I am working with Jean St Pierre here, who I had worked with before for many years on a joint project on fuel cell modelling. He was working for Ballard Power Systems in Vancouver at that time. This was a "golden period" of my career when there was a larger group of us working on this project. We had funding from the government (through the MITACS NCE) and matching funds from Ballard for the research. Most of the money was used to pay the graduate students and post-doctoral fellows that made up the larger group. More importantly, we had a strong connection with the experimental scientists at Ballard, including Jean, who directed us to the interesting application questions and did the experiments both to fit parameters in the models we developed and to validate them afterwards. This was a very fun project. I enjoyed working on these problems in that group and I think we did some things that were quite useful to the industry.
There is a specific new project that Jean brought me out here to work on - doing some modelling work on the scavenging effect of liquid water on contaminants in fuel cells. Maybe I should say something about what I mean by "modelling". This is the process by which physical processes are described (approximately) by mathematical equations. These equations usually can't be solved exactly but are approximated using numerical methods on a computer. The mathematics of this approximation step is my original research area, called Numerical Analysis. If this whole process is done well enough, you can get insight into an engineering problem using the computer simulations. An example is the aeronautical industry that uses simulation tools to design new aircraft. There are approximations involved, so the simulations won't necessarily predict how a device will actually behave. However, the simulations are easy, quick, cheap (I mean, inexpensive), and safe. Thus, any insight you can get into an engineering design process using simulations of mathematical models can save a lot of time and money.
So this new project involves modelling the scavenging effect of liquid water on contaminants. The literature I have read concerns this process not in fuel cells but in the atmosphere. The papers I have looked at consider rain drops falling through air with contaminants (Sulphur di-oxide for example). Now, the drops don't just pick up SO2 under them as they fall through the air. Rather, they absorb SO2 and cause a concentration gradient in the air around the droplet that draws in more SO2 from the surrounding volume. Thus, a stream of drops mapping out a fairly small volume as they fall can deplete a much larger volume of air of SO2. This scavenging effect has some chemical engineering uses. In the atmosphere, while it seems great that droplets can clean up the air, the SO2 the drops pick up can be converted chemically into sulphuric acid, leading to the phenomenon of acid rain. So, I am looking at the scavenging effect of liquid water, which is usually present in the kind of fuel cells I have worked on (Polymer Electrolyte Fuel Cells), on contaminants that can be found in the inlet gases to these cells. Many of the mechanisms are the same as the atmospheric case, but the length and time scales are different and this may change what the dominant or rate-limiting effects are.
I also hope to finally write up as a journal article an old fuel cell project with Jean and Keith Promislow that we began many years ago. This article is long overdue.
These will be fun projects but I am a Canadian in Hawaii in February! I have never been here before and have some tourist activities planned for weekends. This first weekend I took the bus to the Farmer's Market at Kapiolani Community College, right across from Diamond Head. OK, this may not seem like a top priority tourist thing to do, but I like exploring local food.
On Sunday, Jean and his wife, Andrea, took me hiking up on Diamond Head, the crater of an extinct volcano. There is a trail up to the rim from which there are fantastic views of Waikiki and the ocean.
From there we went on to the Foster Botanical Garden, with some great plants and trees, some of whom had small friends.
No comments:
Post a Comment