简介:The motion tracking enhancement technique
(MTE) is a recently introduced method to improve the
accuracy of tomographic PIV measurements at seeding
density higher than currently practiced. The working
principle is bas简介:The motion tracking enhancement technique
(MTE) is a recently introduced method to improve the
accuracy of tomographic PIV measurements at seeding
density higher than currently practiced. The working
principle is based on the fact that the particle field and its
projections are correlated between the two exposures.
Therefore, information from subsequent exposures can be
shared within the tomographic reconstruction process of a
single object, which largely reduces the energy lost into
ghost particles. The study follows a previous work based
on synthetic particle images, showing that the MTE technique
has an effect similar to that of increasing the number
of cameras. In the present analysis, MTE is applied to
Tomographic PIV data from two time-resolved experiments
on turbulent shear flows: a round jet at Re = 5,000
(facq = 1,000 Hz) and a turbulent boundary layer at the
trailing edge of an airfoil (Rec = 370,000) measured at
12,000 Hz. The application of MTE is extended to the case
of more than two recordings. The performance is assessed
comparing the results from a lowered number of cameras
with respect to the full tomographic imaging system. The
analysis of the jet flow agrees with the findings of
numerical simulations provided the results are scaled taking
into account the concept of MTE efficiency based on
the volume fraction where ghost-pairs (Elsinga et al.
2010a) are produced.详细>