Author : S. M. Muzakkir and Harish Hirani

The present engine technology is required to achieve optimum performance under varying load and speed conditions imposed on the vehicle. The variable valve timing systems are employed in conventional engines to ensure optimal performance under varying operating conditions. The Variable Valve Systems (VVS) improves the gasoline-engine fuel economy and reduces emission by controlling the area, time and duration of cylinder opening. The benefits of the VVS technology are however not fully realized because the existing engine valve systems are modified by the addition of the control elements to convert it to VVS. These extensions make the valve system complex and bulky in addition to increasing the cost making it less preferable for implementation in various applications. The present paper emphasizes the design of variable valve systems starting from conceptual design phase to the final design using the axiomatic design. Axiomatic design is a systematic and scientific approach that provides future directions and enhances designers’ creativity. Using the axiomatic design, this paper presents two concepts of VVS which involve minimum number of moving parts, causes minimum power loss and provide full flexibility to actuate the valve. These proposed VVS’s have less inertia, low noise and high sealing capacity.

Keywords: Axiomatic Design, Functional requirement, Design Parameters, Design Matrix, Variable Valve System, Optimum Engine Performance, Magnetorheological Fluids

Article published in International Journal of Current Engineering and Technology, Vol.5, No.2 (April-2015)