EAGER: Particle Concentration Measurements in Turbulent Flows using Magnetic Resonance Imaging

Stanford University, Stanford CA

Investigators

Abstract

The behavior of small solid particles such as sand, dust or volcanic ash moving in water or air flows is an important consideration in a wide range of fields. For example, environmental dust can shorten a jet engine's service life by 90 percent. State-of-the-art experiments can only collect particle data in highly simplified systems. A new technique is being developed that uses conventional medical Magnetic Resonance Imaging systems to make quantitative measurements of how particles are distributed in complex systems. The data sets produced would have broad benefits for engineers, as well as for researchers studying environmental, biological, and fundamental physical systems. A series of validation experiments will be carried out to complete development of the imaging technique and to establish its accuracy and limitations. After the technique has been developed, two additional experiments will be performed to demonstrate broad societal benefits of the new measurements: one by assisting the design of more dust-resistant aircraft engines and the other by illuminating how inhaled dust or spray droplets move through the human nose. Following the successful completion of this project, researchers would have a general method to aid in their understanding of any system where particles are carried by air or water currents. Preliminary experiments have demonstrated that Magnetic Resonance Imaging can be used to measure the concentration of microparticles quantitatively and in three dimensions. The proposed work begins with a detailed set of validation experiments to test the range, resolution, and accuracy of the new experimental method across a range of flow conditions and particle concentrations. Following the validation experiments, two application-relevant test cases will be employed as test beds for continued development of the technique. The first will explore the behavior of particles in an internal impingement cooling geometry frequently employed in aircraft turbine engine cooling systems. In the second test case, particle concentration will be measured inside a model human nasal passage. In addition to developing the technique, the test cases allow for new understanding of particle transport in two disparate fields of significant research interest. The impact of the project has the potential to extend well past the scope of this proposal, as the technique could prove useful for computational model validation, fundamental particle-laden flow research, or a number of other research areas.