Low speed tests have been carried out on a branched
diffuser, geometrically similar to that employed in some
gas turbine combustion systems. The fully annular test rig
consisted of a straight walled, axisymmetric pre-diffuser,
exhausting into a sudden expansion, the flow then being
divided into two separate streams by a bluff body simulating
the combustion chamber situated on the same centre-line as
the pre-diffuser. The overall area ratio was maintained at
2.0, and tests vJere conducted with fully developed entry
flo\~ for a range of pre-diffusers of 120 included angle, the
design value of the ratio of mass flows in the inner and
outer annuli surrounding the flame tube being fixed at 1.2.
Further tests were conducted using a single pre-diffuser, a
distorted entry velocity profile, and a design flow division
around the flame tube of 2.15....
A Master's Dissertation, submitted in partial fulfilment of the requirements of the award of the Master Of Science degree of Loughborough University.