This paper discusses the development of a detailed mathematical theory and its use for the design of an electronically controlled, double-acting Variable Valve Actuation (VVA) mechanism for a camless internal combustion engine, that offers a comprehensive control over the timings and the motion of the valves such that any arbitrary time-variation of the valve lift profile can be obtained at variable rotational speeds of the engine shaft. The developed theory encompasses the thermo-fluid-dynamic as well as the applied-mechanical aspects of the actuator cylinder-engine valve system performance, the dynamics of the valve actuation being characterized by parameters such as valve opening duration, peak lift and seating velocity. The prediction of the mathematical theory compares well with several experimental data sets obtained from an in-house pneumatic VVA set-up. A new design methodology is formulated for determining the appropriate dimensions of the actuator, operating thermodynamic parameters and the electronic control of the various valve events for a desired range of engine rotational speed. Several parameters in the new design philosophy are kept within acceptable ranges established from time-tested data obtained from conventional cam-based valve actuation. For example, a new pneumatic cushioning strategy has been developed that is simple, effective and energy-efficient, and is able to keep the valve seating velocity within an acceptable range (0.08–1.13 m/s). The work also discusses the implementation of several constraints that are necessary for the design of a practically viable pneumatic actuator. The evolution of a design matrix map for the electro-pneumatic VVA is quantified for the engine rotational speed varying up to 5500 rpm.
GuhaA. Optimisation of aero gas turbine engines. Aeronaut J2001; 105: 345–358.
2.
GuhaA. Effects of internal combustion and non-perfect gas properties on the optimum performance of gas turbines. Proc IMechE, Part C: J Mechanical Engineering Science2003; 217(9): 1085–1099.
3.
ReifK. Gasoline engine management systems and components. Wiesbaden, Germany: Springer Vieweg, 2015.
4.
HongHParvate-PatilGBGordonB. Review and analysis of variable valve timing strategies-eight ways to approach. Proc IMechE, Part D: J Automobile Engineering2004; 218(10): 1179–1200.
5.
SrivastavaDKDasASinghNK. Variable valve actuation systems. In: SrivastavaDKAgarwalAKDattaA, et al. (eds) Advances in internal combustion engine research. Singapore: Springer, 2018, pp.63–91.
6.
AbagnaleCMigliaccioMPennacchiaO. New mechanical variable valve actuation systems for motorcycle engines. Proc IMechE, Part C: J Mechanical Engineering Science2015; 229(4): 716–734.
7.
ClenciACHaraVStănescuN-D, et al. Analytical synthesis and computer-aided kinematic analysis of a continuously variable valve lift mechanism. Proc IMechE, Part C: J Mechanical Engineering Science2017; 231(2): 309–325.
8.
BalkwillJDGMorreyD. Dynamic analysis of rotationally flexible cam mechanisms. Proc IMechE, Part C: J Mechanical Engineering Science1999; 213(6): 537–550.
9.
SahooSSrivastavaDK. Numerical analysis of performance, combustion, and emission characteristics of PFI gasoline, PFI CNG, and DI CNG engine. Energy2023; 278: 127749.
10.
ElmagdoubAMöllerACarlsonU, et al. Freevalve: control and optimization of fully variable valvetrain-enabled combustion strategies for high performance engines. SAE technical paper 2022-01-1066, 2022.
11.
DimitrovaZTariMLanusseP, et al. Robust control for an electromagnetic actuator for a camless engine. Mechatronics2019; 57: 109–128.
12.
ShiaoYGaddePKantipudiMB. Energy-saving actuation signal for magnetorheological valve train by leveraging hysteresis effect. Energy Convers Manage X2022; 16: 100292.
13.
LiHHuangYZhuG, et al. Linear parameter-varying model of an electro-hydraulic variable valve actuator for internal combustion engines. J Dyn Syst Meas Control2018; 140(1): 011005.
14.
LouZDDengQWenS, et al. Progress in camless variable valve actuation with two-spring pendulum and electrohydraulic latching. SAE Int J Engines2013; 6: 319–326.
15.
PanJKhajepourALiY, et al. Performance and power consumption optimization of a hydraulic variable valve actuation system. Mechatronics2021; 73: 102479.
16.
WatsonJPWakemanRJ. Simulation of a pneumatic valve actuation system for internal combustion engine. SAE technical paper 2005-01-0771, 2005.
17.
MaJZhuGSchockH. A dynamic model of an electropneumatic valve actuator for internal combustion engines. J Dyn Syst Meas Control2010; 132: 1–10.
18.
TripathySDasASahuB, et al. Electro-pneumatic variable valve actuation system for camless engine: part I-development and characterization. Energy2020; 193: 116740.
19.
