Design and Implementation of Waverotor Technology for Small Bore Two-Stroke Internal Combustion Engines

摘要

At high altitudes small two-stroke internal combustion engines lose power. This has been previously attributed to the reduction in ambient pressure of the intake air. One methodology to combat this effect is to implement a pressure wave supercharger (PWS) for these small-bore engines. Waverotors boost the inlet pressure to an engine by utilizing the elevated pressure of the exhaust stream to compress the ambient air. This investigation designed a scaled waverotor for a 95 cc two-stroke engine. The design of a rig to support the testing and performance validation of such a device is also explored. A previously validated one-dimensional computational fluid dynamics (CFD) code enabled the scaling of a PWS design similar to the Comprex® waverotor to the small scales associated with interfacing to the two-stroke 95 cc Brison engine.. Through CFD, simulations of a properly scaled rotor were accomplished resulting in a 1.6 in. long rotor with a design speed of 34,500 rpm. This rotor will be capable of providing up to a 50% increase in mass flow for the engine by subsequently boosting the inlet pressure by up to 135%. This elevated inlet pressure will enable the engine to perform as if it was closer to ground level, thus reclaiming its sea level power output. The following paper details the design process used to design and simulate the rotor, as well as the projected methodology for testing the overall PWS and validating the simulations relevant to the design.