ANG_Thèse_LEGRAND_LEGI_Contrôle thermodynamique d`ergol

Proposition de sujet de thèse
Domaine des sciences pour l’ingénieur appliquées aux systèmes de transport spatial
Titre du sujet : Contrôle thermodynamique d'ergol cryogénique en réservoir
Nom et Prénom du Responsable Cnes : LEGRAND Benjamin
Adresse e-mail : [email protected]
tél . : 01.80.97.74.78
Sigle de la structure : DLA/SDT/SME
Laboratoire d’accueil : LEGI (Laboratoire des Ecoulements Géophysiques et Industriels - UMR 5519 / UJF / INPG)
Adresse : 1023 rue de la piscine - Domaine Universitaire
Code Postal : 38400
Ville : ST MARTIN D'Hères
Nom et prénom du Directeur : Christophe BAUDET
Adresse e-mail : [email protected]
tél : 04.76.82.51.61
Nom et Prénom du Directeur de thèse : THIBAULT Jean-Paul & CORRE Christophe
Adresse e-mail : [email protected]
[email protected]
tél : 04.76.82.50.33
04.76.82.51.43
Nom et Prénom de l’Encadrant : THIBAULT Jean-Paul & CORRE Christophe
Adresse e-mail : [email protected]
[email protected]
tél : 04.76.82.50.33
04.76.82.51.43
Co-financeur : AIR LIQUIDE Advanced Technologies
Nom et Prénom du Responsable technique : BARBIER François
Adresse e-mail : [email protected]
tél. : 04.75.43.63.99
Nom et Prénom du Responsable administratif :
Adresse e-mail :
tél. :
Profil du candidat : Mécanique des Fluides et Energétique
Sujet : Thermodynamic control of cryogenic propellant tank
(LEGI, team EDT, Grenoble)
Projects launchers powered by cryogenic motors with important mission time (up to several weeks)
require management of propellants (hydrogen and oxygen) in tanks subjected to solar flux.
Within a tank, for a ballistic phase under low gravity, it operates a thermal stratification of both vapor
and liquid phases of the propellant that promote evaporation and therefore pressurization. By cons in
zero gravity, the liquid bath focuses on the walls of the tank, under the influence of surface tension
forces, while steam is at the center. These changing conditions make complex definition and then
evaluating a control system propellants. A possible solution for the control is to inject in the steam a
spray of the subcooled liquid propellant. This mode of control is referred to as the generic
"Thermodynamic Vent Systems" (TVS). The block diagram of such a control system (Figure 1) has a
main loop (red a-b-c) for forming the liquid propellant subcooled spray which includes: a pump, an
injection nozzle (nozzle) and a heat exchanger. The secondary loop (blue 1-2-3-4) cools and includes
a Joule-Thomson expansion valve, evaporator, superheater and an exhaust propellant under
expanded. If the main loop is activated only, it can reduce thermal stratification. If the spray sub-cooled
through the secondary loop, is injected in the steam it allows the liquefaction of a portion of the steam
through a heat and mass transfer (liquid-vapor) made by the highly efficient fine particle size of the
spray.
Figure 1: Schematic of thermodynamic control propellant
Previous phases of the project LEGI conducted with support from CNES and Air Liquide, an
experiment of thermodynamic control was designed and constructed. It uses a fluid propellant
similarity which, at atmospheric pressure, vaporizes at 50 ° C and allows the use of measurement
methods available at LEGI: visualization and image processing (high speed camera), Particle Image
Velocimetry (for mixing liquid-liquid) and particle size by laser diffraction and phase Doppler
interferometry. Measures to analyze the coupling between the dynamics of the spray and the transfer
of heat and mass, as well as between the propellant liquid and its vapor between the spray and the
liquid propellant.
Based on the balance equations a time-dependent OD model conducted in parallel with the
completion of the experiment. Performance indices were constructed to quantify the potential gains of
the control system. The first measurement campaigns show a very satisfactory agreement model /
validate the method and measures around simple cases.
The proposed PhD program will consist of several components:
- Experimentaly, a wide range of operating conditions will be explored. In addition, changes in
the experiment will be implemented according to the limits and shortcomings revealed during
the promotion.
- Modeling OD will also continue with a special effort devoted to model equations of mass
transfer, momentum and heat to various internal boundaries (interfaces) and external (wall)
system. Taking into account the coupling between, on the one hand, the dynamics and size of
the spray and, secondly, the heat and mass transfer will be essential at this stage.
- A comparison with results obtained by numerical simulation is also provided. It will be
conducted using commercial codes or using dedicated codes developed in the laboratory