To study the effect of the film arrangement method, the cooling gas
was injected by four different injection methods forming so called radial
and tangential films either with or without gas swirl (Fig. 2). The radial
nonswirling film was obtained by injecting the coolant through 12 holes
evenly distributed around the circumference in the direction from the
periphery to the chamber axis at the right angle to the wall being cooled
(Fig. 2,
a
).
The cooling gas was injected into the radial swirling film tangentially
to the combustion chamber internal surface through 12 holes evenly
positioned around the circumference (Fig. 2,
b
).
The tangential swirling and nonswirling films differ from the radial
ones in having an additional spacer ring that deflects the coolant flow in
the direction of the main flow and directs it along the combustion chamber
wall. The spacer ring is shown with a dashed line in Fig. 2,
a
.
Fig. 2. Film arrangement methods [7]:
a
— radial nonswirling film,
b
— radial swirling film
ISSN 0236-3941. HERALD of the BMSTU. Series “Mechanical Engineering”. 2014. No. 1 83