Speaker
Description
Carbon dioxide radiative prediction is an important aspect in many scientific and industrial applications. Highly accurate databases such as HITRAN \cite{GORDON20173}, HITEMP \cite{ROTHMAN20102139} or CDSD \cite{TASHKUN2003165}\cite{TASHKUN20111403} are designed to reconstruct the spectrum in a given temperature accurately. However, in the context of atmospheric entry these databases have some known drawbacks. The accuracy of these databases depends on the temperature and is gradually degraded as this temperature exceeds the one for which they were designed for.For high temperature ($T>3000$ K) conditions, the \ce{CO2} spectrum is rich in features making the size of CDSD4000 computationally prohibitive for use in full spectrum calculations while HITRAN and HITEMP cannot be used at such high temperatures. Furthermore, these databases do not separate the rotational and vibrational degrees of freedom. In the context of atmospheric entry, in the wake flow of a spacecraft, the conditions of the gas are characterized by chemical and thermodynamical non-equilibrium. Full spectrum radiative calculations are carried out to determine the amount of protection necessary in the back shell of capsules. A radiative database that is smaller and allows for non-equilibrium calculations is desirable. In this work, we propose to reduce the size of the database to make it computationally efficient. This is achieved by refitting the ro-vibrational data in databases such as HITRAN or CDSD and reorganize it as vibrationally specific database. The great advantage of the newly generated database is that it can still be applied for ro-vibrational predictions by retaining the global accuracy of the spectrum while being more portable. It can also be used for coupling vibrational state-to-state kinetics calculations, a work that as been started recently~\cite{AMAL2016}.
In this work the Carbon Dioxide Spectral Databank 4000 \cite{TASHKUN20111403} (CDSD4000) was used as source data that is to be reorganized and fitted. The obtained database is denoted CDSDvib hereafter. This work is a follow up from previous work from the authors presented previously~\cite{VARGAS2018}. While sharing similarities with the previous work the approach for selecting, processing data and the quality of the achieved results are different. The previous worked aimed for a global algorithm for refitting and processing data, this work focuses only on one spectral range and aims at a bottom up approach by a selective method for processing data.\
Summary
A new CO2 IR radiation model based on CDSD + A solution to TC1A-EXOMARS-2016 and TC2A-ShockTube-MSL
