3-D printed engines could support human missions to deep space.
3-D printed complex subscale injector A 3-D printed rocket part blazes to life during a hot-fire test designed to explore how well large rocket engine components withstand temperatures up to 6,000 degrees Fahrenheit and extreme pressures, typical of the environments experienced by rocket engines. NASA/MSFC/NASA/David Olive
In NASA's latest exploration of combining 3-D printing and space travel, the agency ran tests on the largest ever 3-D printed rocket engine component at the Marshall Space Flight Center.
Researchers at Chalmers University of Technology have developed a unique integrated motor drive and battery charger for electric vehicles. Compared to today's electric vehicle chargers, they have managed to shorten the charging time from eight to two hours, and to reduce the cost by around $2,000.
Saeid Haghbin, doctor of electric power engineering, undertook his doctoral studies in order to develop the optimal electric vehicle charger. The result is a novel high-power integrated motor drive and battery charger for vehicle applications, where a new power transfer method has been introduced involving what is known as a rotating transformer.
Model of the integrated motor drive and battery charger. The image shows a plug-in hybrid electric vehicle, which also has a fuel tank and a combustion engine, but the technology system works equally well with a purely electric vehicle. (Credit: Image courtesy of Chalmers University of Technology)
"The ideal scenario would be to have a charger powerful enough to charge a car in five to ten minutes, but this would cost over $100,000, which is more expensive than the car itself," says Saeid Haghbin. "The question we posed was: how can we reduce the size, weight and price of the on-board charger."
Since the electric motor and the inverter are not used during battery charging, the researchers looked into the possibility of using them in the charger circuit and building some kind of integrated motor and battery charger. In other words, would it be possible to use the motor and inverter in the charger circuit to increase the charging power at a lower cost?
"Instead of having a separate isolated battery charger, we introduced a new concept for the power transfer, the rotating transformer, which was developed to transfer electric power while rotating," says Saeid Haghbin. "The battery is charged through the transformer and a split-phase electric motor that was especially designed for this purpose."
The Chalmers integrated charger is, from a university perspective, still on laboratory level. To achieve a more optimal system, further investigations and experimentation are necessary. However, the product has resulted in both a Swedish and an international patent. Chalmers is trying to find a potential industrial user, and Volvo AB is working on the concept for further enhancement to be used in its system.
"Electric cars have been discussed as a possible solution to reduce carbon emissions for a long time, but scientists debate whether this mode of transportation is the future or not," says Saeid Haghbin. "If we manage to solve the main problems with the battery and the battery chargers, I think the electric vehicles will succeed. And in general, I think electric transportation will become more common in the future, for example trains, trams and plug-in hybrids."
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The Online Electric Vehicle (OLEV), developed by the Korea Advanced Institute of Science and Technology (KAIST), is an electric vehicle that can be charged while stationary or driving, thus removing the need to stop at a charging station. Likewise, an OLEV tram does not require pantographs to feed power from electric wires strung above the tram route.
Following the development and operation of commercialized OLEV trams (at an amusement park in Seoul) and shuttle buses (at KAIST campus), respectively, the City of Gumi in South Korea, beginning on August 6th, is providing its citizens with OLEV public transportation services.
Two OLEV buses will run an inner city route between Gumi Train Station and In-dong district, for a total of 24 km roundtrip. The bus will receive 20 kHz and 100 kW (136 horsepower) electricity at an 85% maximum power transmission efficiency rate while maintaining a 17cm air gap between the underbody of the vehicle and the road surface.
The Online Electric Vehicle (OLEV), developed by the Korea Advanced Institute of Science and Technology (KAIST), is an electric vehicle that can be charged while stationary or driving, thus removing the need to stop at a charging station. (Credit: Image courtesy of ResearchSEA)
OLEV is a groundbreaking technology that accelerates the development of purely electric vehicles as a viable option for future transportation systems, be they personal vehicles or public transit. This is accomplished by solving technological issues that limit the commercialization of electric vehicles such as price, weight, volume, driving distance, and lack of charging infrastructure.
OLEV receives power wirelessly through the application of the "Shaped Magnetic Field in Resonance (SMFIR)" technology. SMFIR is a new technology introduced by KAIST that enables electric vehicles to transfer electricity wirelessly from the road surface while moving. Power comes from the electrical cables buried under the surface of the road, creating magnetic fields. There is a receiving device installed on the underbody of the OLEV that converts these fields into electricity. The length of power strips installed under the road is generally 5%-15% of the entire road, requiring only a few sections of the road to be rebuilt with the embedded cables.
