Julia Kornfield developed a is the polymer additives in jet fuel, the polymer molecules can each end covered with like Velcro can bond unit, form the "giant supramolecular", can effectively reduce the destruction of the fuel exploded, improve the safety of the flight performance.
By two pictures show the pilot flame after the impact jet fuel atomization extension (color scale shows the flame with the time extension). Above is to add the traditional long polymers, below to add the Caltech research and development of new type polymer, all the samples are 50 times in advance through the fuel pump. Long lost utility polymer, resulting in large hot ball of fire. Caltech polymer, however, still can reduce the impact of the degree of fire spread. Caltech polymer chain is not broken, but in each other through the pump out, after assembly into huge supramolecular again.
Before starting a intercontinental travel, jet plane filled with hundreds of thousands of gallons of fuel. In collision accident, so a lot of fuel for blast is very serious damage. Researchers at Caltech and JPL hair and clear as fuel additive, a kind of polymer can reduce accidents and terrorist attacks in the strength of the blast effect. At the same time, preliminary studies show that the additive when these benefits are not bad influences on the fuel performance.
Jet engines will compress air and mixed with fuel spray. An electric spark ignites a mixture of air and fuel caused by pushing forward plane controlled explosion. A jet plane is provided by thousands of such micro explosion driving force. However, atomization process (scatter fuel into spray to facilitate the process of light) is also contributing to the fuel in the crash spread quickly and easily burned.
Julia Kornfield developed this additive is a kind of polymer (made up of many repeating units of long chain molecules, also known as polymer materials), its each end covered with can like Velcro bonding of the unit. A single polymer molecules (long-chain molecules) spontaneously connection form of long chain called "giant supramolecular".
Giant supramolecular has unprecedented comprehensive performance, which makes it can control the fuel atomization process, improve the fuel liquid in the pipeline, and reduce the soot formation. Giant supramolecular can inhibit the crash in the atomization of fuel at the same time allow the atomization of fuel injected into the engine.
Other polymers exhibit these advantages, but they have defects which reduces the effectiveness. Such as super long after polymer pump, pipe and filter irreversible broken happens, therefore lost its useful properties. But the giant supramolecular won't happen. In spite of the supramolecular after pump will split smaller, this process is reversible. A single molecule chain at the end of the class nylon buckle unit can reconnect, when they met in the giant supramolecular produce effective recovery.
When added to the polymer concentration in the fuel is very low, giant supramolecular can not affect the other performance greatly change of the liquid fuel liquid. Such as additives, will not change the internal energy of the fuel, surface tension and density. In addition, the engine's power and efficiency of using fuel additive hasn't changed, at least at present, the diesel engine has been tested to prove it.
In collision occurs, the supramolecular suddenly perked up and curled to form compact conformation. When liquid suddenly stretched, polymer molecular chain unfolded against further stretch at the same time. Polymer stretching makes impact cases, droplet breakage, be suppressed, thus reduce the range of explosion at the same time reduce the turbulent flow in the piping.
Researchers Ming - Hsin "Jeremy Wei said:" the idea of a "giant supramolecular polymer from Yu Chaochang", "in the late 1970 s to the early 1980 s, the research of polymer scientists are keen to add long polymers into fuel to reduce the damage of the plane explosion". 1984 plane crash test completely examined this view, but the plane was swallowed by the fireball rapidly in the inspection, the negative news makes long polymer soon go unattended to.
In 2002, the JPL Virendra Sarohia Dr Control atomization experiments should be restored in case accident like September 11 attacks. He found Kornfield and persuaded him to design a new type of polymer to control the atomization of jet engines. 2006 Ameri David about giant supramolecular theory predicts that first breakthrough in the experiment, and then she graduate student David in the lab design, single molecule chain before it small enough to eliminate the problem, at the same time can in very low concentrations assembled together to form giant molecules. He believes the assembly has the advantages of long polymers, at the same time also has the condition through the pipeline and new performance of the filter.
Wei to join the team in 2007, he began to develop the theory of molecules. Was prepared with the ideal length of the polymer chain and make it ends with a strong enough "molecular buckles" is a challenge. In Robert Grubbs developed a catalyst for the help, Wei discovered the precise control of the molecular structure of the buckles and put it in the right location methods on the polymer chains.
The fusion of scientific research and engineering is the key to success. JPL chemical scientist Simon Jones help Wei developed using buckles and practical method for preparation of longer molecular chain end groups. Caltech student Boyu Li Wei help explore these new physics mechanism of the polymer under excited behavior. TARDEC scientist Joel Schmitigal implemented necessary test makes the polymer have been approved as a new type of fuel additive.
"If future want in thousands of gallons of jet fuel, diesel or gasoline this additive is added, we have to find a way to mass produce this kind of polymer", Wei said, "so my goal is to develop a continuous production of the polymer reactor, I plan to implement this goal within a year."
Kornfield said: "the most important thing is, we hope we can save lives, this new type of polymer minimize fuel casualties from the fire."
The study was published in Science.
