Saravanan, D., Gokhale, A., and Karthikeyan, N., "Design and Development of a Flow Based Dual Intake Manifold System," SAE Int. J. Engines 8(1):68-74, 2015, doi:10.4271/2014-01-2880.
The Torque from an engine is a very critical parameter which controls the drivability of the vehicle, better torque availability at Partially Open Throttle (POT) condition improves drivability at city driving condition and better torque at Wide Open Throttle (WOT) condition improves cruising at highway driving condition, conventionally engine produces better torque at one particular operating condition leaving poor drivability at others. The Torque characteristics of an engine depends upon the volumetric efficiency of the engine. The volumetric efficiency of a naturally aspirated engine can be improved by tuning the intake manifold. With an overall improvement in volumetric efficiency throughout the engine operating conditions better torque curve can be achieved, which facilitates improved drivability.For improving volumetric efficiency, several technologies were developed and used, among that Dual Intake Manifold system is one where the flow of charge is channelized between longer and shorter flow path depending on the engine operating condition. Conventionally in Dual Intake manifold system, flow is channelized using valves which are actuated by external power sources. However the application of this system is limited due to increased cost, complexity in assembly, need of an external power source for actuation, and increased number of moving parts which in turn reduces the reliability of the system; also this system requires an actuation mechanism for operating the valve which further increases the complexity of the system.In this work a novel Dual Intake Manifold system is designed and developed which improves the torque at POT condition by making the charge to flow through the longer path and at WOT condition the charge flows through the shorter path. The flow of charge between the two paths is controlled based on the flow characteristics of charge at different operation conditions namely POT and WOT conditions. In this method no valves are used to channelize the charge, no external actuation mechanism is required and no moving parts are present, which further improves the reliability of the system. Experimental results have shown more than 47% improvement in Torque and Power at POT condition without any sacrifice of performance at WOT condition.