*Result*: Design, Modeling and Simulation of an Improved Spherical Shaped Rotary Valve with Spindle Port for an Internal Combustion Engine.
*Further Information*
*Internal combustion engines have undergone a notable evolution, progressing from early 19th-century prototypes to today's sophisticated designs. This journey has been characterized by advancements in efficiency and power through innovations like fuel injection, turbocharging, and variable valve timing. Additionally, improvements in materials technology have resulted in lighter and more durable engines, promoting environmental sustainability. Rotary valves for internal combustion engines have made several advancements in design, innovation, and refinement. Initially conceived as experimental alternatives to traditional poppet valves, early rotary designs encountered challenges related to sealing and durability. However, through persistent research and engineering efforts, modern rotary valve systems have overcome these obstacles, delivering improved engine performance and efficiency. This research introduces a novel engine construction featuring a servo motor driven, spherical shape, spindle port rotary valve design. The engine employs both intake and exhaust rotary valves to regulate gas exchange, replacing conventional poppet valves and camshafts. The paper outlines the basic mechanism and working principle of this system. The calculations of the valve opening area demonstrate the system's benefits, showing a 20% increase compared to the previously published rotary valve design, with the new port shape facilitating a 3% faster valve opening during motion. Engine and volumetric efficiency simulations are conducted using Python programming, with both the in-cylinder pressure curve and instantaneous volumetric efficiency curve aligning with expectations. The results demonstrate an improvement in the efficiency for engine speeds below 4000 rpm compared to an engine with a conventional poppet valve design, and it offers advantages including a simple structure, fewer parts, and robust ventilation capacity. [ABSTRACT FROM AUTHOR]*