One-Dimensional Model of Bubble Growth and Liquid Flow in Bubble Jet Printers

Abstract

The model is based on a one-dimensional heat conduction equation, an equilibrium pressure-temperature relation, energy and mass conservation relations and a hydraulic equation. Numerical results showed a good agreement with an experiment under typical operating conditions of a bubble jet printer with water-based ink. The bubble-generation temperature was estimated to be ∼270°C, which is close to the experimentally obtained superheat limit of water. The initial bubble pressure was estimated to be ∼4.5 MPa, but it decreases to less than ∼10 kPa in 10 µs. This rapid decrease of pressure explains the cavitational action of the bubble, observed in actual bubble jet operations. Effects of ink viscosity, nozzle outlet length and operating voltage were investigated using the model. The results provide a basic guide to the design of bubble jet printers.