Performance parameters assessment of a pneumatic engine for low capacity commercial vehicles

In the present work, the performance evaluation of a low capacity pneumatic engine is shown, through modeling and simulation in
order to identify the feasibility of its application in commercial vehicles for short distances. For the modeling of the pneumatic engine,
the main contribution in this work is that a comprehensive approach has been used including the compressed air supply pipe, the
cylinder compression-expansion chamber, and the intake and exhaust valves. The compressed air supply system is modeled using
compressible fluid flow models. The fluid flow is considered adiabatic represented by the model known as Fanno flow (or nonisentropic)
and it is assumed to be in a steady state. The flow in the opening and exhaust valves are evaluated as adiabatic and isentropic
fluid, using a divergent-convergent compressible fluid model. The simulation results show that the feeding pressure and the
pipe diameter have a great influence on the motor power. Also, the compression ratio has been found to have strong influence on
the overall system efficiency. On the other hand, the simulations show that the initial pressure of the piston does not have a great
influence on performance indicators, such as power or efficiency. However, from the results found in this work, it can be seen that
the model and all the obtained results can be used to design and generate an optimization model that describes a pneumatic engine
proposed for commercial vehicles of low capacity and short distances.