Measurements of Microjet Cooling and Phase Change Characteristics Using Microcantilever Heaters

Abstract

This paper reports novel microcantilever metrology tools to investigate free microjets emanating from a micromachined nozzle having 10 μm diameter. Microcantilever sensors are well-suited to interrogate these flows due to their high spatial and temporal resolution. In this work, microcantilevers with integrated piezoresistors have been used to detect the breakup distance of free microjets, and microcantilevers with integrated resistive heaters have been applied to study microjet cooling and phase change characteristics. Measured microjet thrusts were in the range of 10 – 60 μN and heat fluxes were measured in the range of 25 – 350 °C. The convective heat fluxes by microjet impingement boiling were estimated at 2.9 – 7.6 kW/cm2. The techniques reported herein are promising to characterize microscale flows.

A New Non-Invasive Air-Based Actuator for Characterizing and Testing MEMS Devices

“…However, due to its importance in evaluating the performance of this software, it should be verified before any further attempts on other data from simulations. To do so, here we have chosen one of the most accurate models of beam modeling, namely Timoshenko beam theory with couple-stress theory, which considers the effect of micro-sizes in MCLs dimension and also the planar shear stress along the MCLs [53,54]. Therefore, the theory that was expanded through Equation (8) to Equation (21) is accurate enough for validating the results of COMSOL software.…”