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eSwecha OS
Weave your own code
Introduction
e-Swecha (or Eswecha) is a free software project initiated by the Free Software Movement in India and is aimed at developing a free Operating System to, for and by the engineering students. The name is derived from "E(ngineering)- Swecha" [ Swecha is the Telugu word for 'freedom' ]
e-Swecha is a fruit of the tree of freedom sowed by the Free Software Movement.
Crucial inputs from a team of academicians, most of them teaching in various engineering colleges have been a major contribution to the project. Along with that, hundreds of free software communities and developers all around the world have helped in jumping over critical hurdles throughout the development of the project.
The GNU/Linux Operating system gives everyone the freedom to use, study, modify and distribute the software. This allowed the students to re-engineer the existing Operating System to the needs and requirements of the modern engineering student. By collaborating over the Internet and organizing themselves into different teams working on different modules, the Operating System was built with a tremendous show of team-work.
Eswecha is available in both live and installable CD. Beta version can be downloaded free from the Download link from the homepage of website: http://eswecha.swecha.org/?q=node/11
Technical Support is available through online chat and forum.
Eswecha launched
E-Swecha, the first Indian operating system created on free software platform was launched as beta version on Dec 23, 2008. It is being installed on 21,000 computers across Andhra Pradesh.
The operating system software, based on the Debian OS GNU/Linux, was created by the student community in engineering colleges in Hyderabad which is equipped with all the tools needed for engineering education. It is freely available to engineering students and others, in India or abroad.
(Richard Stallman)
He looks like a prophet, with his long grey hair and beard and intelligent eyes. In fact, in tech circles, Richard M Stallman is hailed as one. The `Father of Free Software’ is in Hyderabad to oversee the migration of thousands of computers
from proprietary to free software.
E-Swecha is based on the Debian OS which is a variant of GNU/Linux, the most popular open source OS. Unlike proprietary software like Microsoft Windows, open source software allows the original source code to be modified and distributed.
Thus the `free’ in free software
does not mean free of cost but free to be improved upon and redistributed. E-Swecha was developed by the student community in engineering colleges in Hyderabad. Apart from students, this collaborative effort involved academics and IT professionals and has been in development for a year. The OS has been developed to meet the syllabi needs of engineering students. It has all the tools that engineering students could possibly need on a single platform.
The Jawaharlal Nehru Technical University, Hyderabad which sets the engineering syllabus, has already taken the initiative to promote the usage of free software in colleges and has stood by its word by requesting for migration to e-Swecha OS. Some schools in Karnataka and West Bengal have also switched to FS
Stallman, in an interview acknowledged India’s efforts to switch to free software (FS). ``India is fairly high on FS though much remains to be done yet.’’ Kerala took the initiative by switching computers in its public schools to FS due to the efforts of the Free Software Foundation
of India, a sister organisation of the Free Software Foundation founded by Stallman.
Additional links:
1) e-Swecha free OS software website
http://eswecha.swecha.org/
2) Free OS for engineering students
http://infotech.indiatimes.com/News/Free_OS_for_engineering_students/articleshow/3877876.cms
3) Richard Stallman in Wikipedia
http://en.wikipedia.org/wiki/Richard_Stallman
4) Debian-The universal operating system
http://www.debian.org/
5) The GNU operating system
http://www.gnu.org/
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Inauguration ceremony for President Barack Obama on January 20, 2009
http://news.yahoo.com/s/ap/20090120/ap_on_go_pr_wh/inauguration_rdp
 |  Crowds of one million or more pack Washington D.C.'s National Mall for inauguration on January 20, 2009. |
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“Slumdog Millionaire” Wins Big At 66th Annual Golden Globes Awards
A.R. Rahman delivers his acceptance speech after receiving the Golden Globe award
http://www.masala.com/9757-all-we-can-say-for-rahman-is-jai-ho
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Reliance commissions world’s biggest refinery
http://www.indianexpress.com/news/reliance-commissions-worlds-biggest-refinery/402999/
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Scale of Gaza destruction emerges
http://news.bbc.co.uk/1/hi/world/middle_east/7836869.stm
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http://www.burjdubai.com/
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http://www.telegraphindia.com/1090112/jsp/opinion/story_10356034.jsp
SPENDING ISN’T ENOUGH
- The Centre’s package is insufficient to revive the economy
Commentator - S.L. Rao
