Resonant Behavior in a Periodically Forced Nonisothermal Oregonator

Area of Science:

• Chemical Kinetics
• Nonlinear Dynamics
• Physical Chemistry

Background:

• Chemical oscillations are typically studied under isothermal conditions.
• Nonisothermal oscillatory systems offer complex nonlinear dynamic behaviors due to coupled heat generation and removal.
• The Oregonator model is a well-established framework for studying chemical oscillations.

Purpose of the Study:

• To investigate the dynamic behavior of a nonisothermal chemical oscillator by incorporating temperature as a variable.
• To explore the effects of external forcing, specifically coolant temperature and infrared irradiation, on the system's oscillations.
• To determine if external heat sources can induce resonant behavior and Hopf bifurcations.

Main Methods:

• The three-variable Oregonator model was adapted to include temperature as a dynamic variable, incorporating an energy balance equation.
• Temperature-dependent reaction rates were modeled using the Arrhenius law.
• Numerical simulations and parametric studies were performed under externally forced conditions (coolant temperature and infrared irradiation).

Main Results:

• The nonisothermal Oregonator model demonstrated complex nonlinear dynamic behavior.
• External forcing, particularly infrared irradiation, was found to induce resonant behavior and oscillations.
• The system exhibited a Hopf bifurcation under resonant conditions when subjected to external heat input.

Conclusions:

• Nonisothermal chemical oscillators are capable of rich dynamic behaviors not observed under isothermal conditions.
• External heat sources can be effectively utilized to control and induce specific dynamic phenomena, such as Hopf bifurcations, in chemical oscillators.
• The findings suggest potential applications in controlling experimental Belousov-Zhabotinsky reactors using infrared irradiation.