Combined Effects of Variable Intake Manifold Length, Variable Valve Timing and Duration on the Performance of an Internal Combustion Engine

Abstract

Naturally aspirated internal combustion (IC) engines with a fixed intake assembly are generally tuned to produce an induction boost at a single engine speed by capitalizing the induction pressure waves only over a narrow speed range. This paper investigates the individual and combined effects of varying intake runner length and intake valve timing on the performance parameters of an IC engine at engine speeds from 3000 rpm to 9000 rpm. The 1-D model of the KTM SI engine built for simulations in Ricardo Wave software is validated with 98% accuracy against experimental test results. The performance parameters thus obtained, as a combined effect, show an average improvement of 7.02% throughout the engine’s speed range. With the co-existence of variable length intake runners and variable intake valve opening timing, the required number of variations to boost the engine performance are found to be reduced making variable intake assembly more feasible.

Exhaust Tuning of an Internal Combustion Engine by the Combined Effects of Variable Exhaust Pipe Diameter and an Exhaust Valve Timing System

“…To validate the data gathered from the 1-D simulation in Ricardo WAVE software, the engine fitted into a FSAE car is tested on a chassis dynamometer from 5500 to 7500 rpm. Brake torque and power are compared between the dynamometer and the simulation as shown in Figure 5 [15,37,41]. The nature of the brake torque and power curves obtained from the dyno test and simulation followed closely and a variance of around 5% is observed.…”

“…The optimal cross-section area of flow would be a function of engine speed. Hence, varying the flow cross-section area i.e., the exhaust pipe diameter with respect to engine speed will provide more effective control on these pressure waves and provide a boost to the engine performance [10,15,37].…”

“…However, this does not mean that the exhaust system does not possess the capability to effect on the engine performance [10][11][12]. Pressure waves in the fluid formed at the exhaust valve are highly dependent on the geometry and the overall design of the exhaust manifold [13][14][15]. With proper adjustments to the exhaust manifold, the engine performance can achieve noticeable improvements.…”

“…Engine performance vs engine speed-simulation results validated against experimental torque[15,37,41], (a) Engine power (b) Engine torque.…”

Material Properties Analysis with Addition of Nanofibres for Air Intake Filtration in Internal Combustion Engines

“…In [14], the individual and combined influence of the variable length of the inlet channel and inlet valves timing on the parameters of internal combustion engine at rotational speeds from 3000 rpm to 9000 rpm was examined. The combined effect obtained in this way shows an average power improvement of 7.02% over the entire engine speed range.…”