Experimental Study and Analysis of Dropwise Condensation Using Quartz Crystal Microbalance

Abstract

This work reports a novel Quartz Crystal Microbalance (QCM) based method to analyze the droplet-micropillar surface interaction quantitatively during dropwise condensation. A combined nanoimprinting lithography and chemical surface treatment approach was utilized to directly fabricate the micropillar based superhydrophobic surface on the QCM substrate. The normalized frequency shift of the QCM device and the microscopic observation of the corresponding nucleation, drop growth, and drop coalescence processes clearly demonstrate the different characteristics of these condensation states. In addition, a synchrosqueezed wavelet spectrum based multi-resolution technique was utilized to analyze the resonant signal from the QCM sensor in both time and frequency domains simultaneously. An integrated discrete system modeling along with a hybrid signal and image processing approach was adopted to identify the response of the micropillars under different stages of dropwise condensation (DWC). The outcome of this signal processing research leads to a fundamental understanding of DWC spanning multiple time and length scales. The proposed study will also contribute to an in-depth understanding of different hydrophobic surfaces and DWC through this advanced signal processing and surface treatment. The developed QCM system provides a valuable tool for the dynamic characterization of different condensation processes.

Development of a Flow Injection Based High Frequency Dual Channel Quartz Crystal Microbalance

“…There has been a long history for quartz crystal microbalance (QCM) resonators to serve as a mass-frequency transducer, which vibrates in a thickness shear mode (TSM) mode. Own to its high sensitivity, stability, simple structure and low cost, QCMs has been widely applied in bio- or chemical sensing field [ 1 , 2 , 3 , 4 ]. Usually, the QCM resonator is composed of an ATcut quartz crystal piece and two metal film electrodes coated onto double surfaces of the quartz crystal chip.…”

Evaluating Superhydrophobic Surfaces under External Pressures using Quartz Crystal Microbalance

“…Su et al developed the QCM technique to study the liquid/solid interaction during dropwise condensation on flat and micropillar structures with different hydrophobicities. His results demonstrated the capability of the QCM to analyze the dynamic of the condensation process in comparison to the optical imaging technique. − Wang et al used a QCM to characterize the liquid penetration on a micropillar pillar structure with superhydrophobic state and the QCM response was quantified numerically and experimentally. Their experimental results showed that the meniscus pendant depth of liquid using the QCM were in good agreement with results obtained from cryogenically focused ion beam/scanning electron microscope (cryo FIB-SEM) .…”

Study on Dual Channel Lateral Field Excitation Quartz Crystal Microbalance for Measuring Liquid Electrical Properties

“…QCM is a well-known high precision resonator with a measurement accuracy in the nano-gram range. The sensor has a high sensitivity, simple structure, and can be used in real time without interruption in gas or liquid environments [ 1 , 2 , 3 ].…”