Design, analysis, and experimentation of a micro internal combustion swing engine.

Conventional batteries, either chemical cells or solar cells, are the only electrical power sources for portable electronics in use today. However, the limited energy density and poor performances of these batteries, both currently and for the foreseeable future, have been major concerns and problems for further technological advancement. Developing a micro engine based power generator has been one of the most promising approaches to resolve the urgent need for higher energy density power sources. In this work, a new Micro Internal Combustion Swing Engine (MICSE) that is specifically designed to serve as a portable power generator has been introduced and thoroughly investigated. The feasibility of the MICSE concept has been examined through both theoretical analysis and prototype testing. After taking into account the unique characteristics of the MICSE, detailed timing control strategies have been developed, and a complete mathematical model for the four-stroke MICSE has been derived for the steady state cycle and cold-start simulations. Simulation results have illustrated that with a hydrogen/air mixture equivalence ratio of 0.3 and a chamber pressure of 1 atm, the MICSE is capable of cold-start and achieves sustained operation only relying on the combustion processes of the initially filled fresh charges. Furthermore the device has shown several thousands times greater energy density compared to the theoretical capacity of the best conventional battery. To further enhance the conclusion drawn from the theoretical analysis, a MICSE device with the overall dimensions of 2.4&inches; x 2.4&inches; x 1.325&inches; (60.96mm x 60.96mm x 33.66mm) has been designed and fabricated with the expectation of generating up to 175 Watt of electrical power. The system has been tested with hydrogen as a fuel source with both in-chamber mixture formation through parallel induction techniques and pre-chamber mixture formation with a proportioner. Test results have demonstrated the tremendous potential of the micro engine based power generator.PhDApplied SciencesElectrical engineeringMechanical engineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/132842/2/9990944.pd