Mathematical modeling of nonstationary effects at flow around a single burning particle

The behavior of the resistance and heat-exchange coefficients is examined for an evaporating spherical particle in reacting high-temperature flow on the basis of numerical solution of nonstationary Navier–Stokes equations. It is shown that during the process of flow transition to a steady state the obtaining (in the presence of chemical reaction) of the negative resistance coefficient is possible. It is noted that in the nonstationary case the appearance of an intense chemical reaction zone behind the back surface of the spherical particle excites the pressure wave, the travel of which through the particle results in substantial oscillations of the resistance coefficient and, to a lesser degree, of the heat-exchange coefficient.