It seems to me that somewhere along the way NASA has changed from an operation mode where you had to prove that something was safe to proving that something is not safe.
When that fails, a copy of The Sims Hot Date expansion.
another form of circulation control
on
Fanwing Planes?
·
· Score: 2, Informative
It seems that this is another form of circulation control for airfoils. This has been done for high lift wings, stopped rotors, helicopter tail booms, etc, with varying levels of success. It's an interesting way of doing it. In stead of bleading off the engine to blow out small slots, use the exhaust of the propulsive device to energize the boundry layer. This way you can keep the flow attached to the upper surface far longer than on your basic airfoil. You'd need to do that since I don't see the front half of that wing producing much lift.
The problem with current state of engineering education is that there is an incredible amount of informations out there, and the universities are trying to cram at least the basics of what will keep you current into 4 years (along with all the other requirements). Therefore, something must be eliminated, which is usually the hands on courses. All the theory is important not from the "I can solve a math problem" point of view, but that it teaches you the limitations of the theory, which form the the foundation for all the sophisticated tools engineers use out in industry. But this comes at a loss of other skills only learned from hands on work. It's easy to design something that looks good on paper, but is next to impossible or impractical to build.
As a TA in several engineering courses I've seen students plug numbers in to formulas, and get answers that made no sense, but they were perfectly happy with them since they didn't understand what the numbers ment physically. One of the best grad courses I had blended theory and application, maybe that approach will help balance the theory-practicality problem, and address issues like interpretation of the results obtained through analytical models.
I can't agree with the no E-M interference statement. I can see there being less of it, but piezoelectric materials run on the concept of using a voltage differential to change the shape of the material. So you have to use electric current to produce the waving motion. I guess if the difference in EM fields is in orders of magnitude, than you can assume there is virtually no EM interference.
CNN is running a similar article, http://www.cnn.com/2001/TECH/ptech/11/26/intel.reu t/index.html
, but in it they claim that "Intel Corp. has devised a new structure for transistors -- the tiny switches that make up semiconductors..." That's a new one to me: semiconductors are made of transistors... I guess no one there proof reads, or more likely understands what they write about.
I understand perfectly what you're going through. I was in that sort of a situation, except I'm in engineering. What I wound up doing is examining what it was that really interested me to persue a degree in it. Once I did that, I found out what is out there in my field that my interests can be directly applied to and did everything that I could to get into that type of work. It worked for me.
Good luck.
It might be a poor name choice for the english speaking world, but it's not the first time bad name choices have been made for products sold in other countries (Chevy Nova). NeCoRo makes pretty good sense in Japanese, at least to me it does. I don't speak a lot of Japanese, but I do know that Neko means cat and in English c's are usually pronounced like k's in many other languages. So I can see the connection: cat-RObot.
An article in filmforce.com (http://filmforce.ign.com/matrix/articles/305472p1.html ) gives some info on how Warner Brothers is dealing with the character that Aaliyah played.
Pesonally, I think this guy (http://rocketguy.com) will kill himself first.:) A lot of money and some knowladge can definately go a long way towards that goal. Looking as some of the stuff he did is quite impressive, but it seems like he sees some new technology and wants to use it, i.e. his landing system. Airbags, balloons, parachutes and parafoils, all in one landing. I guess he never head of the "K.I.S.S." principle.
I agree that we need to write our representatives. The reason to be worried stems for the fact that the entertainment industry has the politicians in their back pockets. How else can DMCA be legal? How else can the recording industry tell us that we can't buy DVD's from other zones and watch them as often as we want? Well, you can but switch your DVD player zone a couple of times and you'll see what your freedom of speach amounts to (or in reality your freedom to watch something that was not illigally obtained.)
To me, these ant-based algorithms seem very similar to genetic algorithms in used in optimization problems: using some random solutions as a seed, modifying them (via trait swaping or deviations from solution, depending on the algoritm,) and looking at some function defining how good the solution is. I realize it's more complicated than that, but that seems to be the gist of it.
In both cases, (ant based and genetic algotithms) it amazes me how much we can still learn from everyday things that we see in nature. I'd love to see what else may be on the horizon.