OLEV has a small battery (one-third of the size of the battery equipped with a regular electric car). The vehicle complies with the international electromagnetic fields (EMF) standards of 62.5 mG, within the margin of safety level necessary for human health. The road has a smart function as well, to distinguish OLEV buses from regular cars -- the segment technology is employed to control the power supply by switching on the power strip when OLEV buses pass along, but switching it off for other vehicles, thereby preventing EMF exposure and standby power consumption. As of today, the SMFIR technology supplies 60 kHz and 180 kW of power remotely to transport vehicles at a stable, constant rate.
Dong-Ho Cho, a professor of the electrical engineering and the director of the Center for Wireless Power Transfer Technology Business Development at KAIST, said: "It's quite remarkable that we succeeded with the OLEV project so that buses are offering public transportation services to passengers. This is certainly a turning point for OLEV to become more commercialized and widely accepted for mass transportation in our daily living."
After the successful operation of the two OLEV buses by the end of this year, Gumi City plans to provide ten more such buses by 2015.
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Aug. 29, 2013 — Looking for a parking space for hours at a busy shopping mall or being stuck on roads jammed with cars releasing large amounts of carbon dioxide are all-too-familiar scenes for city dwellers.
A group of researchers at the Korea Advanced Institute of Science and Technology (KAIST) recently developed a possible solution to such problems: a foldable, compact electric vehicle that can be utilized either as a personal car or part of the public transit system to connect major transportation routes within a city.
In-Soo Suh, Associate Professor of the Graduate School for Green Transportation at KAIST and his research team introduced a prototype micro electric car called "Armadillo-T," whose design is based on a native animal of South America, the armadillo, a placental mammal with a leathery armor shell.
Armadillo-T is a small and light pure-electric car that can fold in half for convenient parking. (Credit: Image courtesy of KAIST)
The research team imitated the animal's distinctive protection characteristic of rolling up into a ball when facing with threat from predators. Just as armadillos hide themselves inside the shell, Armadillo-T tucks its rear body away, shrinking its original size of 2.8 meters (110 inches) down to almost half, 1.65 meters (65 inches), when folding.
The Armadillo-T Prototype folds itself nearly in half with the touch of a smartphone button.
Armadillo-T is a four-wheel-drive, all-electric car with two seats and four in-wheel motors. Since the motors are installed inside the wheels, and the 13.6 kWh capacity of lithium-ion battery pack is housed on the front side, the battery and motors do not have to change their positions when the car folds. This not only optimizes the energy efficiency but also provides stability and ample room to drivers and passengers.
Once folded, the small and light (weighs 450 kg) electric vehicle takes up only one-third of a 5-meter parking space, the standard parking size in Korea, allowing three of its kind to be parked. With a smartphone-interfaced remote control on the wheels, the vehicle can turn 360 degrees, enhancing drivers' convenience to park the car, even in an odd space in a parking lot, the corner of a building, for example.
Professor In-Soo Suh said, "I expect that people living in cities will eventually shift their preferences from bulky, petro-engine cars to smaller and lighter electric cars. Armadillo-T can be one of the alternatives city drivers can opt for. Particularly, this car is ideal for urban travels, including car-sharing and transit transfer, to offer major transportation links in a city. In addition to the urban application, local near-distance travels such as tourist zones or large buildings can be another example of application."
The concept car has loads of smart features on board, too: the cameras installed inside the car eliminate the need for side mirrors and increase the driver's ability to see the car's right and left side, thereby reducing blind spots. With a smartphone, the driver can control Armadillo-T and enable remote folding control. The car has a maximum speed of 60 km/h, and with a ten-minute fast charge, it can run up to 100 km.
Professor Suh explained that the concept of Armadillo-T was originally initiated in 2011 as he focused his research interest on the sub-A segment of personal mobility vehicles (PMVs), which are smaller and lighter than the current compact cars, as a new personalized transport mode.
"In coming years, we will see more mega-size cities established and face more serious environmental problems. Throughout the world, the aging population is rapidly growing as well. To cope with climate, energy, and limited petroleum resources, we really need to think outside the box, once again, to find more convenient and eco-friendly transportation, just as the Ford Model T did in the early 1920s. A further level of R&D, technical standards, and regulatory reviews are required to have these types of micro vehicles or PMVs on the market through test-bed evaluations, but we believe that Armadillo-T is an icon toward the future transport system with technology innovation."
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Aug. 23, 2013 — It is well known to scientists that the three common phases of water -- ice, liquid and vapor -- can exist stably together only at a particular temperature and pressure, called the triple point.
