The Flow Field Inside a Ranque-Hilsch Vortex Tube Part I: Experimental Analysis Using Planar Filtered Rayleigh Scattering

Abstract

The flow field of a Ranque-Hilsch vortex tube is characterized experimentally. Firstly conventional probe based technology is used in order to measure inlet and outlet temperatures as well as to acquire temporally resolved wall pressure data over a wide range of operating conditions. Secondly the filtered Rayleigh scattering technique is employed in order to gather detailed temporally averaged planar information on the vortex tube's flow topology. These measurements form the basis of a detailed numerical study in part II of this contribution.

Methods to improve pressure, temperature and velocity accuracies of filtered Rayleigh scattering measurements in gaseous flows

“…With regard to the optical efficiency, an invariable R parameter cannot always be guaranteed (see e.g. [17]). As the optical efficiency is connected linearly to both terms of equation ( 2), changes in R will have a large impact on measurement uncertainties.…”

“…In [9], a revised FRS system based on frequency scanning was presented and applied on a ducted air flow. The same system was utilized to visualize the near-wall temperature field on a high-pressure combustor [10], to characterize the flow field inside a Ranque-Hilsch vortex tube [11] as well as to measure the aero-thermal properties at the outlet of a jet engine combustor under realistic operating conditions [12,13].…”

Quantitative gas property measurements by filtered Rayleigh scattering: a review

“…Citing these issues, some researchers have used continuous wave (CW) lasers, like diode-pumped solid state frequencydoubled Nd:YVO 4 lasers, to provide 532 nm illumination with linewidths less than 5 MHz at powers up to 18 W [42,43,50,[67][68][69][70]. These spectrally pure illumination sources have enabled measurements in challenging internal flow environments with a large amount of background scattering.…”

“…More recently, a group from the German Aerospace Center (DLR) implemented frequency scanning FRS in a wide variety of experiments. They have characterized flow planes inside of a bell-mouthed circular duct [67], a Ranque-Hilsch vortex tube [68], and downstream of a nozzle guide vane (NGV) cascade in a three-sector combustor simulator [94]. The DLR Reproduced from [132], with permission from Springer Nature.…”