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Спутники
РН
SpaceX
Роскосмос
NASA
СпутникиРНSpaceXРоскосмосNASAPublication date: 13 April 2026
Source: Applied Mechanics and Materials Vol. 935
Author(s): Abdullatif A. Gari
Heat losses from heating air ducts underground are used in many applications such as heating and air conditioning in cold weather. Researchers worked on heat losses to understand different ways to reduce heat losses to the environment. This project studies a 3-dimensional model of heating rectangular duct in cold surroundings. The model was done numerically. The numerical grid was tested to reach a reasonable approximation and a comparison with correlations from literature showed good agreement. Moreover, parametric study was carried out to study the effect of different parameters on heat losses. These parameters were Inlet velocity Vo, Inlet temperature To, outer heat transfer coefficient ho, and surrounding temperature T∞. Results showed that higher inlet velocity, inlet temperature, and outer heat transfer coefficient increases the total heat loss to the surroundings while higher surrounding temperature decreases the total heat loss to the surroundings.
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