This work presents a comprehensive numerical and analytical study of hydrodynamic and thermal processes in closed pipelines of variable diameter, taking into account terrain relief and external thermal influences. The novelty lies in an improved quasi-onedimensional model that assesses the impact of geometric parameters (diameter, inclination angle, internal roughness) and thermophysical characteristics (material thermal conductivity, ambient temperature) on the pressure and temperature distribution along the pipeline. The model was validated against SST-turbulence-model simulations and Darcy–Weisbach calculations, with a maximum deviation below 2%. Hydraulic losses were found to depend mainly on pipe diameter and flow velocity, whereas thermal losses depend on the material’s thermal conductivity and the pipeline orientation. The proposed approach provides a reliable and computationally efficient basis for predicting the energy characteristics of fluid-transport systems and optimizing thermal networks.
| Mualliflar | Ravshanov, Sh.A., Boborakhimova, M.I., Chulliev, Sh.I., Равшанов, Ш.А., Боборахимова, М.И., Чуллиев, Ш.И. |
|---|---|
| Jurnal | Ҳисоблаш ва амалий математика муаммолари |
| Nashr sanasi | 2026-07-02 |
| Son | 3 |
| Betlar | 90-103 |
| Til | Rus |
| DOI | 10.71310/pcam.3_73.2026.07 |
DOI: 10.71310/pcam.3_73.2026.07 · Maqolaning asl sahifasi
fluid flow, heat transfer, pipe flow, поток жидкости, теплопередача, течение в трубах
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