Determination of the Dynamic Reactions
for a Variable Compression Ratio
Mechanism
Bogdan M˘ anescu, Nicolae-Doru St˘ anescu , Dinel Popa,
and Nicolae Pandrea
Abstract We refer to a realistic variable compression ratio mechanism for which we
determine the kinematic and dynamic parameters of the motion. As input parameter,
we consider the position of one end of the lever which modifies the compression
ratio. For this mechanism, we draw the variation of the characteristic parameters in
function of the rotation angle of the crankshaft.
1 Introduction
The studies of such mechanism [1–8, 13–17] discuss the effects of variable compression mechanisms on the performances of the engines [3, 5, 14–18], different kinematic [4, 6, 8], or dynamic aspects [1, 7] highlighting the advantages of using of
them. The possible variants of the realization of these mechanisms [2] are more than
one thousands. The mechanism studied in this paper was firstly rejected by Freudenstein and Maki [2] because of its complexity, but nowadays it is successfully used
by Nissan and PSA.
Some aspects concerning the kinematic and dynamic behavior of this mechanism
are presented in [9–13].
2 Kinematic Analysis
The mechanism is captured in Fig. 1. It consists of the crank OA, schematized as a
homogenous bar, the triangular homogenous shell ABC, the tiller BD also considered
as a homogenous bar, the piston positioned at the point D, and the control lever CE,
schematized as a homogenous bar. By vertical displacement of point E, one may
B. M˘ anescu · N.-D. St˘ anescu (B) · D. Popa · N. Pandrea
University of Pitesti, 110040 Pitesti, Romania
e-mail: s_doru@yahoo.com
© Springer Nature Switzerland AG 2021
N. Herisanu and V. Marinca (eds.), Acoustics and Vibration of Mechanical
Structures—AVMS 2019, Springer Proceedings in Physics 251,
https://doi.org/10.1007/978-3-030-54136-1_8
75
for a Variable Compression Ratio
Mechanism
Bogdan M˘ anescu, Nicolae-Doru St˘ anescu , Dinel Popa,
and Nicolae Pandrea
Abstract We refer to a realistic variable compression ratio mechanism for which we
determine the kinematic and dynamic parameters of the motion. As input parameter,
we consider the position of one end of the lever which modifies the compression
ratio. For this mechanism, we draw the variation of the characteristic parameters in
function of the rotation angle of the crankshaft.
1 Introduction
The studies of such mechanism [1–8, 13–17] discuss the effects of variable compression mechanisms on the performances of the engines [3, 5, 14–18], different kinematic [4, 6, 8], or dynamic aspects [1, 7] highlighting the advantages of using of
them. The possible variants of the realization of these mechanisms [2] are more than
one thousands. The mechanism studied in this paper was firstly rejected by Freudenstein and Maki [2] because of its complexity, but nowadays it is successfully used
by Nissan and PSA.
Some aspects concerning the kinematic and dynamic behavior of this mechanism
are presented in [9–13].
2 Kinematic Analysis
The mechanism is captured in Fig. 1. It consists of the crank OA, schematized as a
homogenous bar, the triangular homogenous shell ABC, the tiller BD also considered
as a homogenous bar, the piston positioned at the point D, and the control lever CE,
schematized as a homogenous bar. By vertical displacement of point E, one may
B. M˘ anescu · N.-D. St˘ anescu (B) · D. Popa · N. Pandrea
University of Pitesti, 110040 Pitesti, Romania
e-mail: s_doru@yahoo.com
© Springer Nature Switzerland AG 2021
N. Herisanu and V. Marinca (eds.), Acoustics and Vibration of Mechanical
Structures—AVMS 2019, Springer Proceedings in Physics 251,
https://doi.org/10.1007/978-3-030-54136-1_8
75