Simulation model and droplet ejection performance of a thermal-bubble microejector

The present study investigates simulation model and droplet ejection performance of a thermal-bubble microejector. This model is achieved by coupling an electric-thermal model and flow model with bubble dynamics equations. We simulate the bubble nucleation and the bubble growth, to predict the droplet ejection process. The model is validated by comparing prediction results with experimental data. Especially, in forming one droplet, the results show that the ejection volume increases linearly with the thermal energy, and the variation range of the pulse width is within ∼0.2 μs. Moreover, the effects of the geometry of the nozzle, reservoir and thin-film resistance, applied current and pulse width on satellite droplets creation, droplet speed and volume are presented.