ENGLISH ABSTRACT: The purpose of this investigation is to determine the performance of an axial
ow compressor operating in a closed loop helium cycle under high through-
ow conditions. The GTHTR300 four-stage helium test compressor was chosen
for this investigation. Limited information on the helium test compressor's
blade pro les are available, therefore a mathematical model was developed to
calculate the blade geometries based on the theory of Lieblein and Aungier.
A locally available three-stage compressor was used to con rm whether the
mathematical model calculated the blade pro le geometries correctly. The
Stellenbosch University Compressor Code (SUCC), an axisymmetric inviscid
through- ow code, was used to compare the performance of the calculated
three-stage compressor blade geometries with available experimental data. Excellent
correlation was obtained, thus it was concluded that the mathematical
model as well as the SUCC could be used to predict the performance of an
axial ow compressor. The blade geometries of the helium test compressor
were calculated and the pressure ratio and e ciency predictions of the SUCC
correlated well with the experimental data. The helium test compressor was
simulated to verify the calculated blade geometries further using the Computational
Fluid Dynamics (CFD) package NUMECA FINE /Turbo. The
FINE /Turbo pressure ratio and e ciency predictions compared adequately
with the SUCC and available experimental data, especially in the design region.
At high mass ow rates the stator blade row experiences negative incidence
stall which results in a large recirculation zone in the stator blade wake.
AFRIKAANSE OPSOMMING: Die doel van hierdie ondersoek is om vas te stel wat die werkverrigting is van 'n
aksiale kompressor in 'n geslote lus helium siklus onderhewig aan hoë deurvloei
kondisies. Die GTHTR300 vier-stadium helium toets kompressor is gekies vir
die ondersoek. Daar is egter beperkte inligting oor die helium kompressor se
lem geometrie, dus is 'n wiskundige model ontwikkel om dit te bereken gebaseer
op die werk van Lieblein en Aungier. Om te bevestig dat die lem geometrie akkuraat
was, was die lem geometrie van die 'n plaaslike beskikbare drie-stadium
kompressor bereken. Die Stellenbosch University Compressor Code (SUCC),
'n aksisimmetriese nie-viskeuse deurvloei kode, is gebruik om die prestasie van
die berekende lem geometrie met beskikbare eksperimentele data te vergelyk.
Uitstekende korrelasie is verkry vir die drukverhouding en benuttingsgraad resultate,
dus is die gevolgtrekking gemaak dat die wiskundige model sowel as die
SUCC gebruik kon word om die lem geometrie en werkverrigting van aksiale
kompressors te bereken en voorspel. Die helium toets kompressor is gesimuleer
met behulp van die numeriese vloei-dinamika pakket NUMECA FINE /Turbo
om die berkende lem geometrie verder te veri eer. Die FINE /Turbo drukverhouding
en benuttingsgraad resultate het goed gekorreleer met beide die
SUCC resultate en eksperimentele data, veral in die ontwerpsgebied. Teen hoë
massa vloei tempo's vind daar groot wegbreking teen negatiewe invalshoek
plaas in die stator lemry en dit veroorsaak 'n hersirkulasie sone in die naloop
van die stator lem.
