Gas-evolution oscillators. 10. A model based on a delay equation

We have developed a general model for a gas-evolution oscillator with the use of two differential delay equations in two unknowns denoting the population of dissolved molecules in a solution and the pressure in the gas phase. In addition to two measurable rate constants, the only disposable parameter is a delay time which relates to the time before the present at which nucleation occurred. Previous modeling efforts used over 60 ordinary differential equations with as many variables denoting populations of different sizes of bubbles. Our very simple approximate equations model a wide range of experimental situations much better than there would seem to be any reason to expect.