Weeks Nine & Ten

These past ten weeks have gone by so much faster than I expected, but I did get a lot done on my project in that time. After spending quite a while trying to improve our error calibration procedure (since without accurate calibrations, we have no way of judging how trustworthy our data is), we've obtained some useful results with our textured surfaces. The symmetric depth texture reduced the apparent viscosity of our most viscous fluid by 20.7%, while the linear slope depth textured gave a 6.49% reduction. Both textures also produced significantly higher normal forces than our flat plate control, with the linear slope depth texture producing the most. These results are important because stress reduction and force production are both key factors in improved lubrication, as stress reduction (or friction reduction, really) will lower the amount of energy required to move sliding machine surfaces, and increased normal force will push apparent adjacent surfaces to prevent wear and tear on machine parts.

These past few weeks, I've shifted my focus away from Newtonian oils and done some preliminary work with non-Newtonian fluids, since our ultimate goal is to be able to co-design both the surface and the fluid in order to improve lubrication even more. Our non-Newtonian results have been promising; the stress reductions seem to show the same pattern as the Newtonian fluids did, with the symmetric depth texture causing significantly more of a drop than the linear slope depth. The normal force data is a little less clear right now, as while the fluids have been producing forces even with the flat plate, the difference in force production between the flat plate and the textured plates seems largely negligible. We haven't done any repeat testing yet, however, so this may clear up more when we are able to go back and do multiple trials on the same fluid.

Overall, I'm leaving this project feeling pretty good about the progress we've made, though there's still much more to explore and I'm interested to see what direction it takes after I leave. This experience has taught me not just about fluid power and, more specifically to my project, rheology, but also about the pros and cons of full-time lab work and what I might expect if I choose to go to grad school a few years from now. I think what I have enjoyed most has been the freedom to take the research in any direction we want, while also having the constant guidance of a faculty member much more knowledgeable and experienced than I to steer and develop our thoughts. I've learned a lot from my advisor and lab group members alike, and I believe I'm going back to school with a better grasp on what to expect from my future in science and engineering.

I'm presenting to my lab group during our meeting this Friday (wish me luck!), but I've attached a photo of the poster I laid out for this project so you all can peruse it. It's been great reading your blogs this summer and getting to see my project as part of the greater narrative of fluid power that all of our work combined creates. I hope you've all had fantastic summers and have even better school years to look forward to, and thanks so much to Alyssa for putting so much into this experience and making it so worthwhile.

Best of luck with your last few days of work, and please keep in touch!

Nikita