Clearing the air

Jan 6, 2006

A research contract between Kettering University and a federal contracting corporation provides new details on the dispersion of chemicals, offers insight into the absorption of these elements into our environment and provides new employment opportunities for students and research professionals.

It's inescapable: our world is made up of complex chemical compounds, some of which occur naturally in our environment while others are created by human hands.

But what happens to these elements when they are manipulated for dangerous purposes and become absorbed into the earth? Can we predict how long these chemical agents will remain dangerous following, say, a chemical attack?

It's a difficult subject for the general public to address, but part of our national reality since the 9/11 attacks. The answers to these questions might come from Kettering's team of experts under the direction of Dr. Homayun Navaz, professor of Mechanical Engineering, who also serves as the primary investigator in the Chemical Agent Fate Research Program, a $2.9 million research contract given to the University by a federal contracting corporation. Years ago, the short answer to these questions was difficult to formulate. Today, the answers are still a bit complex but at least they provide important new clues regarding how to predict the lifecycle of chemicals in our environment, particularly in soil, and how our world can rid our environment of these elements.

But when most readers see the words chemical and attack in the same sentence, their chest muscles suddenly clench and thoughts about potential chemical terrorism race through their minds. And while this project does indeed investigate the fate of chemical elements in attacks using such agents, the scope of this endeavor reaches into other important parts of our global society and could exert an important influence on the use of pesticides and other chemicals in such areas as agriculture and farming.

For Navaz, the reasons for conducting this work are simple: "If terrorists obtain chemical agents for use in some form of an attack, they will not be shy about using them," he said, pointing to the heart of why this research is so important. "We must be more conscious of the magnitude of a terrorist's desire. As the news shows each night, they are unafraid of exerting their will. This is why we must come to some scientific understanding of the impact of these agents before they could be used," he added.

Kettering won this contract to develop computer models that predict how long chemical compounds remain active in the environment following use during an attack. This mathematical analysis, which Dr. Navaz will direct, examines actual data taken at five testing sites from around the world. The goal is to protect life by converting highly technical science and experiential mathematical modeling information into what Navaz characterized as a "usable tool for soldiers and the general population. " The computer models will enable military forces to better protect themselves and operate in contaminated environments because simulations will depict the movement and absorption of elements into the surrounding environment.

Navaz's research relies on several computer modules coupled together to describe the distribution of a chemical agent within an environment. For example, the evaporation module predicts the rate at which a vaporized agent enters the air. Another model tackles the transportation, chemical reaction and evaporation of an agent within a porous substrate, such as concrete. These two modules are then coupled to a transport module that contains wind and its turbulence characteristics to simulate the movement of these elements within the environment. The overall objective is to create a viable mathematical simulation tool that

  • predicts the fate of a chemical agent after it is deposited on the ground;
  • is based on an experimental and analytical hybrid approach; and
  • provides an engineering tool to present temporal and spatial information about an agent's fate.

But like most chemical research analysis of this nature, one must find suitable areas to test hypothesis developed by computer simulated models as a means of verifying these simulations. Navaz conceded that due to the political and societal impact of this project and the threat of chemical terrorism, the general public would be a bit nervous to hear of this project. However, this is not a project geared to create fear. Rather, the idea is to study chemical agent fates and determine how we can best negate the impact of these elements if and when they are dispersed. After all, knowledge is critical. Developing a strategy to understand and manage the potential release of a chemical agent is necessary.

"Other countries have indicated a desire to share their testing results in their parts of the world as long as we share our computer simulation results," Navaz said. "For example, countries such as the Czech Republic, the Netherlands and South Africa are already conducting tests on the fate of chemical agents for several reasons: first, these countries have serious concerns about chemical terrorism and thus provide research funding to study this subject; second, many of these countries have dedicated facilities fully equipped to investigate these chemical agents and their absorption and movement; and third, because the population densities of these countries are so low, there would be no impact on human life with testing conducted in natural environments far from human habitats."

None of the testing will take place in Flint or at any Michigan locations, he said, adding that most people "would express fear that we might conduct testing in areas where there are people in close proximity. In fact, tests take place far from human life and sites were carefully chosen based on this fact." Countries will share test results with Navaz, which he can then use to plug into his model.

This project also has significant ramifications on how pesticides and other chemicals used for agricultural purposes affect our environment. The computer modeling and simulation of chemical dispersion and dissipation, for example, can show how elements used in pesticides might leech into underground water sources and soil, and infiltrate air under a variety of environmental conditions. "This modeling is applicable to really anything that deals with motion underground," Navaz noted. "Oil, chemicals, gases-all one needs to do is change the properties of these elements, plug them into the modules and calculations, and engage the simulation."

Results thus far are positive, he explained. Before this project began, there was no effort to conduct comprehensive modeling of a chemical agent's fate, which makes this research project so original and important. To date, Navaz and his project partners have established the evaporation of a liquid agent to wind condition and have validated this model with experimental data taken in a controlled wind tunnel facility. Another important aspect to both evaporation and transport of an agent in vapor form is the wind tunnel model. "Caltech is in the process of wind modeling and so far that has proven that the turbulence intensity of the wind does affect the evaporation rate of an agent," he said. This effect, he noted, could range from 2-25 percent depending on the intensity of wind turbulence.

The project has also generated a number of opportunities for the University in several respects. As previously noted, Navaz has partnered with several institutions to conduct various module simulations, including Caltech, which will utilize their massive wind tunnel for the transport modeling associated with measuring air-born chemical elements in wind. Second, the University has a dedicated office space in downtown Flint for various activities, including work for several Kettering co-op students and graduate students. Third, with Michigan's unemployment above 6 percent (compared to 5 percent nationally) according to the October 2005 report published by, companies continue to express hesitation about establishing businesses and offices in the state given the uncertainty of the automotive industry. But this sort of project falls directly in line with Gov. Granholm's vision to re-establish the state as a technological leader and to create workforce development opportunities in fields other than automotive. Navaz hopes that the future holds other research opportunities such as this to help re-establish the state as a place where companies can engage in business activities.

Written by Gary J. Erwin
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