Also well known is that the solid form of many materials can have numerous phases, but it is difficult to pinpoint the temperature and pressure for the points at which three solid phases can coexist stably.
The lines of data points are where two of the three solid-state phases of vanadium dioxide
can exist stably together, and the point where the three lines meet -- the triple point --
is where all three phases can exist together. (Credit: David Cobden/University of Washington)
Scientists now have made the first-ever accurate determination of a solid-state triple point in a substance called vanadium dioxide, which is known for switching rapidly -- in as little as one 10-trillionth of a second -- from an electrical insulator to a conductor, and thus could be useful in various technologies.
"These solid-state triple points are fiendishly difficult to study, essentially because the different shapes of the solid phases makes it hard for them to match up happily at their interfaces," said David Cobden, a University of Washington physics professor.
"There are, in theory, many triple points hidden inside a solid, but they are very rarely probed."
Cobden is the lead author of a paper describing the work, published Aug. 22 in Nature.
In 1959, researchers at Bell Laboratories discovered vanadium dioxide's ability to rearrange electrons and shift from an insulator to a conductor, called a metal-insulator transition. Twenty years later it was discovered that there are two slightly different insulating phases.
The new research shows that those two insulating phases and the conducting phase in solid vanadium dioxide can coexist stably at 65 degrees Celsius, give or take a tenth of a degree (65 degrees C is equal to 149 degrees Fahrenheit).
To find that triple point, Cobden's team stretched vanadium dioxide nanowires under a microscope. The team had to build an apparatus to stretch the tiny wires without breaking them, and it was the stretching that allowed the observation of the triple point, Cobden said.
It turned out that when the material manifested its triple point, no force was being applied -- the wires were not being stretched or compressed.
The researchers originally set out simply to learn more about the phase transition and only gradually realized that the triple point was key to it, Cobden said. That process took several years, and then it took a couple more to design an experiment to pin down the triple point.
"No previous experiment was able to investigate the properties around the triple point," he said.
He regards the work as "just a step, but a significant step" in understanding the metal-insulator transition in vanadium dioxide. That could lead to development of new types of electrical and optical switches, Cobden said, and similar experiments could lead to breakthroughs with other materials.
"If you don't know the triple point, you don't know the basic facts about this phase transition," he said. "You will never be able to make use of the transition unless you understand it better."
Aug. 22, 2013 — One of the most promising types of solar cells has a few drawbacks. A scientist at Michigan Technological University may have overcome one of them.
Dye-sensitized solar cells are thin, flexible, easy to make and very good at turning sunshine into electricity. However, a key ingredient is one of the most expensive metals on the planet: platinum. While only small amounts are needed, at $1,500 an ounce, the cost of the silvery metal is still significant.
A field emission scanning electron microscopy (FESEM) image
of 3D honeycomb-structured graphene. The novel material can
replace platinum in dye-sensitized solar cells with virtually
no loss of generating capacity. (Credit: Hui Wang)
Yun Hang Hu, the Charles and Caroll McArthur Professor of Materials Science and Engineering, has developed a new, inexpensive material that could replace the platinum in solar cells without degrading their efficiency: 3D graphene.
Regular graphene is a famously two-dimensional form of carbon just a molecule or so thick. Hu and his team invented a novel approach to synthesize a unique 3D version with a honeycomb-like structure. To do so, they combined lithium oxide with carbon monoxide in a chemical reaction that forms lithium carbonate (Li2CO3) and the honeycomb graphene. The Li2CO3 helps shape the graphene sheets and isolates them from each other, preventing the formation of garden-variety graphite. Furthermore, the Li2CO3 particles can be easily removed from 3D honeycomb-structured graphene by an acid.
The researchers determined that the 3D honeycomb graphene had excellent conductivity and high catalytic activity, raising the possibility that it could be used for energy storage and conversion. So they replaced the platinum counter electrode in a dye-sensitized solar cell with one made of the 3D honeycomb graphene. Then they put the solar cell in the sunshine and measured its output.
The cell with the 3D graphene counter electrode converted 7.8 percent of the sun's energy into electricity, nearly as much as the conventional solar cell using costly platinum (8 percent).
Synthesizing the 3D honeycomb graphene is neither expensive nor difficult, said Hu, and making it into a counter electrode posed no special challenges.
The research has been funded by the American Chemical Society Petroleum Research Fund (PRF-51799-ND10) and the National Science Foundation (NSF-CBET-0931587).