The SCRAMJET projectile left the cannon at about 7810 ft/s. Since it traveled 260 ft in.03 seconds, that's an average speed of 8667 ft/s. So the SCRAMJET engine produced a significant acceleration. The significance of the test lies how the SCRAMJET operates. RAMJET engines take in supersonic air and decelearate it using shock waves to subsonic speeds, then adds fuel and ignites and expands producing a thrust. The air getting rammed down the intake keeps the expanding air from getting blown out the intake. SCRAMJETs on the other hand, don't decelarate the air to subsonic speeds. So the whole problem is that when you add fuel and ignite it, you want to control the whole process so that it occurs inside the engine, not get blown out the back and then finish burning and expanding. There it doesn't provide any thrust for you. There are also problems with stability of the whole process. So what little information that I have on this test, I would tend to think that it was used mainly to examine if you could burn the fuel inside the engine, thereby producing thrust. 0.03 seconds is not much time to examine stability.
As for drag, it's going to be pretty high, but it's not very significant compared to the thrust provided by the SCRAMJET.
Here is also a link to the DARPA news release (which doesn't really tell you anything.):)
http://www.darpa.mil/body/newsitems/scramjetfinal. doc
I see your point, but I can't completely agree with you. Morphing may be too strong a word to use for what will probably come out of this technology without some major breakthroughs in materials. Most people associate morphing with radical changes in geometry. More than likely it will be just small changes in airfoil thickness and camber or twist of the wings to change the angle of attack distribution across them. Or even more likely this will result in active damping technology to provide a smoother ride. Piezoceramics they're using can only produce very small changes in size, and you have to use all sorts of mechanical amplifiers to make those changes really noticable, but it's at the expense of actuation force, or distribute them over a large sturucture. If I remember correctly, these fiber-composites and other types of piezoactuators have been used in scaled helicopter rotors and they were able to provide just a few degrees change in twist over the entire rotor blade. Unfortunatley this doesn't scale up to a full rotor. So as you can see, you're not producing large changes but in terms of performance they can be significant if applied correctly.
The reason for the large wingspan is, in all likelyhood, to increase the wing's aspect ratio (span squared divided by wing area). For any given wing area, a higher aspect ratio results in a more efficient lifting surface or less drag for a given amount of lift. Sailplanes are designed with this in mind. In this case, it would improve the fuel economy.
Slashdot Mirror
It seems to me that somewhere along the way NASA has changed from an operation mode where you had to prove that something was safe to proving that something is not safe.
> Or what all geeks are in need of. A girlfriend.
When that fails, a copy of The Sims Hot Date expansion.
It seems that this is another form of circulation control for airfoils. This has been done for high lift wings, stopped rotors, helicopter tail booms, etc, with varying levels of success. It's an interesting way of doing it. In stead of bleading off the engine to blow out small slots, use the exhaust of the propulsive device to energize the boundry layer. This way you can keep the flow attached to the upper surface far longer than on your basic airfoil. You'd need to do that since I don't see the front half of that wing producing much lift.
The problem with current state of engineering education is that there is an incredible amount of informations out there, and the universities are trying to cram at least the basics of what will keep you current into 4 years (along with all the other requirements). Therefore, something must be eliminated, which is usually the hands on courses. All the theory is important not from the "I can solve a math problem" point of view, but that it teaches you the limitations of the theory, which form the the foundation for all the sophisticated tools engineers use out in industry. But this comes at a loss of other skills only learned from hands on work. It's easy to design something that looks good on paper, but is next to impossible or impractical to build.
As a TA in several engineering courses I've seen students plug numbers in to formulas, and get answers that made no sense, but they were perfectly happy with them since they didn't understand what the numbers ment physically. One of the best grad courses I had blended theory and application, maybe that approach will help balance the theory-practicality problem, and address issues like interpretation of the results obtained through analytical models.
I can't agree with the no E-M interference statement. I can see there being less of it, but piezoelectric materials run on the concept of using a voltage differential to change the shape of the material. So you have to use electric current to produce the waving motion. I guess if the difference in EM fields is in orders of magnitude, than you can assume there is virtually no EM interference.
CNN is running a similar article, http://www.cnn.com/2001/TECH/ptech/11/26/intel.reu t/index.html
, but in it they claim that "Intel Corp. has devised a new structure for transistors -- the tiny switches that make up semiconductors..." That's a new one to me: semiconductors are made of transistors... I guess no one there proof reads, or more likely understands what they write about.