In my last column, I wrote that the monetary, taxation and spending measures announced for reviving the economy were not adequate. To summarize, the government’s intention to spend is not enough. It must happen quickly and be spent efficiently. There must be a quick revamping so that efficient ministers and administrators are in charge of major expenditure programmes — like the National Highways Authorities of India, Rural Roads, National Rural Employment Guarantee scheme and Sarva Shiksha Abhiyan — to improve implementation. Lenders must resume lending. The government must institute a massive insurance programme to de-risk banks and lending institutions so that they resume lending with governmental guarantees against defaults. Housing, car and consumer-loan defaulters must be supported by the government through the lenders for a limited period until they revive. Excise duty reduction by 4 per cent could reduce some prices. But state governments must also sharply reduce registration costs for new properties for a limited period. India must enlarge its foreign exchange assets through borrowing maximum funds from multilateral institutions. The safety net for those laid off must be widened, with government guarantees of a portion of their last-drawn salaries, till they find other jobs. Blue-collar laid-off workers must be given special support.
The government has further cut the cash reserve ratio to improve liquidity, removed ceilings on external commercial borrowings, reduced interest rates, cut excise duties, will cut fuel prices further, and has added to the already massive expenditures proposed on infrastructure. All this is necessary, but how do you make people spend?
There is no change in administrative systems, procedures or people. There is no special scheme to reassure banks so that they resume lending. There is no action by state governments to reduce taxes or fees. We cannot expect any massive extra public expenditure in the near term for stimulating the economy. The government’s ambitious plans to spend massive amounts for infrastructure will remain bogged down in the procedural bottle-necks that have held up, for instance, the national roads programme under the United Progressive Alliance’s rule. Increasing public expenditure, through Keynesian means, does not have a chance of success because of the administrative morass that is development expenditure in India.
Removing limits on external borrowings is of theoretical value. For this to happen, there must be surplus funds overseas, foreign institutions confident enough to resume lending at all, interest costs must be lower than in India as they were early last year, and foreign lenders must have confidence in Indian companies to lend to them. That will depend on a global economic revival. The best guess seems to be that global revival is 18 months away. Hence, for India to benefit from external borrowing is to wait for 18 months.
Improved liquidity has not reached the banks and borrowers so far to any significant extent. It will remain scarce. One reason is the deficit in the balance of payments, which might increase as our major service exports get hit further. The Reserve Bank of India will have to continue selling dollars to prevent further erosion in the value of the rupee. Oil companies are still cash short. They will keep borrowing from banks on government bonds given in lieu of reimbursement of their below-cost sales of petroleum products. Others like the Food Corporation of India and fertilizer companies will also take away much of the extra liquidity.
Lower interest rates will benefit the bottom line of those who actually apply for and get loans. But banks are unlikely to increase lending when they are already refusing existing borrowers. Similarly, households in the income classes that use loans to buy houses and durable products, including cars, might well hold back from borrowing despite cheaper loans from banks, because of the general fear of a slowdown, possible loss of jobs and salary cuts, and the desire to have as much saved up funds as possible. Much new borrowing and spending activity will not take place merely because interest rates are lower.
What we have to avoid is defaults on old housing and consumer loans. These will crash the market far more than we have experienced so far. Manufacturers and housing providers will then find it even more difficult to raise money. Banks will lose confidence and further avoid lending to companies and households. A safety net for banks whose customers are losing jobs or defaulting because of the economic situation is an urgent necessity. Export units in goods and services will also need support, so that they can continue employment till export and domestic demand improve. Government guarantees for loans against their assets might be an answer that banks might accept.
The Administrative Reforms Commission must quickly cut through the procedural quicksand that our bureaucracy has created at the Centre and states and that has slowed down public investment as well as investment in public private partnerships. The government must ask the Supreme Court to immediately speed up environmental approvals now held up in the Supreme Court committees, so that large projects can get going.
