Abstract:To investigate the effects of the number of swirler vanes and corresponding swirling air flow variation on the performance of
a concentric staged combustor, in response to the increasing technical requirements of high thrust-to-weight ratio and high temperature
rise, all computational domains of the design model were partitioned in the form of multi-block structured grid except for the computational
domain of the swirler, periodic boundary conditions of the mixed grid were set in ICEM software, and three-dimensional numerical simula?
tions were conducted. The results show that the optimum number of vanes of the three-stage swirler is 8, 10, and 15, respectively. The
amount of air flowing through each stage of the swirler in the concentric staged combustor is negatively correlated with the number of
swirler vanes. When the design fuel-air ratio is 0.045, for the optimal scheme of the concentric staged combustor, i.e. the reference scheme,
the temperature rise can reach 1300K; the OTDF (overall temperature distribution factor) can reach 0.130, which falls within the range of
0.10 to 0.15 as required by performance specifications; the RTDF (radial temperature distribution factor) can reach 0.081, meeting the
performance requirement range of 0.08 to 0.12. The relationships between the OTDF values of the outlet section of the concentric staged
combustor and the number of vanes or the amount of swirling air in each stage of the swirler at the head of the flame tube are all V-shaped,
and the relationships between the RTDF values and the number of vanes or the amount of swirling air in each stage of the swirler at the
head of the flame tube are similar to a V-shape. |