Plasma Wind Tunnel Testing of Ultra High Temperature Ceramics: Experiments And Numerical Correlation

di Maso, Andrea (2009) Plasma Wind Tunnel Testing of Ultra High Temperature Ceramics: Experiments And Numerical Correlation. [Tesi di dottorato] (Inedito)

Full text disponibile come:

[img]PDF - Richiede un editor Pdf del tipo GSview, Xpdf o Adobe Acrobat Reader


The thesis is focused on the aerothermodynamic and oxidation behaviour of ultra-high-temperature Ceramic (UHTC) for aerospace applications. UHTC are very high temperature resistant (>2000K) materials, with good chemical inertness and mechanical properties. These materials could be used for next generation aerospace and hypersonic vehicles. The arc jet plasma wind tunnel available at the Department of Aerospace Engineering of Naples (DIAS) is able to reproduce specific total enthalpies and stagnation pressure conditions typical of atmospheric re-entry vehicles; for this reason advanced materials for hypersonic applications can be investigated. In particular, the materials behaviour at ultra high temperatures, the durability at repeated warmed up, and oxidation resistance can be analysed. The experimental procedure based on the simultaneous use of an infrared thermocamera and a dual-colour optical pyrometer allowed to take accurate measurements of the real temperature surface distributions during tests and to evaluate the spectral surface emissivity, which is a fundamental property for aero-thermal heating. Numerical models allow the simulation of the aerothermochemical and flow fields characterizing the details of the wind tunnel experiments. For example the heat flux, the chemical environment on the model, the aero-thermal heating, and the effects of the material properties on the thermal heating can be analysed in detail. The fundamental results obtained are: characterization of several UHTC models; they are original because specific properties of UHTC materials are provided for the first time. In particular the atomic recombination induced by surface catalyticity, the spectral emissivity, the oxidation behaviour and temperature resistance at temperatures in the order of 2000K. In addition, electronic micrographs and X-rays analysis of cross sections of the investigated UHTC samples after test, allowed to characterize the oxidation layer and explain the measured surface properties

Tipologia di documento:Tesi di dottorato
Parole chiave:ultra high temperature Ceramic arc jet wind tunnel
Settori scientifico-disciplinari MIUR:Area 09 Ingegneria industriale e dell'informazione > ING-IND/06 FLUIDODINAMICA
Coordinatori della Scuola di dottorato:
Coordinatore del Corso di dottoratoe-mail (se nota)
Tutor della Scuola di dottorato:
Tutor del Corso di dottoratoe-mail (se nota)
Stato del full text:Accessibile
Data:30 Novembre 2009
Numero di pagine:87
Istituzione:Università degli Studi di Napoli Federico II
Dipartimento o Struttura:Ingegneria Aerospaziale
Tipo di tesi:Dottorato
Stato dell'Eprint:Inedito
Scuola di dottorato:Ingegneria industriale
Denominazione del dottorato:Ingegneria Aerospaziale, Navale e della Qualità
Ciclo di dottorato:XXII
Numero di sistema:3832
Depositato il:20 Maggio 2010 10:32
Ultima modifica:27 Giugno 2012 12:29

Solo per gli Amministratori dell'archivio: edita il record