"Café des Sciences" January 20th 2010
Speaker : Guillaume Blanquart, Ph.D.
Title : "Old and new concepts : the challenges of combustion"
Subject : the interactions between combustion and turbulent air flows
This first edition of the "Café des Sciences" took place on Wednesay, January 20th 2010 at the Consulate General of France in Los Angeles. Guillaume Blanquart, who graduated from the French "Grande Ecole d’Ingénieur" Polytechnique in 2002 in Applied Mathematics, got both his M.Sc. in Aeronautics and Astronautics and his Ph.D in Mechanical Engineering from Standford University, respectively in 2004 and 2008. He followed with a one-year post-doctoral study at Standford before joining the California Institute of Technology as Assistant Professor in Mechanical Engineering.
Guillaume Blanquart gave a presented his research work and its perspectives and potential applications to an audience of 12 people. In order to stress the large time and space scales of this phenomenon, Pr. Blanquart gave several examples such as internal combustion motors, the dynamics of fires or the thermal protection of space shuttles. Prerequisites in chemistry, flow physics, mechanics and thermal physics demonstrate the pluridisciplinarity of this field of studies.
Pr. Blanquart then presented two engine models. The first one is used in car motors, uses fossil fuels and oxygen to produce energy. This model has proven to be reliable and sturdy but the incomplete combustion of the fuel provokes the formation of carbon-rich pollutants : soot. Computer models make it possible to study the influences that the homogeneity of the fuel-oxygen mix -which is function of the flows in the combustion chamber - and the combustion have on each other. It is thus possible to try and understand and improve the way this complex system works.
The second model is the hydrogen fuel cell whose main advantage is the absence of carbonated fuels, leading to no soot production. However, the very small size of the hydrogen molecule is the cause of many unexplained instability problems that can lead to a sudden and unexpected halt of the combustion process in the engine. It is also harder to accurately model this type of engine and no satisfactory predictive computer model has been devised yet. Devising such a computer model is one of Pr. Blanquart’s research topics.
Other topics were tackled during this presentation and the discussions that followed, such as the management of energy -combustion amounts to 85% of energy production today, what are the alternatives to fossil fuels and how viable are they? - health - what is the impact of sooth on human health? What are the best strategies to reduce it? - economy -is it economically possible to implement new propulsion technologies ? - thus showing the vast and sometimes unexpected perspectives opened by scientific fundamental research in our daily lives.