Dr. David Chao and Dr. Nengli Zhang with the Multidimensional Contact Angle Measurement Device (MCAMD)
The Multidimensional Contact Angle Measurement Device (MCAMD) (John Sankovic, Nengli Zhang & David Chao) is providing critical contact angle data for several NASA space experiments including the Nucleate Pool Boiling eXperiment (NPBX) in the Boiling eXperiment Facility (BXF) and the Constrained Vapor Bubble (CVB) in the Fluids and Combustion Facility (FCF).
- The modified MCAMD further extends the capability for the contact angle measurement of liquid droplets to measurements on various surfaces. This enables measurements in heat transfer systems whereby heat is either being added or removed from the fluid to enable studies of evaporation and condensation such as rewetting phenomena in cryogenic propellant tanks in reduced gravity. It also permits measurements in real systems whereby the surface treatment may be nonuniform or contaminated and the liquid droplets may be tainted with impurities, such as in a proposed capillary-driven, air-urine separator for the advanced life support systems being developed for future space missions.
- The modified MCAMD can also be used for terrestrial applications such as the development of new adhesives and nanofluidic devices. Adhesives in dentistry made significant improvements when the importance of contact angle was recognized in spreading and bonding between the glues and the substrate materials. Liquid imbibition into nanofluidic devices is almost exclusively governed by wetting phenomena whereby the contact angle determines whether the liquid will penetrate into entry ports of the device. Such devices, such as the “lab on a chip” concept are also being investigated by NASA as a lightweight sensor technology.
- The MCAMD is a low cost alternative to existing devices for contact angle measurement that provides detailed contact line information around the entire perimeter of a liquid droplet under a wide variety of conditions. These existing devices are more limited to measurements of advancing and receding contact angles.
The technology can be used to improve the performance of paints, adhesives, and lubricants, as well as boiling heat transfer processes.
More Information
- Device for Instantly Measuring Contact Angles of a Liquid on a Solid Surface [External Link], Technology Transfer & Partership Office
- NASA Researchers Receive R&D 100 Awards [External Link] (October 2008, SpaceRef)
- NASA Glenn Featured Image: Award-Winning Invention [External Link]