Inefficient states like Karnataka or Maharashtra have allowed complex procedures, lack of accountability, interfering political families and poor planning to hold up project concepts and implementation. They must be told that they will lose Central funding altogether for these projects if they do not get moving immediately. The Centre should give them help in this speeding up.
We are still hankering for the volatile foreign institutional funds to come into our stock markets and take advantage of the exemption given them from short-term capital gains tax. Instead, this is a good time to gradually put an end to this special treatment for volatile funds that collapsed our stock markets and the rupee’s exchange value.
For the future, we must turn our backs on the old days of soft regulation following the Americans, respecting their high sophistication in financial regulation. The American system failed and we must make sure that ours does not. Regulators must play a much larger role in regulating financial products and practices than they have done. They should stop rating agencies being paid by clients. Instead, the regulator must pay for the ratings and raise fees from individual ratees. Quality standards must be laid down, monitored and enforced for rating agencies, who must be barred from earning anything else from clients rated by them. The regulator must review the quality and reliability of the ratings given by each agency.
We must close the door to easy entry by overseas banks and financial institutions. New financial products must be evaluated first by the regulator before a bank or other body is allowed to market them in India. Regulators must look for and eliminate off-balance-sheet items. In the financial world, securitization, credit default swaps, and such other practices must be subject to full disclosure of the components and their standing. Corporate books will close in March. Companies that borrowed overseas will show large hits because of the rupee decline. The Securities and Exchange Board of India must consider if it should get the Institute of Chartered Accountants to grant a one-time waiver for six months from marking all such liabilities to market. Of course, this is a fudge and should not be repeated. But it will avoid a flood of bad corporate results from further devastating the market.
The present package is insufficient to revive the economy. It ignores the hidden factors of confidence and expectations that need to be revived. We must urgently improve the ability of the administration to clear projects and allow them to be executed without hindrance.
The author is former director-general, National Council for Applied Economic Research
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http://news.yahoo.com/s/ap/20090124/ap_on_go_pr_wh/obama_economy
By PHILIP ELLIOTT, Associated Press Writer Philip Elliott, Associated Press Writer – 24 January, 2009
WASHINGTON – President Barack Obama took to the airwaves Saturday to promote his economic aid plan in what's-it-mean-to-me terms: thousands of better schools, lower electricity bills, health coverage for millions who lose insurance.
It was the latest appeal from the new president for a massive spending bill designed to inject almost $1 trillion into the economy and fulfill campaign pledges. As lawmakers consider an $825 billion plan and Obama woos them, he used his first radio and Internet address from the White House to update the public about his goals.
"Our economy could fall $1 trillion short of its full capacity, which translates into more than $12,000 in lost income for a family of four. And we could lose a generation of potential, as more young Americans are forced to forgo college dreams or the chance to train for the jobs of the future," Obama said in a five-minute address.
"In short, if we do not act boldly and swiftly, a bad situation could become dramatically worse."
Along with the speech, Obama's economic team released a report designed to outline tangible benefits of the plan and shore up support. Aides said they wanted people to understand exactly what they could expect if Congress supported the proposed legislation.
The United States lost 2.6 million jobs last year, the most in any single year since World War II. Manufacturing is at a 28-year low and even Obama's economists say unemployment could top 10 percent before the recession ends. One in 10 homeowners is at risk of foreclosure and the dollar continues its slide in value.
That harsh reality has dominated Obama's first days in office. He scheduled a meeting late Saturday morning with his economic team.
A day earlier, he invited Democratic and Republican leaders to the White House to hear their ideas on the economy. At that visit, he did not share the details he released Saturday.
Many of the goals in the speech and report were familiar from Obama's two-year campaign, such as shifting to electronic medical records and investing in preventive health care. Other parts added specifics.
Obama's recovery package aims to:
_double within three years the amount of energy that could be produced from renewable resources. That is an ambitious goal, given the 30 years it took to reach current levels. Advisers say that could power 6 million households.
_upgrade 10,000 schools and improve learning for about 5 million students.
_save $2 billion a year by making federal buildings energy efficient.
