A new gasoline internal combustion engine was designed and built by improving the cranking mechanism. Numerical simulations were also performed to optimize the cranking mechanism to achieve both a high compression ratio operation without knocking and ...
A new gasoline internal combustion engine was designed and built by improving the cranking mechanism. Numerical simulations were also performed to optimize the cranking mechanism to achieve both a high compression ratio operation without knocking and a high thermal efficiency operation. As a result, a special cranking mechanism was considered to make a rapid piston motion near TDC, leading to less heat loss and also a tolerance for knocking limit. To evaluate this new concept, a leaf-shaped gear system was employed in a test engine. As a result, indicated thermal efficiency with the gear system in compression ratio of 12 was improved by 12% compared to a conventional engine with compression ratio of 10. Moreover, the exhaust gas emissions of HC and NOx were much reduced