Impulsively Generated Incompressible Two-Phase Flow and the Asai Thermal Ink-jet Model

George Drummond Mcbain (1) , S G Mallinson (1, 2)

1 Memjet Australia Pty Ltd
2 School of Mechanical and Manufacturing Engineering [Sydney]

A widespread model of thermal ink-jet actuation prescribes the pressure of the expanding bubble as a rapidly decreasing function of time, this being taken as a finite version of a Dirac impulse with only the integral with respect to time mattering. Here it is shown that the impulse is actually easier to treat numerically than the bounded approximation and an implementation in OpenFOAM is described; however, solutions so obtained reveal that the flow does depend on the timescale over which the pressure is applied, i.e. on first and higher moments of the pressure function. An asymptotic expansion of a lumped linear model is derived which predicts the dependence of the induced flow on these moments for an arbitrarily shaped pressure pulse.

Domaines: Micro et nanotechnologies/Microélectronique; Mécanique des fluides [physics.class-ph]; Equations aux dérivées partielles [math.AP]; Systèmes dynamiques [math.DS]

George Drummond Mcbain, S G Mallinson. Impulsively Generated Incompressible Two-Phase Flow and the Asai Thermal Ink-jet Model. 21st Australasian Fluid Mechanics Conference, Dec 2018, Adelaide, Australia. ⟨hal-02050201⟩