95 citations · 450 across the 43 of their papers we have counts for
25 papers · 1 filter
Transition to chaos and escape phenomenon in two degrees of freedom oscillator with a kinematic excitation
Marek Borowiec, Grzegorz Litak
We study the dynamics of a two-degrees-of-freedom (two DOF) nonlinear oscillator representing a quartercar model excited by a road roughness profile. Modelling the road profile by…
Nonlinear dynamics of a regenerative cutting process
Grzegorz Litak, Sven Schubert, Guenter Radons
We examine the regenerative cutting process by using a single degree of freedom non-smooth model with a friction component and a time delay term. Instead of the standard Lyapunov e…
Intermittent behaviour of a Cracked Rotor in the resonance region
Grzegorz Litak, Jerzy T. Sawicki
Vibrations of the Jeffcott rotor are modelled by a three degree of freedom system including coupling between lateral and torsional modes. The crack in a rotating shaft of the rotor…
Cracked rotor vibrations by multifractal analysis
Grzegorz Litak, Jerzy T. Sawicki
Multifractal analysis has been used to diagnoze cracked and healthy rotors. Is has been shown that the complexity and regularity criteria of the dynamical systems defined by the mu…
Combustion Process in a Spark Ignition Engine: Analysis of Cyclic Maximum Pressure and Peak Pressure Angle
G. Litak, T. Kaminski, J. Czarnigowski +2
In this paper we analyze the cycle-to-cycle variations of maximum pressure and peak pressure angle in a four-cylinder spark ignition engine. We examine the exp…
Response of a Magneto-Rheological Fluid Damper Subjected to Periodic Forcing in a High Frequency Limit
Marek Borowiec, Grzegorz Litak, Rafal Kasperek
We explored vibrations of a single-degree of freedom oscillator with a magneto-rheological damper subjected to kinematic excitations. Using fast and slow scales decoupling procedur…
Stochastic description of the deterministic Ricker's population model
Arkadiusz Syta, Grzegorz Litak
We adopt the '0-1' test for chaos using Brownian motion chains to identify the dynamics of the Ricker's population model. In the '0-1' test '0' is related to regular motion while '…
Homoclinic transition to chaos in the Ueda oscillator with external forcing
Grzegorz Litak, Arkadiusz Syta, Marek Borowiec
We examine the Melnikov criterion for transition to chaos in case of a single degree of freedom nonlinear oscillator with the Ueda well potential and an external periodic excitatio…
Phase lock and rotational motion of a parametric pendulum
Grzegorz Litak, Marek Borowiec, Marian Wiercigroch
The effect of noise on a rotational mode of a pendulum excited kinematically in vertical direction has been analyzed. We have shown that for a weak noise transitions from oscillati…
Wavelet Analysis of Cycle-to-Cycle Pressure Variations in an Internal Combustion Engine
Asok K. Sen, Grzegorz Litak, Rodolfo Taccani +1
Using a continuous wavelet transform we have analyzed the cycle-to-cycle variations of pressure in an internal combustion engine. The time series of maximum pressure variations are…
Vibration of the Duffing Oscillator: Effect of Fractional Damping
Marek Borowiec, Grzegorz Litak, Arkadiusz Syta
We have applied the Melnikov criterion to examine a global homoclinic bifurcation and transition to chaos in a case of the Duffing system with nonlinear fractional damping and exte…
Transition to Chaos in the Self-Excited System with a Cubic Double Well Potential and Parametric Forcing
Grzegorz Litak, Marek Borowiec, Arkadiusz Syta +1
We examine the Melnikov criterion for a global homoclinic bifurcation and a possible transition to chaos in case of a single degree of freedom nonlinear oscillator with a symmetric…
Pulsive feedback control for stabilizing unstable periodic orbits in a nonlinear oscillator with a non-symmetric potential
G. Litak, M. Ali, L. M. Saha
We examine a strange chaotic attractor and its unstable periodic orbits in case of one degree of freedom nonlinear oscillator with non symmetric potential. We propose an efficient…
Chaotic Vibration of a Quarter-Car Model Excited by the Road Surface Profile
Grzegorz Litak, Marek Borowiec, Michael I. Friswell +1
The Melnikov criterion is used to examine a global homoclinic bifurcation and transition to chaos in the case of a quarter car model excited kinematically by the road surface profi…
Suppression of chaos by weak resonant excitations in a nonlinear oscillator with a non-symmetric potential
Grzegorz Litak, Arkadiusz Syta, Marek Borowiec
We examine the Mielnikov criterion for transition to chaos in case of one degree of freedom nonlinear oscillator with non symmetric potential. This system subjected to an external…
A Numerical Study of a Simple Stochastic/Deterministic Model of Cycle-to-Cycle Combustion Fluctuations in Spark Ignition Engines
G. Litak, M. Wendeker, M. Krupa +1
We examine a simple, fuel-air, model of combustion in a spark ignition (si) engine with indirect injection. In our two fluid model, variations of fuel mass burned in cycle sequence…
Dynamics of a Gear System with Faults in Meshing Stiffness
Grzegorz Litak, Michael I. Friswell
Gear box dynamics is characterised by a periodically changing stiffness. In real gear systems, a backlash also exists that can lead to a loss in contact between the teeth. Due to t…
Estimation of a Noise Level Using Coarse-Grained Entropy of Experimental Time Series of Internal Pressure in a Combustion Engine
Grzegorz Litak, Rodolfo Taccani, Krzysztof Urbanowicz +3
We report our results on non-periodic experimental time series of pressure in a single cylinder spark ignition engine. The experiments were performed for different levels of loadin…
Cycle-to-Cycle Fluctuations of Burned Fuel Mass in Spark Ignition Combustion Engines
M. Wendeker, G. Litak, M. Krupa
We examine a simple, fuel-air, model of combustion in spark ignition (si) engine with indirect injection. In our two fluid model, variations of fuel mass burned in cycle sequences…
Combustion Process in a Spark Ignition Engine: Dynamics and Noise Level Estimation
T. Kaminski, M. Wendeker, K. Urbanowicz +1
We analyse the experimental time series of internal pressure in a four cylinder spark ignition engine. In our experiment, performed for different spark advance angles, apart from u…
Nonlinear Vibration in Gear Systems
Grzegorz Litak, Michael I. Friswell
Gear box dynamics is characterised by a periodically changing stiffness and a backlash which can lead to a loss of the contact between the teeth. Due to backlash, the gear system h…
Nonperiodic Oscillations of Pressure in a Spark Ignition Engine
M. Wendeker, G. Litak, J. Czarnigowski +1
We report our results on non-periodic experimental time series of pressure in a spark ignition engine. The experiments were performed for a low rotational velocity of a crankshaft…
Chaotic Combustion in Spark Ignition Engines
M. Wendeker, J. Czarnigowski, G. Litak +1
We analyse the combustion process in a spark ignition engine using the experimental data of an internal pressure during the combustion process and show that the system can be drive…
Surface Quality of a Work Material Influence on Vibrations in a Cutting Process
J. Lipski, G. Litak, R. Rusinek +4
The problem of stability in the machining processes is an important task. It is strictly connected with the final quality of a product. In this paper we consider vibrations of a to…