_triple the number of undergraduate and graduate fellowships in science.
_tighten security at 90 major ports.
The plan would spend at least 75 percent of the total cost — or more than $600 billion — within the first 18 months, either through bricks-and-shovels projects favored by Democrats or tax cuts that Republicans have pushed.
There is heavy emphasis on public works projects, which have lagged as state budgets contracted. Governors have lobbied Obama to help them patch holes in their budgets, drained by sinking tax revenues and increased need for public assistance such as Medicaid and children's health insurance. Obama's plan would increase the federal portion of those programs so no state would have to cut any of the 20 million children whose eligibility is now at risk.
Obama's plan would also provide health care coverage for 8.5 million people who lose their insurance when they either lose or shift jobs.
"It's a plan that will save or create 3 to 4 million jobs over the next few years" and recognizes "there are millions of Americans trying to find work even as, all around the country, there's so much work to be done," he said.
But he cautioned again against expecting instant results: "No one policy or program will solve the challenges we face right now, nor will this crisis recede in a short period of time."
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On the Net:
Obama video: http://www.whitehouse.gov.
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http://www.sciencedaily.com/releases/2009/01/090106145008.htm
ScienceDaily (Jan. 7, 2009) — A team of University of Toronto physicists have demonstrated a new technique to squeeze light to the fundamental quantum limit, a finding that has potential applications for high-precision measurement, next-generation atomic clocks, novel quantum computing and our most fundamental understanding of the universe.
 A progression of squeezed triphoton states spiraling outwards. The quantum uncertainty in the triphotons can be represented as a blob on a sphere that becomes progressively "squeezed". (Credit: Victoria Feistner) |
Krister Shalm, Rob Adamson and Aephraim Steinberg of U of T´s Department of Physics and Centre for Quantum Information and Quantum Control, publish their findings in the January 1 issue of the international journal Nature.
"Precise measurement lies at the heart of all experimental science: the more accurately we can measure something the more information we can obtain. In the quantum world, where things get ever-smaller, accuracy of measurement becomes more and more elusive," explains PhD graduate student Krister Shalm.
Light is one of the most precise measuring tools in physics and has been used to probe fundamental questions in science ranging from special relativity to questions concerning quantum gravity. But light has its limits in the world of modern quantum technology.
The smallest particle of light is a photon and it is so small that an ordinary light bulb emits billions of photons in a trillionth of a second.. "Despite the unimaginably effervescent nature of these tiny particles, modern quantum technologies rely on single photons to store and manipulate information. But uncertainty, also known as quantum noise, gets in the way of the information," explains Professor Aephraim Steinberg.
Squeezing is a way to increase certainty in one quantity such as position or speed but it does so at a cost. "If you squeeze the certainty of one property that is of particular interest, the uncertainty of another complementary property inevitably grows," he says.
In the U of T experiment, the physicists combined three separate photons of light together inside an optical fibre, to create a triphoton. "A strange feature of quantum physics is that when several identical photons are combined, as they are in optical fibres such as those used to carry the internet to our homes, they undergo an "identity crisis" and one can no longer tell what an individual photon is doing," Steinberg says. The authors then squeezed the triphotonic state to glean the quantum information that was encoded in the triphoton´s polarization. (Polarization is a property of light which is at the basis of 3D movies, glare-reducing sunglasses, and a coming wave of advanced technologies such as quantum cryptography.)
In all previous work, it was assumed that one could squeeze indefinitely, simply tolerating the growth of uncertainty in the uninteresting direction. "But the world of polarization, like the Earth, is not flat," says Steinberg.
"A state of polarization can be thought of as a small continent floating on a sphere. When we squeezed our triphoton continent, at first all proceeded as in earlier experiments. But when we squeezed sufficiently hard, the continent lengthened so much that it began to "wrap around" the surface of the sphere," he says.
"To take the metaphor further, all previous experiments were confined to such small areas that the sphere, like your home town, looked as though it was flat. This work needed to map the triphoton on a globe, which we represented on a sphere providing an intuitive and easily applicable visualization. In so doing, we showed for the first time that the spherical nature of polarization creates qualitatively different states and places a limit on how much squeezing is possible," says Steinberg.
