Dissertation/ Thesis
Stability analysis of a compact steam generator exchanger ; Analyse de la stabilité d'un échangeur générateur de vapeur à plaques
| العنوان: | Stability analysis of a compact steam generator exchanger ; Analyse de la stabilité d'un échangeur générateur de vapeur à plaques |
|---|---|
| المؤلفون: | Rudkiewicz, Martin |
| المساهمون: | Institut de mécanique des fluides de Toulouse (IMFT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Université de Toulouse, Franck Plouraboué, Gérald Debenest |
| المصدر: | https://theses.hal.science/tel-04584313 ; Mécanique des fluides [physics.class-ph]. Université de Toulouse, 2024. Français. ⟨NNT : 2024TLSEP016⟩. |
| بيانات النشر: | HAL CCSD |
| سنة النشر: | 2024 |
| المجموعة: | Université Toulouse III - Paul Sabatier: HAL-UPS |
| مصطلحات موضوعية: | Instabilities, Microchannel, Heat exchanger, Multiphase flows, Conjugated heat transfers, Steam generator, Ecoulements diphasiques, Microcanaux, Transferts couplés, Générateur de vapeur, Instabilités, Echangeur thermique, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph] |
| الوصف: | In the context of greenhouse gases reduction, an increasing attention is dedicated to carbon–free power plants solutions. To answer to this growing demand, tiny nuclear reactors or Small Modular Reactors (SMR), are being developed such as the 170Mwe Pressurized Water Reactor within the NUWARD project. This technology is downscaled, modular, with a very compact Steam Generators (SG) design in comparison to current recirculating SG. Moreover, the secondary fluid is vaporized through one unique passage in millimetric channels. However, such devices potentially include static (Ledinegg) and dynamic (density wave oscillations, …) two-phase flow instabilities. These instabilities can alter the SG’s efficiency, lifetime, and even integrity from modifying the temperature, mass flow and pressure levels. Consequently, it justifies a more precise analysis and understanding of the instability’s mechanism. In this PhD, a thorough study of the Ledinegg instability and the flow maldistribution phenomenon is carried out in the compact plates SG’s operating conditions. In a capillary dominated regime we consider a localized, infinitesimally thin interfacial front plunged into a forced longitudinal temperature gradient whereby vaporization arises leading to successive liquid-gas phases distribution within the channel. Whereas the liquid and vapor velocity profiles are provided by the Poiseuille’s law, the temperature fields in the solid and the fluid are obtained using the generalized Graetz modes method, specifically adapted to the considered vaporization model. The generalized Graetz modes decomposition permits a semi-analytical solution of the 3D convection-diffusion problems provided that the velocity field, domain’s section and Peclet’s number are longitudinally invariant along the flow direction. In the first chapter, this methodology is used to analyse heat transfers in single-phase natural convection circulation loop. A new universal scaling law for the relation between the Grashof and the Reynolds numbers is obtained, ... |
| نوع الوثيقة: | doctoral or postdoctoral thesis |
| اللغة: | French |
| Relation: | NNT: 2024TLSEP016; tel-04584313; https://theses.hal.science/tel-04584313; https://theses.hal.science/tel-04584313/document; https://theses.hal.science/tel-04584313/file/RUDKIEWICZ_Martin_2.pdf |
| الاتاحة: | https://theses.hal.science/tel-04584313 https://theses.hal.science/tel-04584313/document https://theses.hal.science/tel-04584313/file/RUDKIEWICZ_Martin_2.pdf |
| Rights: | info:eu-repo/semantics/OpenAccess |
| رقم الانضمام: | edsbas.3ED77D37 |
| قاعدة البيانات: | BASE |
| الوصف غير متاح. |