  A recently proposed technique for improving ignition timing is investigated
for real-gas effects. A correction to the model describing the cumulative
energy effect in the presence of the shock-discontinuity interaction was done
by re-considering the RH-relations and the shock refraction equations.
Non-dissociating gas in thermal equilibrium state, with excited translational,
rotational, vibrational, and electronic degrees of freedom is considered. When
applied to N2 gas at T=3000 K, 11% density increase and 17% temperature and 7%
pressure jump decrease were found, compared to that in ideal gas. The derived
relations are largely built on experimental data thus avoiding the complexity
of careful accounting for all real gas effects and still offering satisfactory
precision levels. The main result is that in real gases the effect in the
interaction can be stronger than that in an ideal gas. The findings can be of
interest in design of efficient combustors for hypersonic systems, detonation,
space and craft design, shock-flame interaction, in astrophysics, and fusion
research.