Jet Pumps are mounted above ground and lift the water out of the ground through a suction pipe. Jets are popular in areas with high water tables and warmer climates.
There are two categories of jet pumps and pump selection varies depending on water level.
Shallow well installations go down to a water depth of about 25 feet (7.62 m).
Deep wells are down 150 feet (45.72 m) to water, where surface pumps are involved.
The jet pump is a centrifugal pump with one or more impeller and diffuser with the addition of a jet ejector.
A JET EJECTOR consists of a matched nozzle and venturi.
The nozzle receives water at high pressure. As the water passes through the jet, water speed (velocity) is greatly increased, but the pressure drops. This action is the same as the squirting action you get with a garden hose as when you start to close the nozzle.
The greatly increased water speed plus the low pressure around the nozzle tip, is what causes suction to develop around the jet nozzle. Water around a jet nozzle is drawn into the water stream and carried along with it.
For a jet nozzle to be effective it must be combined with a venturi. The venturi changes the high-speed jet stream back to a high-pressure for delivery to the centrifugal pump. The jet and venturi are simple in appearance but they have to be well engineered and carefully matched to be efficient for various pumping conditions. The jet nozzle and venturi are also known as ejectors/ejector kits.
On a shallow-well jet pump the ejector kit (jet nozzle and venturi) is located in the pump housing in front of the impeller. A portion of the suction water is recirculated through the ejector with the rest going to the pressure tank. With the ejector located on the suction side of the pump, the suction is increased considerably.
This enables a centrifugal pump to increase its effective suction lift from about 20 feet to as much as 28 feet.
But, the amount of water delivered to the storage tank becomes less as the distance from the pump to the water increases… more water has to be recirculated to operate the ejector.
The difference between a deep-well jet pump and a shallow-well jet pump is the location of the ejector.
The deep-well ejector is located in the well below the water level. The deep-well ejector works in the same way as the shallow-well ejector. Water is supplied to it under pressure from the pump. The ejector then returns the water plus an additional supply from the well, to a level where the centrifugal pump can lift it the rest of the way by suction.
A convertible jet pump allows for shallow well operation with the ejector mounted on the end of the pump body. This type of pump can be converted to a deep-well jet pump by installing the ejector below the water level.
This is of particular value when you have a water level that is gradually lowering. This will probably require a change of venturi to work efficiently. Because jet pumps are centrifugal pumps, the air handling characteristics are such that the pump should be started with the pump and piping connections to the water supply completely filled with water.
With a shallow-well jet pump, the ejector is mounted close to the pump impeller. With a deep well jet pump, the ejector is usually mounted just above the water level in the well, or else submerged below water level.
Centrifugal pumps, both the shallow-well and deep well types have little or no ability to pump air. When starting, the pump and suction line needs to have all of the air removed. An air leak in the suction line will cause the pump to quit pumping … or sometimes referred to as “losing its prime”.
How a jet provides pumping action?
Water is supplied to the Jet ejector under pressure. Water surrounding the jet stream is lifted and carried up the pipe as a result of the jet action.
When a jet is used with a centrifugal pump a portion of the water delivered by the pump is returned to the jet ejector to operate it. The jet lifts water from the well to a level where the centrifugal pump can finish lifting It by suction.
Earth is the water planet. What if you could take all of the water on Earth and form it into a sphere? How big would it be?
We think of Earth as the water planet. But what if you could take all of the water on Earth and form it into a sphere, or bubble? How big would the bubble be? The U.S. Geological Survey (USGS) has the answer. All the water on Earth would fit into a sphere 860 miles (1,385 km) wide. That’s a lot smaller than Earth itself, as the drawing below shows.
All the water on Earth would fit into a sphere 860 miles (1,385 km) wide. Image via Jack Cook/WHOI/USGS
Surprised? Water planet, you said? In fact, there’s a lot of water in the large blue sphere depicted above. The largest sphere – representing all water on, in, and above Earth – would be about be about 860 miles (about 1,385 kilometers) in diameter. That’s in contrast to about 8,000 miles (about 12.5 thousand kilometers) for Earth.
Medium-sized sphere = Earth's liquid fresh water in groundwater,
swamp water, rivers, and lakes.
Smallest sphere = fresh water in all the lakes and rivers on the planet.
Or to put it another way, the largest blue sphere above holds 332,500,000 cubic miles (or 1,386,000,000) cubic kilometers (km3) water. We writers are always looking for analogies, but the best one I can think of to describe this amount is … well, it’s about as much as all the water on Earth.
