Velocity Imaging of Highly Turbulent Gas Flow

Abstract

We introduce a noninvasive, quantitative magnetic resonance imaging (MRI) wind-tunnel measurement in flowing gas (>10 m s(-1)) at high Reynolds numbers (Re>10(5)). The method pertains to liquids and gases, is inherently three dimensional, and extends the range of Re to which MRI is applicable by orders of magnitude. There is potential for clear time savings over traditional pointwise techniques. The mean velocity and turbulent diffusivity of gas flowing past a bluff obstruction and a wing section at realistic stall speeds were measured. The MRI data are compared with computational fluid dynamics.

Magnetic resonance velocity imaging of liquid and gas two-phase flow in packed beds

“…Previous reports of imaging thermally polarised gases in reaction engineering systems include 1 H imaging of thermally polarised acetylene, propane and butane flowing in monolithic alumina catalysts [11] and 19 F purely phase encode imaging of highly turbulent gas flow [12]. We also note for completeness that the combination of 1 H and 19 F imaging to study dynamic multiphase systems has also been employed by Beyea et al [13].…”

Process tomography and estimation of velocity fields

“…The first MRI flow images were suitable only for a limited number of applications due to the long measurement times (Daidzic, Schmidt, Hasan, & Altobelli, 2005;Elkins, Markl, Pelc, & Eaton, 2003;Newling et al, 2004;Sederman, Johns, Alexer, & Gladden, 1998). The temporal resolution of the MRI technique has been improved dramatically in recent years through the introduction of new measurement protocols and advanced image reconstruction techniques (Anadon, Sederman, & Gladden, 2006;Gladden et al, 2006;Holland, Malioutov, Blake, Sederman, & Gladden, 2010;Muller et al, 2007;Sankey, Holl, Sederman, & Gladden, 2009;Sederman, Mantle, Buckley, & Gladden, 2004;Tayler, Holl, Sederman, & Gladden, 2010;Tayler, Holl, Sederman, & Gladden, 2012).…”

The capturing of turbulent gas flows using multiple Kinects

“…Another approach by Prasad and Sreenivasan [16] produces scalar fields of turbulent flows exiting a jet nozzle by employing an energy minimization on the pixel intensity of captured flourescent fluid in water using block matching. concerned with the capturing of wakes and turbulances was introduced by Newling et al [15]. However, all methods can be either categorized as invasive, using seeding particles, or non-invasive, relying on laser-doppler-effects or elaborated pattern analysis.…”