CopeDWrightACorcoranCJ, et al. Fully flexible electromagnetic valve actuator: design, modeling, and measurements. SAE technical paper 2008-01-1350, 2008.
20.
GiglioVIorioBPoliceG, et al. Analysis of advantages and of problems of electromechanical valve actuators. SAE technical paper 2002-01-1105, 2002.
21.
LiuLChangS. Motion control of an electromagnetic valve actuator based on the inverse system method. Proc IMechE, Part D: J Automobile Engineering2012; 226(1): 85–93.
22.
TripathySBabuMMMittalM. A machine learning based numerical approach for valve seating velocity control in an electromagnetic camless system. In: Proceedings of the ASME: internal combustion engine division fall technical conference, Virtual Conference, Online, 2021.
23.
PournazeriMKhajepourAHuangY. Development of a new fully flexible hydraulic variable valve actuation system for engines using rotary spool valves. Mechatronics2017; 46: 1–20.
24.
TripathySSrivastavaDK. A comparative assessment of performance, combustion, and emissions of a gasoline port and direct injection camless engine. Environ Prog Sustain Energy2023; 42: e13946.
25.
LiHHuangYZhuG, et al. Adaptive LQT valve timing control for an electro-hydraulic variable valve actuator. IEEE Trans Control Syst Technol2019; 27: 2182–2194.
26.
PournazeriMKhajepourAFazeliA. An efficient lift control technique in electro-hydraulic camless valvetrain using variable speed hydraulic pump. SAE Int J Engines2011; 4: 1247–1259.
27.
PournazeriMKhajepourA. Precise lift control in a new variable valve actuation system using discrete-time sliding mode control. Mech Mach Theory2016; 99: 217–235.
28.
MaJZhuGHartsigA, et al. Model-based predictive control of an electro-pneumatic exhaust valve for internal combustion engines. In: 2008 American control conference, Seattle, WA, 2008, pp.298–305.
29.
MaJStueckenTSchockH, et al. Model reference adaptive control of a pneumatic valve actuator for infinitely variable valve timing and lift. SAE technical paper 2007-01-1297, 2007.
30.
VenkateshDSelvakumarA. A novel design of pneumatic actuator for camless engines. SAE technical paper 2016-01-0099, 2016.
31.
TripathySDasASrivastavaDK. Electro-pneumatic variable valve actuation system for camless engine: part II-fuel consumption improvement through un-throttled operation. Energy2020; 193: 116741.
32.
RicherEHurmuzluY. A high performance pneumatic force actuator system: part II — nonlinear controller design. J Dyn Syst Meas Control2000; 122: 426–434.
33.
RicherEHurmuzluY. A high performance pneumatic force actuator system: part I—nonlinear mathematical model. J Dyn Syst Meas Control2000; 122: 416–425.
34.
KrivtsILKrejninGV. Pneumatic actuating systems for automatic equipments- structure and design. CRC Press: Taylor and Francis Group, Boca Raton, 2006.
35.
CarneiroJFde AlmeidaFG. Heat transfer evaluation of industrial pneumatic cylinders. Proc IMechE, Part I: J Systems and Control Engineering2007; 221(1): 119–128.
36.
TresslerJMClementTKazerooniH, et al. Dynamic behavior of pneumatic systems for lower extremity extenders. In: Proceedings of IEEE: international conference on robotics & automation, Washington, DC, May 2002, vol. 3, pp.3248–3253.
37.
BeaterP. Pneumatic drives: system design, modelling and control. Berlin, Heidelberg: Springer, 2007.
38.
BudynasRGNisbettJK. Mechanical engineering design. New York: McGraw-Hill, 2011.
39.
GuhaASmileyB. Experiment and analysis for an improved design of the inlet and nozzle in Tesla disc turbines. Proc IMechE, Part A: J Power and Energy2010; 224(2): 261–277.
40.
GuhaABoylanDGallagherP. Determination of optimum specific thrust for civil aero gas turbine engines: a multidisciplinary design synthesis and optimisation. Proc IMechE, Part G: J Aerospace Engineering2013; 227(3): 502–527.
41.
Crane. Flow of fluids through valves, fittings, and pipe. Technical paper no. 410, 1982.
42.
The MathWorks, Inc. MATLAB version: 9.13.0 R2022b, https://www.mathworks.com (2022, accessed 1 May 2023).
PournazeriMKhajepourAHuangY. Improving energy efficiency and robustness of a novel variable valve actuation system for engines. Mechatronics2018; 50: 121–133.
48.
Compressed Air and Gas Institute. Compressed Air & Gas Handbook, Compressed Air and Gas Institute, USA https://www.cagi.org/resource-library (2021, accessed 15 March 2024).
