Study of ComPressible High Speed Gas Flow in Piping System : 1st Report, Piping Systems with Bends or Elbows

Analytical study of steady-state compressible flow of perfect gas with constant heat flux and friction in constant area ducts

“…It allows taking into account the variability of the coefficients along the channel (see e.g. [11]). Engineers often apply such methodology instead of using numerical methods, although, generally, models of the complex flow systems are collections of both numerical and analytical models.…”

“…In the case of a sudden enlargement, face pressure ratio is an empirical parameter [12] of the isentropic model. In paper [11] a kinetic energy correction factor is introduced into the exact analytical solution formula of an adiabatic flow with friction. This correction factor is formulated as a ratio of the flow obeying the 1/n-th-power law and one-dimensional flow.…”

Boundary conditions modelling of one-dimensional gas flows in an internal combustion engine

“…Inlet and exhaust manifolds of internal combustion engines include a great number of bends. Initially, Morimune et al [18] considered that the pipe was made up of two linear tubular elements. These were then connected by an equation which related the pressure drop owing to the curved element.…”

Analytical solutions for one-dimensional diabatic flows with wall friction

“…The above-mentioned exact models only take into account a single flow variation effect, that is, friction or heat transfer, and, for this reason, they fall within the class of simple flows (Shapiro 1953). Because of their importance, these two models have also been extended to include the simulation of elements, such as orifices, elbows and bends (Morimune, Hirayama & Maeda 1980a), or sudden cross-section enlargements (Morimune, Hirayama & Maeda 1980b). This is obtained by including semi-empirical factors or relations, determined with the support of experimental tests, in the 1-D theoretical models used for a constant cross-section pipe.…”