Nonisobaric Flame Propagation

Publisher Summary This chapter focuses on nonisobaric flame propagation and describes the propagation of deflagration waves in configurations, in which the pressure undergoes significant changes. In the internal combustion engine, the deflagration phenomenon occurs in an approximately cylindrical volume of time-dependent length, and the pressure changes are central to its successful operation. Whatever the container geometry may be, the kinematics of the motion are artifacts of earlier stages of the process and are largely unknown and uncontrolled. The chapter explains the propagation of a one-dimensional flame in a cylinder, whose length is L (t), using the crudest description of the relevant processes. Turbulent flame is a thin, convoluted, laminar flame, undergoing enormous distortion and area change with time, but consuming fuel locally in a manner which is no different than that of a plane flame stretching at the same rate. Other automotive-combustion-related phenomena that can be included within formulations are blowby, stratification of the charge, and heat loss.