Visco's recent research results were impressive enough to earn him Tennessee Technological University's 2000 Kinslow Engineering Research Award for a paper that appeared in the prestigious Journal of Chemical Physics.
"His work is 'cutting edge' research," said Marie Ventrice, TTU's associate dean of engineering for graduate studies and research. "The paper is a significant contribution to chemical engineering science and exemplifies research innovation."
Visco, a chemical engineering assistant professor, admits his research niche is difficult to explain even to colleagues at times, but his work with the interaction of molecules can improve the way chemical engineers design equipment, control yields, reduce pollution and increase profits.
It's essential for chemical companies to know how to handle associating fluids, fluids like water in which molecules of the same kind form complex structures. These structures are so complex it is difficult to predict how fluids will interact in different quantities and at different temperatures.
"What we've developed is a rule of thumb for other researchers to use when working with associating systems to save them time and increase the accuracy of the results they report," said Visco.
Before chemical engineers can make plant design decisions -- how tall or wide to design expensive equipment, for example -- they must know the thermodynamic properties of associating fluids at different variables. If they can't make accurate predictions, they can waste a lot of time and money on redesign. Accurate predictions also are essential to maximizing production and reducing pollution.
One way is to test each fluid over and over again at different temperatures, in different amounts -- but that could lead to hundreds or even thousands of expensive, time-consuming experiments. On the other hand, Visco's molecular simulation allows for these experiments to be performed on a computer, saving both time and money. These simulation results then are used to predict the thermodynamic properties used in order to estimate the size of plant equipment during the design phase.
Visco's work refines the process researchers have been using; they often depend on computer simulations that can have inherent flaws in predicting how associating fluids will act over a long period of time.
"It's easy to 'push the button' and assume computer calculations are correct," said Visco. "The research I'm working on is part of creating an awareness in the field of molecular simulation. After all, if you use anything -- an equation, a correlation, a theory -- and are not verifying the assumptions they're based on, how much confidence can you have in the results you report?"
Some simulations of strongly-associating systems may take days, months, even years to validate the basic assumptions on which the calculations are based, and it's hard to tell when they've reached that point. Visco's work will give other researchers a guide to estimating how long they need to run their simulations in order to achieve reliable results.The Kinslow Award is given annually for the best paper written by a TTU engineering faculty member and published in a refereed professional journal. The award honors Professor Emeritus Ray Kinslow, who taught for 32 years at Tennessee Tech and served as head of the engineering science and mechanics department for 25 years.