Q&A with Assistant Professor Sayan Biswas

1.  Where are you from originally, and where were you living before you moved to Minnesota?

I was born and grew up in a small town in eastern India named Raniganj. Raniganj, located on the bank of river Damodar, is known for its coal mines that produce one the best quality of non-coking coal in India, with average ash content of less than 20%.

I lived most years of my life in university towns. After finishing high school in Raniganj, I moved to Kolkata for my undergraduate engineering degree. In 2010, I arrived in the U.S. Since then, I have lived in Storrs, Connecticut, West Lafayette, Indiana, and most recently in Livermore, California, before moving to Minnesota.

2. What class/experience/person inspired you to become a mechanical engineer?

From a young age, I was captivated by mathematical equations that could precisely describe the physical world. Our understanding of the physical world lets us design new devices and tools that never existed before. I was fascinated by engineering innovations that create positive impacts on society, culture, and economy. In addition to that, I was an avid reader of science-fiction stories. Isaac Asimov, H. G. Wells, Jules Verne, Arthur Clarke, George Orwell tremendously influenced my thoughts during my teenage years. As Arthur Clarke writes, “Any sufficiently advanced technology is indistinguishable from magic.” I wanted to learn that “magic” to create advanced tools and devices for solving practical, relevant problems. Mechanical engineering offered a wide variety of topics ranging from energy to mechanics to robotics that attracted me. I realized, from ball pen to battery, television to telescope – mechanical engineering is indispensable. The breadth and depth of the discipline inspired me to pursue mechanical engineering.

3. What do you like most about teaching?

I find teaching enjoyable and incredibly rewarding. I feel energized after an engaging teaching session. I get immense satisfaction when a student understands a difficult concept or learns how to solve a problem. I like watching the students grow and evolve through the coursework and eventually succeed in their life. However, the aspect of teaching I love most is the questions from the students. Questions, discussions, arguments, and skepticism are the backbones of the scientific learning process. Questions from students help me understand how the students think, compel me to think and provide an alternate explanation, and broaden my perspective. It also helps modify my teaching methods and strategies. As an instructor, teaching is a learning experience. When students start asking questions, it indicates that my teaching has successfully evoked their interest and curiosity.

4. What are your favorite places in the Twin Cities that you’ve discovered so far?

Due to COVID, my wife and I are trying to restrict our indoor activities and avoid crowded outdoor places. Things we love like theatre and museums we could not visit. So far, I have seen only a few places in the Twin Cities. Among them, I enjoyed the sculptures in the Minneapolis Sculpture Garden. On a relatively warmer day, I had a pleasant time strolling on the West River Parkway trail. I love public libraries. The nearest library is Arvonne Fraser Library that is 7 mins walking from where I live. I relished the Korean food joints in Dinkytown. I am eagerly waiting for the spring to explore the University campus and Twin Cities.

5. How are you adjusting to the temperatures in Minnesota over the winter?

I mostly over-dress. Except for the eyes, I wrap myself with multiple warm layers, especially around the head and neck. I have received dressing compliments from fellow Minnesotans in parks and grocery stores. Even though I have experienced Connecticut and Indiana winters, inarguably, Minnesota winter is colder! So, I invested well in good winter clothing and shoes. Depending on the weather, I try to go out for at least 10 mins every day to get acclimatized to cold temperatures. I talk to my colleagues on Friday at Zoom coffee hour about their winter experience. I am embracing Minnesota winter with simple outdoor activities. Last week I visited the Ice Maze in Stillwater and immensely enjoyed the Ice Slide there!

6. What is your proudest moment as an engineer?

During my postdoctoral research at Sandia National Laboratories, I aimed to develop a fully functional low-temperature plasma igniter for automotive and energy applications. Low-temperature plasmas have been extensively studied at low-pressures – sub-atmospheric, a few Torr to atmospheric pressure. However, plasma behavior at higher pressures is still an enigma. Even the lower operating range of my engine was 20-40 times the atmospheric pressure, and without much fundamental understanding of low-temperature plasma at elevated pressures, it was not easy to design a working plasma igniter. I created many different igniter designs during the development phase and damaged all these igniters running at high-pressure.

Nonetheless, I kept trying. My lab at Sandia has optical engines that let me “see” the gas exchange and combustion processes inside the engine. But any optical and laser measurements were extremely challenging at high-pressure, reacting conditions. I set up a high-speed radical imaging system to capture the plasma discharge and subsequent ignition processes.

One day, I tested a variant of plasma igniters – a four-prong flower-petal geometry that produced corona-type streamers inside the power cylinder. Surprisingly, the engine operation became stable with a few points increase in thermal efficiencies compared to the baseline spark ignition. I kept on moving towards challenging operating regimes, and yet, the engine ran remarkably well. After so many failures and setbacks, I was delighted to find a working plasma igniter prototype. But the next moment, I asked myself – why did it work? The next several months, I spent time in the lab running more experiments and carrying out high-speed imaging, trying to understand the fundamental physics. Combing the optical imaging with other sensory measurements, I realized how the stochastic plasma streamers could create multiple ignition pathways enhancing the fuel chemistry. When I figured out the underlying physics, I was even more satisfied as an engineer and researcher. At the University of Minnesota, with a team of talented and driven undergraduate and graduate students, I am excited to explore cutting-edge engineering and scientific problems related to plasma, power, and propulsion.