Future Trends in Commercial Aviation Engines’ Combustion - Novel Combustion Concepts for Sustainable Energy Development - page 156

calibration of semi-empirical correlation followed by their applications (Rizk and
Mongia 1990 ; Mongia 2010a , b ). The conceptual design of the combustion con-
cepts and their execution through engineering-based testing process are equally
important for meeting the design goals. An optimum combination of the three was
coined as empirical/analytical design methodology (viz. Mongia and Smith 1978 )
which has continuously improved through the years to the best process currently
followed by several including Rida et al. ( 2012 ), Sen et al. ( 2012 ), Sekar et al.
( 2014 ), Sripathi et al. ( 2014 ).
Our new CFD modeling approach is required for managing combustion
dynamics in addition to predicting CO and NO x . Therefore, we started with the
National Combustion Code (NCC) that solves the turbulent uid

transport equations coupled with compact kinetic scheme including turbulence
chemistry interaction. Both Reynolds-averaged Navier

two-phase fl

- Stokes (RANS) and time-

Stokes (TFNS) simulations are planned to be calibrated with the
LDI-1 and LDI-2 data before the models can be applied for screening promising
new concepts. The reader may want to refer to the publications (viz. Ajmani et al.
2013a , b , c , 2014 ; Ajmani and Breisacher 2014a , b ) for details; here we will discuss
only one

filtered Navier -

figure from Ajmani et al. ( 2014 ).
Figure 45 shows the current status in terms of experimental versus predicted
NO x for the fl flat dome (identi ed as baseline) and recessed dome, identi ed as

Fig. 45 Summary of EINO x predictions (NCC) and Experimental Data (WFST) at P 3 = 130 psia
and various cycle conditions for four different LDI-2 geometries; from Ajmani et al. ( 2014 )