"Creating this special combined state allows the limits to squeezing to be properly studied," says Rob Adamson. "For the first time, we have demonstrated a technique for generating any desired triphoton state and shown that the spherical nature of polarization states of light has unavoidable consequences. Simply put: to properly visualize quantum states of light, one should draw them on a sphere."
Adapted from materials provided by University of Toronto.
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http://www.newscientist.com/article/dn16374-repulsive-quantum-effect-finally-measured.html
A quantum effect that causes objects to repel one another - first predicted almost 50 years ago - has at last been seen in the lab.
 Artist's rendition of how a repulsive quantum force between nanoscale objects can allow an object to become "bouyant" on a liquid less dense than itself (Image: Jay Penni/Federico Capasso) |
According to Harvard physicist Federico Capasso, a member of the group who measured the effect, it could be used to lubricate future nanomachines.
The team detected the weak repulsive force when they brought together a thin sheet of silica and a small gold-plated bead, about half the diameter of a human hair.
The force is an example of the Casimir effect, generated by all-pervasive quantum fluctuations.
Strange attraction
The simplest way to imagine the Casimir force in action is to place two parallel metal plates in a vacuum. Thanks to the odd quantum phenomenon, these become attracted to one another.
It happens because even a vacuum is actually fizzing with a quantum field of particles, constantly popping in and out of existence. They can even fleetingly interact with and push on the plates.
However, the small space between the two plates restricts the kind of particles that can appear, so the pressure from behind the plates overwhelms that from between them. The result is an attractive force that gums up nanoscale machines. (To learn more about the Casimir force see Under pressure from quantum foam.)
Capasso says that the Casimir force needn't be an enemy. "Micromechanics at some point will have to contend with these forces - or make use of them."
Reverse buoyancy
In 1961, Russian theorists calculated that in certain circumstances, the Casimir effect could cause objects to repel one another - a scenario Capasso's team have finally created experimentally. The team achieved this by adding a fluid, bromobenzene, to the setup.
The Casimir attraction between the liquid and the silica plate is stronger than that between the gold bead and the silica, so the fluid forces its way around the bead, pushing it away from the plate.
The effect is akin to the buoyancy we experience in the macro world - where objects less dense than water are held up by the liquid around them. But in this case the bromobenzene is less dense than the solid bead. "You could call it quantum buoyancy," Capasso told New Scientist.
The force he measured was feeble - amounting to just a few tens of piconewtons - but that is still enough to buoy up nanoscale objects.
Quantum bearings
"The next experiment we want to do is use a TV camera to track the motion of one of these spheres, then we should be able to see easily whether you have levitation."
Harnessing the repulsive Casimir force could provide a kind of lubrication to solve the problem of nanomachines becoming gummed up by the better-known attractive version, says Capasso.
In theory you could instead use a liquid denser than the components to buoy them up, but that wouldn't be practical. "These gizmos are usually made of metal, so you would have to use mercury," he explains.
Quantum buoyancy bearings could be used to build delicate sensors, such as a floating "nanocompass" to detect small-scale magnetic fields.
Journal reference: Nature (DOI: 10.1038/nature07610)
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By Tim De Chant | Published: January 15, 2009 - 01:00PM CT
For centuries, humans have dreamed of fading into the background. Hunters have long wished to vanish into their surroundings, and these days, awkward moments at parties can evoke similar desires. But the ability to truly disappear is still only found in tales spun by writers and filmmakers, as cloaking has remained the stuff of fantasy and science fiction. Thanks to some pioneering researchers, however, cloaking has moved one step closer to reality.
Six scientists have built a sophisticated metamaterial that literally bends electromagnetic waves, according to a new paper published Thursday in the journal Science. Ruopeng Liu and Chunlin Li, researchers in David R. Smith’s lab at Duke University, along with three other colleagues, assembled more than 10,000 specially designed pieces to form a mat 20 inches long and four inches wide. When finished, the yellow pad sucked microwaves in and spit them out—with a curve.
