Vinod Srinivasan Receives NSF CAREER Award
ME Assistant Professor Vinod Srinivasan received an NSF Faculty Early Career Development Program (CAREER) Award for his work on heat transfer research. His project, "Universal Dynamics of Thermal Fluctuations in Pool Boiling and Their Role in Predicting Critical Heat Flux," will develop a new understanding of the boiling process. The CAREER Award is the NSF's most prestigious award in support of early career faculty who have the potential to serve as academic role models in research and education.
Boiling is a highly efficient heat transfer mechanism used in power plants, micro-electronics, and industrial heat exchangers. In recent years, microfabrication technology used for manufacturing electronics has been adapted to create extremely fine-scale roughness on boiling surfaces, tremendously enhancing their heat transfer performance. However, all surfaces are prone to contamination that can cause physical and chemical changes on the surface. Srinivasan's research will look at the phenomenon known as "critical heat flux," which causes the liquid above a surface undergoing boiling to disappear and get replaced by vapor, which instantaneously causes overheating and failure. This can lead to dramatic, unpredictable shifts in their performance, creating catastrophic nuclear accidents in reactors — the cause of which is currently unknown. This project will model and predict this phenomenon, even as the surface continuously degrades due to contamination and the safety margin is changing in unknown ways, by measuring temperature fluctuations on a surface and using these to show that they are multifractal in nature (i.e. repeating their patterns at multiple time and length scales). This in turn implies that any theory that seeks to predict critical heat flux needs to incorporate interactions between bubbles. The project will gather information on these interactions.
Srinivasan's study will develop a new framework for understanding the boiling process that enables assessment of the safety margin in real time, even as the surface degrades. Besides improving safety, this may promote adoption of more advanced heat transfer enhancement techniques, while providing a better fundamental understanding of the boiling phenomenon. This understanding will lead to increased adoption of high performance surfaces in heat exchangers, which have not been adopted because it is not clear how they will fare in the long term. This means increased energy efficiency, safer thermal power plants, and electric batteries and fuel cells. It also may enable the design of more powerful electronics chips, since liquid cooling becomes more safe and reliable.
As part of the project, an exhibit appropriate for middle schoolers will be developed jointly with the Bell Museum of Minnesota, to illustrate chaotic phenomena such as the "butterfly effect," which has certain parallels with the chaotic boiling process. The PI will also develop modules for outreach activities that bring middle school girls to campus for STEM-oriented workshops.
This work will be done with PhD student and MTPL member Ankit Saini.