I understand perfectly what you're going through. I was in that sort of a situation, except I'm in engineering. What I wound up doing is examining what it was that really interested me to persue a degree in it. Once I did that, I found out what is out there in my field that my interests can be directly applied to and did everything that I could to get into that type of work. It worked for me.
Good luck.
It might be a poor name choice for the english speaking world, but it's not the first time bad name choices have been made for products sold in other countries (Chevy Nova). NeCoRo makes pretty good sense in Japanese, at least to me it does. I don't speak a lot of Japanese, but I do know that Neko means cat and in English c's are usually pronounced like k's in many other languages. So I can see the connection: cat-RObot.
An article in filmforce.com (http://filmforce.ign.com/matrix/articles/305472p1 .html ) gives some info on how Warner Brothers is dealing with the character that Aaliyah played.
Pesonally, I think this guy (http://rocketguy.com) will kill himself first. :) A lot of money and some knowladge can definately go a long way towards that goal. Looking as some of the stuff he did is quite impressive, but it seems like he sees some new technology and wants to use it, i.e. his landing system. Airbags, balloons, parachutes and parafoils, all in one landing. I guess he never head of the "K.I.S.S." principle.
I agree that we need to write our representatives. The reason to be worried stems for the fact that the entertainment industry has the politicians in their back pockets. How else can DMCA be legal? How else can the recording industry tell us that we can't buy DVD's from other zones and watch them as often as we want? Well, you can but switch your DVD player zone a couple of times and you'll see what your freedom of speach amounts to (or in reality your freedom to watch something that was not illigally obtained.)
To me, these ant-based algorithms seem very similar to genetic algorithms in used in optimization problems: using some random solutions as a seed, modifying them (via trait swaping or deviations from solution, depending on the algoritm,) and looking at some function defining how good the solution is. I realize it's more complicated than that, but that seems to be the gist of it.
In both cases, (ant based and genetic algotithms) it amazes me how much we can still learn from everyday things that we see in nature. I'd love to see what else may be on the horizon.
The picture of Bill in the Wired.com article should be "Eeexcellent, Smithers. It's all going according to plan."
The SCRAMJET projectile left the cannon at about 7810 ft/s. Since it traveled 260 ft in .03 seconds, that's an average speed of 8667 ft/s. So the SCRAMJET engine produced a significant acceleration. The significance of the test lies how the SCRAMJET operates. RAMJET engines take in supersonic air and decelearate it using shock waves to subsonic speeds, then adds fuel and ignites and expands producing a thrust. The air getting rammed down the intake keeps the expanding air from getting blown out the intake. SCRAMJETs on the other hand, don't decelarate the air to subsonic speeds. So the whole problem is that when you add fuel and ignite it, you want to control the whole process so that it occurs inside the engine, not get blown out the back and then finish burning and expanding. There it doesn't provide any thrust for you. There are also problems with stability of the whole process. So what little information that I have on this test, I would tend to think that it was used mainly to examine if you could burn the fuel inside the engine, thereby producing thrust. 0.03 seconds is not much time to examine stability.
:)
. doc
As for drag, it's going to be pretty high, but it's not very significant compared to the thrust provided by the SCRAMJET.
Here is also a link to the DARPA news release (which doesn't really tell you anything.)
http://www.darpa.mil/body/newsitems/scramjetfinal
I see your point, but I can't completely agree with you. Morphing may be too strong a word to use for what will probably come out of this technology without some major breakthroughs in materials. Most people associate morphing with radical changes in geometry. More than likely it will be just small changes in airfoil thickness and camber or twist of the wings to change the angle of attack distribution across them. Or even more likely this will result in active damping technology to provide a smoother ride. Piezoceramics they're using can only produce very small changes in size, and you have to use all sorts of mechanical amplifiers to make those changes really noticable, but it's at the expense of actuation force, or distribute them over a large sturucture. If I remember correctly, these fiber-composites and other types of piezoactuators have been used in scaled helicopter rotors and they were able to provide just a few degrees change in twist over the entire rotor blade. Unfortunatley this doesn't scale up to a full rotor. So as you can see, you're not producing large changes but in terms of performance they can be significant if applied correctly.
The reason for the large wingspan is, in all likelyhood, to increase the wing's aspect ratio (span squared divided by wing area). For any given wing area, a higher aspect ratio results in a more efficient lifting surface or less drag for a given amount of lift. Sailplanes are designed with this in mind. In this case, it would improve the fuel economy.