Laser anemometer measurements and computations for
transonic flow conditions in an annular cascade of high turning core turbine
vanes
Goldman, Louis J. (NASA Lewis Research Center,
Cleveland, OH, United States)
NASA Center for AeroSpace Information (CASI)
NASA-TP-3383 , 1993
An advanced laser anemometer (LA) was used to measure the
axial and tangential velocity components in an annular cascade of turbine
stator vanes operating at transonic flow conditions. The vanes tested were
based on a previous redesign of the first-stage stator in a two-stage turbine
for a high-bypass-ratio engine. The vanes produced 75 deg of flow turning.
Tests were conducted on a 0.771-scale model of the engine-sized stator. The
advanced LA fringe system employed an extremely small 50-micron diameter probe
volume. Window correction optics were used to ensure that the laser
beams did not uncross in passing through the curved optical access port.
Experimental LA measurements of velocity and turbulence were obtained at the
mean radius upstream of, within, and downstream of the stator vane row at an
exit critical velocity ratio of 1.050 at the hub. Static pressures were also
measured on the vane surface. The measurements are compared, where possible,
with calculations from a three-dimensional inviscid
flow analysis. Comparisons were also made with the results obtained previously
when these same vanes were tested at the design exit critical velocity ratio of
0.896 at the hub. The data are presented in both graphical and tabulated form
so that they can be readily compared against other turbomachinery
computations.
No
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Laser anemometer measurements and computations in an
annular cascade of high turning core turbine vanes
Goldman, Louis J. (NASA Lewis Research Center,
Cleveland, OH, United States); Seasholtz, Richard G.
(NASA Lewis Research Center, Cleveland, OH, United States)
NASA Center for AeroSpace Information (CASI)
NASA-TP-3252 , 1992
An advanced laser anemometer (LA) was used to measure the
axial and tangential velocity components in an annular cascade of turbine
stator vanes designed for a high bypass ratio engine. These vanes were based on
a redesign of the first-stage stator, of a two-stage turbine, that produced 75
degrees of flow turning. Tests were conducted on a 0.771 scale model of the
engine size stator. The advanced LA fringe system was designed to employ
thinner than usual laser beams resulting in a
50-micron-diameter probe volume. Window correction optics were used to ensure
that the laser beams did not uncross in passing through the
curved optical access port. Experimental LA measurements of velocity and
turbulence were obtained both upstream, within, and downstream of the stator
vane row at the design exit critical velocity ratio of 0.896 at the hub. Static
pressures were also measured on the vane surface. The measurements are
compared, where possible with calculations from a 3-D inviscid
flow analysis. The data are presented in both graphic and tabulated form so
that they may be readily used to compare against other turbomachinery
computations.
No
Digital Version Available - Order This Document
Updated/Added to NTRS: 2003-05-08
Three-component laser
anemometer measurement systems
Goldman, Louis J. (NASA Lewis Research Center,
Cleveland, OH, United States)
NASA Center for AeroSpace Information (CASI)
NASA-TP-3080 , 1991
A brief overview of the different laser anemometer (LA)
optical designs available is presented. Then, the LA techniques that can be
used to design a three-component measurement system for annular geometries are
described. Some of the facility design considerations unique to these LA
systems are also addressed. Following this, the facilities and the LA systems
that were used to successfully measure the three components of velocity in the blading of annular-flow machines are reviewed. Finally,
possible LA system enhancements and future research directions are presented.
No
Digital Version Available - Order This Document
Updated/Added to NTRS: 2003-05-08