Stick–slip oscillations of an engine front-end accessory drive system with a mechanical tensioner

Abstract

This article is aimed to investigate the stick–slip oscillations of an engine front-end accessory drive system with a mechanical tensioner. Based on several assumptions, a generic dynamic model of rotational vibrations of an engine front-end accessory drive system with arbitrary number of accessory pulleys and one mechanical tensioner is established. In this model, the tensioner dry-friction torque is approximated by a hyperbolic tangent function with a scaling factor to control the sticking zone. An improved multiple harmonic balance method is used to solve the governing equations of rotations of the engine front-end accessory drive system and obtain the periodic rotational vibrations of the system accessory components. The calculation results obtained from the improved multiple harmonic balance method are verified by the results obtained from the Runge–Kutta integration method. Amplitude–frequency responses of rotational vibrations of the accessory components in the engine front-end accessory drive system are calculated using the arc-length technique based on the improved multiple harmonic balance method. Stick–slip oscillations of the tensioner arm with different values of the tensioner dry-friction torque are calculated and influences of the tensioner dry-friction on system rotational vibration amplitudes are analyzed. Variations of system vibration energies dissipated by the tensioner dry-friction at different crankshaft speeds with increases of the maximum tensioner dry-friction torque are calculated, and an optimum design of the tensioner dry-friction damping is given according to the results.

Steady-state and start-up transient responses of a belt-driven starter generator system for micro-hybrid electric vehicles

“…But rotation vibrations of other accessory pulleys do not monotonously decrease with increasing tensioner dry friction. This is consistent with previous conclusions (Zhu et al, 2020b) that give directions of design optimization on tensioner damping.…”

“…One of the many challenges in successfully developing a good BSG system for a micro-HEV is to maintain its noise and vibrations under different working modes within a comfortable level for passengers and ensure high efficient and reliable start–stop response. Many research studies (Čepon et al, 2009; Kraver et al, 1996; Parker, 2004; Shangguan and Zeng, 2013; Zhu et al, 2018a, 2018b, 2018c, 2020b, 2021) have been conducted on dynamics and vibrations of the traditional EFEADS, but fewer research studies (Canova et al, 2009; Chen, 2009; Feng et al, 2019; Olatunde, 2008) have been conducted on those of the engine accessory drive system with a generator starter (i.e., the BSG system). These research studies are mainly focused on improving performance and efficiency of the starter and generator.…”

Modeling of tensioner hysteresis for belt accessory drive system under random excitations

“…At present, many researchers have established models to describe the hysteresis characteristics of tensioners, which are mainly divided into physical models 2,9 and phenomenological models. [14][15][16][17][18][19][20] Physical model of a tensioner is to characterize the relations of tensioner torque versus angular displacement of tensioner arm with the geometric size of tensioner, the stiffness of tensioner spring and the friction coefficient of friction elements. The physical model is used for structural design and optimization of tensioner to determine the required tensioner torques, and finite element model is a typical physical model.…”

“…The parameters in K-V model has clear physical meaning, and it is easy to be used for calculating the dynamic response of tensioner under different excitation, but the calculation accuracy is not high. (2) Dry friction model: Regarding the internal friction of tensioner as coulomb dry friction, Zhu et al 16 and Zhao et al 17 established the dry friction model for tensioner, as shown in Figure 2(b).…”

“…The model parameters in phenomenological model are usually determined by fitting the estimated output torque of a tensioner with the measured data. The K-V model, 14,15 dry friction model, 7,16,17 Masing model, 8,18 and Duhem model 19,20 are commonly used phenomenological models at present, as shown in Figure 2.…”