Rohit Velankar, a senior at Fox Chapel Area High School, stumbled upon a thought-provoking question while engaging in a simple, everyday act: pouring juice. The rhythmic “glug, glug, glug” sound that emerged as juice flowed from the carton led him to ponder the physics behind it. Specifically, he wondered whether the material elasticity of the container influenced the fluid’s drainage characteristics. Initially intended as a straightforward inquiry for a science fair project, this curiosity evolved into a collaborative scientific endeavor with his father, Sachin Velankar, a chemical and petroleum engineering professor at the University of Pittsburgh Swanson School of Engineering.
The project propelled the Velankar’s into an unexpected research journey. Once they established their shared interest in investigating fluid dynamics, they transformed a section of their basement into a makeshift laboratory. This collaboration between father and son not only strengthened their familial bond but also added an intriguing dimension of mentorship and shared inquiry into the realm of scientific exploration. The culmination of their research efforts was the publication of their findings in the esteemed journal, Physics of Fluids.
The research undertaken by the Velankars delved deeper into the phenomenon known as glugging—the intermittent bursts of sound produced when a liquid exits a container. Their experiments revealed a significant difference in the draining speeds of containers; specifically, deli containers with rubber lids tended to empty at a faster rate than those equipped with plastic lids. Rohit identified a correlation between the container’s flexibility and the glugging effect, arguing that the elastic characteristic helps stabilize pressure, allowing the liquid to exit with less resistance.
Sachin Velankar expanded on this idea, explaining, “The glugging sound arises because the departing liquid generates a pressure decrease within the container.” This insight led them to realize that the flexibility of various containers, including IV fluid bags and boxed wine, might facilitate a smoother drainage process and minimize glugging.
Armed with determination and creativity, the Velankars crafted their own custom acrylic bottles with rubber lids using tools available in their school’s makerspace. They ingeniously incorporated a pressure sensor at the base of each bottle, allowing them to measure the pressure fluctuations correlated with each glug. By manipulating the diameter of the bottle’s opening, they simulated varying degrees of flexibility, ultimately confirming that containers with higher elasticity drained more efficiently but produced larger, less frequent glugs.
In addition to their intriguing findings, the father-son duo emphasized the importance of combining practical experimentation with theoretical understanding in the field of fluid dynamics. Their research highlights how everyday experiences can serve as the foundation for scientific exploration, encouraging other young scientists to pursue their inquiries with passion and inquiry.
Rohit Velankar’s initial question about the physics of pouring juice evolved into a valuable scientific exploration that merged family dynamics with intellectual curiosity. Their published paper stands not only as a testament to their hard work but also as an inspiring narrative that highlights the intersection of education, family, and science. This unique journey underscores the idea that significant discoveries can originate from the simplest moments, proving that curiosity, when combined with collaboration, can yield remarkable insights. In a world increasingly driven by scientific innovation, the Velankars’ story exemplifies the enduring importance of fostering inquisitive minds and working together to unravel the complexities of our universe.