Designing, modeling, and structural analysis of a newly designed double lobe camshaft for a two-stroke compressed air engine

Abstract With the rapid increase of urbanization and industrialization, the energy demand has expeditiously risen. The natural resources are limited and will be extinct in the next few years. If the depletion of fossil fuels continues at the same rate as it is, the world will suffer from severe energy scarcity in the nearer future. Therefore, to reduce the dependency on liquid-based petroleum fuels, there is an urgent need for alternative fuels that could compensate for diesel demand and reduce harmful emissions from the atmosphere. The paper presents the designing, modeling, and analyzing a newly designed double lobe camshaft for a compressed air engine. In this study, a 100-cc Four-Stroke SI engine manufactured by Bajaj Auto, an Indian motorcycle manufacturer, was used and tested on compressed air. The engine was modified from a conventional four-stroke to a two-stroke engine by designing a new camshaft for opening the valves at different timings. The newly designed camshaft contains axisymmetric double lobes on both the inlet and outlet cams. Thus, in one complete revolution of the crankshaft, both the valves open once, resulting in one power stroke and one exhaust stroke, eliminating the compression and intake stroke. Any modifications in the camshaft cause various changes in the stress distribution and deformation along the shaft, which should be studied to provide us vital information about the life and effectiveness of the new modified camshaft. The objective is to determine the new valve lift profile, deformation, and equivalent (Von-Mises) stress under loading conditions on the double lobe camshaft. The designing and modeling of the camshaft are done in SOLIDWORKS 2020, and structural analysis is carried out in ANSYS 2020. The maximum total deformation resulted from the analysis comes out to be 5.72 × 10-4 mm, and the maximum value of equivalent stress evaluated is 31.17 MPa.