Conveners
Numerical Simulations
- Christian Mundt
- Louis Walpot (ESA/TEC-MPA)
Numerical Simulations
- Thierry Magin (von Karman Institute for Fluid Dynamics)
Numerical Simulations
- Markus Fertig
Numerical Simulations
- James Merrifield (Fluid Gravity Engineering)
Laser breakdown is observed when a high-intensity laser beam is focused into a small region of gas. The discharge is composed of two stages: (a) creation of the priming electrons, and (b) formation of a highly conductive and absorbing plasma. This initial phase is then followed by a post-discharge, characterized by the formation and propagation of a shock wave from the focal region. The...
Background
Upcoming missions to Mars considered by JAXA generate strong motivation in designing advanced thermal protection systems (TPSs) with low design margins, in an effort to reduce the launching costs and increase the scientific value of the mission by embedding larger payloads and to enhance the reliability and safety of the reentry systems. The sizing of the TPSs relies on...
Abstract
Radiation processes are important for the description and understanding of plasma phenomena, since the radiative heat flux on the capsule can be substantial [1]. Experimental measurements are often complicated for several reasons. An alternative is the numerical simulation. Here, the common approach is the coupling of a CFD method with a radiation solver and a radiation...
1. Introduction
Computational Fluid Dynamics (CFD) represent the most cost-effective tool to characterize re-entry flows aiming at providing an accurate prediction of engineering inputs (e.g. surface heat fluxes) for the design of TPS and the overall success of space missions. The vast majority of state-of-the-art CFD codes tackling hypersonic applications rely on...
1. Introduction
Hypersonic aerothermodynamics (ATD) involves a plethora of complex physical phenomena. The harsh environment within the post-shock region produces a significant effect on the flow where fluid properties such as specific heat, viscosity and thermal conductivity can no longer be considered constant as in traditional aerodynamics. Instead they vary with temperature,...
Previous investigations have demonstrated how flowfield modelling can effect predicted level of radiation on a prospect future demonstrator-vehicle concept entering at hyperbolic velocity (Merrifield 2014). Thus far, sensitivities within the radiation database have only be briefly examined (Joiner 2015) by comparing PARADE and NEQAIR radiation databases. A significant difference uncovered in...
We present a reinvestigation of the Galileo 1995 Jupiter entry, where we attempt to reinvestigate the question of the excessive heating at the shoulder, which is postulated to occur due to radiative heating.
We consider two improvements to the radiative model: H2 molecular systems contributions to the plasma emission and absorption coefficients are accounted for, and a ray-tracing model...
The paper is focused on the state-to-state kinetics modeling the dissociation and ionization of hydrogen in high-enthalpy shock tubes. The model determines the rate coefficients of electron impact processes from the non-equilibrium electron energy distribution function (eedf) obtained solving the Boltzmann equation.
Entry computations for Martian atmosphere yield to significant radiative heat loads. CO2 is the main constituent of this atmosphere and a complex molecule. This molecule and its dissociative products have the ability to strongly emit and absorb radiative heat loads. In fact, previous investigations [1] revealed radiative heating to be crucial not only for the stagnation point region but also...
Sending a manned mission to Mars is often viewed as one of next steps in space exploration. Naturally, all the challenges associated with this endeavour must be well-understood in order to sustain a permanent human presence. One of these challenges is the creation of a breathable environment. In this work, it is argued that a sustainable oxygen supply in Mars can be achieved by converting...