Date: January 1, 1959 Description: With the assumptions that
Berthelot's equation of state accounts for molecular size and
intermolecular force effects, and that changes in the
vibrational heat capacities are given by a Planck term,
expressions are developed for analyzing one-dimensional flows of
a diatomic gas. The special cases of flow through normal and
oblique shocks in free air at sea level are investigated. It is
found that up to a Mach number 10 pressure ratio across a normal
shock differs by less than 6 percent from its ideal gas value;
whereas at Mach numbers above 4 the temperature rise is
considerable below and hence the density rise is well above that
predicted assuming ideal gas behavior. It is further shown that
only the caloric imperfection in air has an appreciable effect
on the pressures developed in the shock process considered. The
effects of gaseous imperfections on oblique shock-flows are
studied from the standpoint of their influence on the life and
pressure drag of a flat plate operatin