To test their new invention, researchers first beamed microwaves at a flat, mirrored surface. The waves behaved as they should, bouncing off at a predictable angle. Next they shot it at a bump in a mirrored surface. The microwaves bounced and scattered, carefully obeying the laws of physics. Then the scientists laid their yellow mat over the bump. And the wave ignored the bump—or so it seemed. After reflecting off the curved surface, the radiation veered downward and continued along a flat surface-trajectory. The mat had cloaked the bump.
The results of the new study. Microwaves bounce off a flat surface in (A) while they both bounce and scatter off the curved surface in (B). With the new cloaking material, various frequencies of microwaves curve after they leave the curved surface (C through F), making it appear to sensors as though the surface were flat. Image courtesy AAAS/Science
Aside from starring in the Harry Potter series and countless Star Trek incarnations, cloaking has been a very serious and very active research area in the past few years. In May 2006, two scientists proposed active cloaking devices based on superlenses, but their contribution at the time was only theoretical. The reality of superlenses hasn't been as promising, but in October of that same year, Smith and his colleagues presented a cloaking breakthrough—the ability to cloak an object from a specific microwave frequency. More papers followed, and the science progressed rapidly. But then last December, a new theoretical study published gave researchers a harsh reality check—cloaking at multiple frequencies may very well be impossible, the authors said. As the number of cloaked frequencies increases, the efficacy of the device or material decreases. It’s a classic tradeoff, they implied, and one not likely to be overcome.
Liu and Li’s new research, though, seems to poke a giant hole in that last paper. Their new metamaterial masks not one tiny slice of the microwave spectrum, but a relatively large swath of it, from 13 to 16 gigahertz. Liu and Li built off the results of Smith’s 2006 paper to create the new cloak, but this time used more powerful algorithm to help them fabricate the metamaterial. The formula dictated where each of the over 10,000 pieces in the structure should be placed to achieve the desired effect.
"The difference between the original device and the latest model is like night and day," Smith said in a press release. While the earlier, more limited device took Smith and his team four months to build, the new, more capable cloak was ready in only nine days.
Smith compares the mat’s cloaking effect to a mirage. "You see what looks like water hovering over the road, but it is in reality a reflection from the sky," he said. "The mirage you see is cloaking the road below."
While you won’t be able to don a fancy blanket and duck out of work early any time soon, the new metamaterial proves that one surface can cloak many frequencies. Three gigahertz is certainly a far cry from the 350,000 GHz that make up the visible spectrum, but at least it’s a step in the right direction.
Science, 2008. DOI: 10.1126/science.1166949
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http://www.space-travel.com/reports/Researchers_Cooking_Up_New_Gelled_Rocket_Fuels_999.html
by Emil Venere
for Purdue News
West Lafayette IN (SPX) Jan 22, 2009
Engineers and food scientists are teaming up to develop a new type of gelled fuel the consistency of orange marmalade designed to improve the safety, performance and range of rockets for space and military applications.
"This is a very multidisciplinary project," said Stephen Heister, the Purdue University professor of aeronautics and astronautics who is leading one of two teams on the project, which is funded by the U.S. Army Research Office.
Timothee Pourpoint, a research assistant professor of aeronautics and astronautics, is in charge of designing and operating a new Purdue lab to test gelled rocket fuels that have the consistency of orange marmalade. The fuels are designed to improve the safety, performance and range of rockets for space and military applications, and the research will involve a team of engineers and food scientists. Standing in the new lab are, from left, Tim Phillips and Mark James, both graduate students in aeronautics and astronautics, Pourpoint and Travis Kubal, a graduate student in mechanical engineering. (Purdue News Service photo/Andrew Hancock)
Gels are inherently safer than liquids because they don't leak, and they also would allow the military to better control rockets than is possible with solid fuels now used. Motors running on gelled fuels could be throttled up and down and controlled more precisely than conventional rockets that use solid propellants, Heister said.
"You can turn the engine on and off, you can coast, go fast or slow," he said. "You have much greater control, which means more range for missiles. The gelled propellants also tend to have a little more energy than the solid propellants."
Gelled fuels also could be used in thrusters to position satellites and on NASA space missions.
