Abstract:
In conventional
gas turbine performance methods, components are represented
by characteristics where the 3d properties of the flow fields' are averaged providing key flow properties at component interfaces. For the design of a component,
the consideration of the 3d nature of the flow is crucial and Computational Fluid
Dynamics (CFD) is well established in the design process; however computational
challenges generally limit the application to individual components only. The fact
that each
engine component has an effect on the overall engine performance sets
a
strong incentive to link the two methods closer together. This thesis explores
the
potential benefits of the 'coordinated application of performance modelling
and CFD
through two proof-of-concept case studies.
The, research context of the first case study was high fidelity performance simulation.
A
performance simulation process With a 2d radial representation of the
low
pressure system has been developed for a high bypass turbofan. The intake
and
bypass section were represented using axial-symmetric 2d CFD modules and
radial flow
profiles were exchanged at the component interfaces to an existing 2d
radial fan model. The iteration
procedure between the two tools was performed
manually and investigated for various operating conditions. A match of the flow
data between the tools was achieved for the intake. Guidance for improvements
and an automation of the
process are also given.
The research of the second case
study involved the design of component subsystems
in an industrial application and illustrates the potential of using CFD and
performance simulation for the design of a compressor washing system; The optimisation
of a
compressor washing system for an industrial gas turbine has been
studied
using a 3d CFD model of the intake component. Due to the interaction of
droplets with the surrounding air flow, the key factors from injection system and'
the air flow demand of the
gas turbine were investigated. Boundary conditions
were
provided using a performance simulation tool which facilitated the evaluation
of relevant
operating conditions. Associated spray parameters were derived
from numerical
sensitivity studies calibrated to data from visual field inspections
and
key design parameters were provided. Improvements were suggested and
confirmed for a similar field installation. ~