This article deals with the aerothermodynamic analyses of the hypersonic diffuser of GHIBLI Plasma Wind Tunnel at CIRA (Centro Italiano Ricerche Aerospaziali). This diffuser presented an unexpected behavior not ensuring nozzle under-expanded flow in test chamber, even in several free jet conditions. This experimental evidence was investigated following two approaches. First, a literature review pointed out that the design rules, generally recommended in supersonic diffusers design, were not observed in the case of GHIBLI diffuser. Second, a simplified numerical model was introduced and validated with experimental results, performing Computational Fluid Dynamics analyses of GHIBLI diffuser. Finally, in order to enhance the pressure recovery and to obtain the desired under-expanded conditions, two new candidate designs compliant with the literature recommended values have been proposed and analyzed via CFD.
Aerothermodynamic analyses and redesign of GHIBLI Plasma Wind Tunnel hypersonic diffuser / Walter Agostinelli, Pasquale; Trifoni, Eduardo; Savino, Raffaele. - In: AEROSPACE SCIENCE AND TECHNOLOGY. - ISSN 1270-9638. - Available online 22 February 2019:(2019), pp. 1-12. [10.1016/j.ast.2019.02.023]
Aerothermodynamic analyses and redesign of GHIBLI Plasma Wind Tunnel hypersonic diffuser
Raffaele Savino
2019
Abstract
This article deals with the aerothermodynamic analyses of the hypersonic diffuser of GHIBLI Plasma Wind Tunnel at CIRA (Centro Italiano Ricerche Aerospaziali). This diffuser presented an unexpected behavior not ensuring nozzle under-expanded flow in test chamber, even in several free jet conditions. This experimental evidence was investigated following two approaches. First, a literature review pointed out that the design rules, generally recommended in supersonic diffusers design, were not observed in the case of GHIBLI diffuser. Second, a simplified numerical model was introduced and validated with experimental results, performing Computational Fluid Dynamics analyses of GHIBLI diffuser. Finally, in order to enhance the pressure recovery and to obtain the desired under-expanded conditions, two new candidate designs compliant with the literature recommended values have been proposed and analyzed via CFD.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