See the smaller sphere over Kentucky? It represents Earth’s liquid fresh water in groundwater, swamp water, rivers, and lakes.
And do you see the even smaller (very tiny) bubble over Atlanta, Georgia? That one represents fresh water in all the lakes and rivers on the planet. USGS says that most of the water people and other earthly life require every day comes from these surface-water sources.
Bottom line: USGS says that all the water on Earth would fit into a sphere 860 miles (1,385 km) wide.
A 4 way lighting circuit has made many electricians scratch there heads at some point in time. The magic of the circuit is the 4 way switch. It is a specially manufactured light switch that enables you to put together a lighting circuit that will control a light from 3 different rooms or locations.
The wiring diagram above shows a typical 4 way switch installation.
Here is a schematic of the 4 way switch circuit from the first illustration. Start at switch 1 and follow the black (power), power travels through switch 1 through the black wire (travelers) over to switch 2 (4 way switch) through the 4 way switch, across the red traveler wire over to switch 3 then stops because switch 3 breaks the path. The light is off!
Now we have flipped switch 1, lets follow the power again. Power travels through switch 1 across the red traveler wire to switch 2 then through the 4 way switch to the black wire and over to switch 3, switch 3 passes the power to the black wire going to the light. The light is on!
So far we have been controlling the light from switch 1, now lets go into a different room and use switch 3. The above illustration shows that we have flipped switch 3, you can see that we have broken the power path and the light is now off.
Now lets go into another room and flip switch 2, if you follow the power you can see that the light has come back on. The 4 way switch is feeding power from red wire to red wire now and completing the circuit.
Now lets flip switch 1 again and follow the power. The power stops at switch 3 so the light is again off.
So there you go, we have turned the light on and off from every room. The circuit is really not that complicated, it is only a 3 way switch circuit with a 4 way switch put in the middle breaking the travelers.
Just remember to pay attention to the terminals on the light switches, the 3 ways will always have a common, NO, and NC, the common gets the power and the load. The 4 way is always 2 travelers on one side and 2 traveler on the other.
It seems like everyone has a blog these days, so it can be really hard to make your blog stand out. For every wildly successful blog with thousands of daily readers, there are dozens of blogs that are lucky enough to get a few clicks a week. If you are wondering why no one is reading your blog, these tips can tell you why and help you stand out from the crowd.
Hone in on Your Target Niche and Audience
The blogs with the highest number of visitors all share the same essential characteristics. They focus on
writing about a single theme of topics and they make sure to write content that is in line with their target audience's interests. Your blog is yours to do whatever you want with it, but if you fail to grasp the attention of an audience, how can you expect it to stand out. Making the blog all about what you want and not about what your potential readers want is one of the most common ways that people irritate potential visitors.
Say Things Worth Saying
The old adage, “content is king” is especially true when it comes to writing a blog. It is not enough just to put a lot of words down on the page and hope people will look at it. You have to focus on writing interesting, informative, and most importantly compelling content if you want to stand out. Establish yourself as an expert in your area and show your readers that you have a lot to teach them. If your content weren’t worth reading, why would visitors bother to stick around?
Have a Good Design
Your blog design doesn't have to be perfect, but it should be visually interesting, functional and free of flaws. You do not have to build your site from scratch, but you don't want to choose a very limited platform either. WordPress is one of the greatest blogging platforms for new and experienced bloggers alike because it is user-friendly and offers a lot of options for customization. You can purchase affordable premium WordPress themes to add a design flair and organization to your blog. Make sure to keep the design of your blog uncluttered. Keep the number of distracting ads to a minimum, and make sure the content is the most visible part of your blog. Readers aren't too picky when it comes to design, but if your website is hard to navigate or barely functional, readers will not want to stick around.
Find Ways To Bring in New Readers
Getting initial traffic to your blog is one of the hardest things to do as a blogger. If you aren't getting any visitors to begin with, you won't even have the chance to make your blog stand out from the competition. Focus on drawing new visitors to the site with a few simple marketing strategies, and then keep them coming back for more with your stellar content. Your marketing approaches don't have to be expensive or sophisticated, but you will have to work hard to build a steady stream of traffic.
Offer Something of Value
It might seem like a counterintuitive idea to give away your good ideas for free on your blog. However, the best blogs are the ones that offer something of value to the readers. If they don't get any benefit from reading the blog, then you aren't doing your job. Your blog posts should at least be either informative or entertaining, and ideally they would be both. You should strive to make a lasting impression on people with your blog post, by offering useful advice or information, or even by giving them a good laugh.