The team includes researchers from mechanical engineering, aeronautics and astronautics, food science, and agricultural and biological engineering at Purdue, as well as researchers from Iowa State University and University of Massachusetts.
Paul Sojka, a professor of mechanical engineering and an associate director of the project, is building an experiment to take high-speed videos of the gelatinous fuel's behavior. Jets of the gel form during the fuel-injection process.
"These jets are wiggling, there are pulsations, and those pulsations, we believe, lead to the formation of specific spray patterns and droplet formation," Sojka said. "The fluid mechanics of gels are quite challenging. The viscous properties of the gel change depending on how fast it's flowing, which is not true of common liquids such as water or gasoline."
The project will tap the expertise of food scientists and food engineers, who are accustomed to working with gels, said Carlos Corvalan, an associate professor of food science.
"Gels are more complex than ordinary solids and fluids," Corvalan said. "Fluids are characterized by viscosity, and solids are characterized by elasticity. Because gels share properties of both solids and fluids, they possess viscoelastic properties, or a combination of both."
Food science and agricultural engineering researchers will study these viscoelastic properties and create simulations describing how the gels behave.
The five-year, $6.4 million "spray and combustion of gelled hypergolic propellants" project is a U.S. Army Multidisciplinary University Research Initiative, or MURI. Another team is led by Pennsylvania State University.
Future rockets could require that gelled propellants be sprayed by fuel injectors into a motor's combustion chamber at rates of thousands of pounds per second. Using the gelled propellants, however, will require a thorough knowledge of how the fuel breaks into droplets as it is being sprayed into the chamber.
The fuels are hypergolic, meaning they require no ignition source but ignite spontaneously when mixed with an oxidizer. The fuel and oxidizer tanks each feed into a separate fuel injector. As the streams of fuel and oxidizer mix, they form droplets that ignite.
"There is an unsteadiness of these two jets, and these fluctuations can have all sorts of ramifications in terms of engine performance," said Sojka, who specializes in research to learn what happens between the fuel and oxidizer streams as they form elliptical sheets, spaghetti-like strands and droplets.
The high-speed movies are recorded at about 10,000 frames per second, or roughly 300 times faster than the typical video signal.
The collision of fuel and oxidizer jets causes "impact waves."
"We are trying to understand the source of those waves and be able to control or capitalize on the unsteadiness to make smooth combustion," Heister said.
Purdue faculty members and graduate students are conducting experiments at the university's Maurice J. Zucrow Laboratories, in the Department of Food Science and in the School of Agricultural and Biological Engineering aimed at developing a comprehensive spray model that describes the precise behavior of propellant droplets in a rocket motor.
One aim is to be able to consistently create the relatively small, uniform droplets that would be needed for rocket propulsion. Food scientists are familiar with processes used to create droplets in foods.
"The texture of those foods is closely associated with the average size and range of sizes of droplets," said Osvaldo Campanella, a professor of agricultural and biological engineering. "In a combustion chamber you also want to control droplet size, but for a different reason - to precisely control combustion. You want uniform combustion, and for that you need controlled drop size."
Corvalan will lead work to develop simulations that determine the viscoelastic behavior of the gels and droplets.
Researchers will first work with water-based gels that simulate fuels and will eventually conduct experiments using actual propellants.
"It's kind of like orange marmalade without the rind," Heister said. "We are going to make this gel and push it through holes and study how it flows and how big the drops are. Eventually we'll study the real gelled fuels, which can be quite hazardous and reactive, so we will use them in small quantities and under tightly controlled conditions."
The viscoelastic properties of the gels will not only be experimentally measured, but molecular models representing the gels also will be developed as part of research in Purdue's Department of Chemistry. The models will enable researchers to predict the behavior of gels and optimize their formulations.
Information from experiments and modeling will be used to design systems that have improved combustion.
Timothee Pourpoint, a research assistant professor of aeronautics and astronautics, is in charge of setting up and maintaining a propulsion lab to test the fuels at Zucrow. Because the fuels being tested are toxic, the lab will be equipped with a specialized ventilation system. Pourpoint conducted extensive research on hypergolic fuels for his doctoral thesis at Purdue.
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