal radiation fluxes were measured below and above each net on sunny days; also the wind speed over the net, and the net and air temperatures were measured, simultaneously. Nets with different porosities, colors and texture structures were used for the study. The short and long wave’s radiative properties of the nets were pre-determined in previous studies to be used. Re and Gr numbers were determined and used to characterize the convection mechanism over each net. The results showed that forced and mixed convection are the dominant modes existing over the nets during most of the day and night times. The nature of convection over nets depends mainly on the wind speed, net-air temperature difference and texture shape of the net rather than its color and its porosity.

Sign in / Sign up

Export Citation Format

Share Document