It's similar, but not quite the same. In a motorjet, you basically have a piston-driven afterburner. The piston engine powers the compressor, the compressed air is combusted, and the exhaust is dumped out the back end. This is dumping the combustor, and using the compressed air to drive a pair of contrarotating turbines, in turn driving rotors.
Huh? By expanding and cooling, you mean decompressing. You're right back at the same point I described, too low of pressure ratio above atmospheric to do anything useful.
Turbines don't compress air. Turbines convert potential energy in the air into mechanical kinetic energy, reducing total pressure. Compressors add total pressure, and... well... compress things.
They run a compressor (air pump) to generate high pressure air, which they then feed through the turbines. The turbines are physically attached to the rotors on the same disk, so there is no need for drive shafts, transmissions, or anything. GE did the same thing with the two contrarotating pusher props on their UDF back in the 80s. The trouble is that you need to have those turbines extract enough power from the air to run the rotors. They're not physically large, so they can't produce a lot of torque. They're limited in RPM by being directly attached to the rotors. Low torque times low RPM equals low power, too little power to drive the rotors. GE got away with it on their UDF prototype because the fan and turbines were much closer in diameter, thus the turbine could run at a much more favorable RPM.
No. Ram air at 80mph will not produce any meaningful difference. You're talking about maybe one psi difference between forward facing and rearward facing at that speed, while your compressor is going to have to be producing several tens of psi to power that rotor. The only value of ram air on a car is that you're feeding the engine fresh, cool air, as opposed to air entering through the grille and heated by the radiator.
Without the "turbo" part either. "Turbo" implies a gas turbine engine. Turbojets are nothing more than a gas turbine. Turbofans have a gas turbine at their core. A turbocharger is a gas turbine wrapped around an internal combustion engine. This is a piston powered helicopter with a fluid dynamic transmission. It's merely different from the typical fluid dynamic transmission in that it is an open loop. Anyone in the automotive world will tell you a fluid dynamic transmission is lossy and inefficient. The only reason to plumb hot gasses around is because your engine design means you already have those hot gasses handily available. Oh, and they decided to supercharge it for some reason...
As for hot, fast gasses, they claim to be powering the rotor turbines with 100C compressed air, that's only that temperature after being heated up by the engine coolant and engine exhaust. At that temperature, there's not even enough energy in the flow to make that supercharger a net gain.
This would be a very interesting design if they actually used a gas turbine engine, rather than a piston engine (or realistically, an electric motor in their scale demo), as they would actually have enough exhaust flow to make it work. It would basically be the same thing GE did with their unducted fan, mating the contrarotating fan disks directly to a pair of contrarotating turbine disks, eliminating any deswirler or gearbox. The trouble is that these rotors have a strict top speed. Their tips cannot exceed the speed of sound, as doing so would cause all kinds of noise and vibrational issues on the helicopter. The scale difference between the rotor and the turbine means that means you're going to be running at a painfully low RPM, which is exactly why no one has done this commercially yet. It's really tough to get a turbine running that slowly, efficiently, and with significant power output.
According to the article, the air is compressed, then heated by the engine's cooling system, then mixed with exhaust gasses, and the resultant flow into the turbine is only 100C? Something doesn't seem right here. That temperature difference implies such a low boost that it won't even operate effectively as a supercharger, much less provide anything like enough power to those turbines. There's a reason gasoline engines with worthwhile turbochargers and superchargers all have intercoolers, and that's because compressing air makes it really damn hot.
So if I understand this correctly, by increasing the surface area of the electrodes, you increase storage density. We already knew that.
We did? I thought increasing the surface area of the electrodes increased the reaction rate, and thus the instantaneous power output. Energy capacity was increased by having more reagent.
because its not hard to see how a device used to read your brain signals could be modified to INSERT them too
Yes. Yes, it really is. This isn't the computer reading your mind, so much as it is your mind learning how to talk to the computer. There is a steep learning curve as your mind rewires itself to be able to produce the kinds of signals the EEG is set up to trigger off of. There is no way this could operate in reverse with our current level of technology and understanding.
You're thinking about this the wrong way. Most of these systems are like training your brain how to walk again after a serious trauma. You just hook up electrodes to a patch of cortex and come up with some unique brain pattern that you will use as a trigger for a certain task. You program the computer to respond to that pattern, providing a feedback response. Using the feedback, you train your brain to more accurately produce that pattern, while you simultaneously tune the computer to pick up on the evolving pattern. These are not the kinds of things you just plug in and go, they take considerable time and effort to make work for each individual.
No one cares about sovereign territory. It all comes down to taxes. The government does nothing if not collect taxes. During Apollo 13, Jack Swigert was allowed a 60-day extension on filing his income taxes as the IRS had determined he was out of the country when they were due.
My "anal retentive ass" side only came out when tristes_tigres decided to be obtuse and insist the vehicle was wheel driven, as opposed to propeller driven, after being told otherwise repeatedly.
Goodness me, we'd better tell the aviation industry that it's incorrect to call a propellor a propellor when the throttle has been shut or the engine completely killed/died!
If you're actually connecting that propeller to a generator, then yes, it would be a turbine, however I'm not aware of anything that actually does that. There are often pop-out ram air turbines for that specific purpose, either to power weapons and other equipment on hardpoints, or as emergency backup power should your APU or batteries fail. In the case of a propeller, you would call them a retarder, and you typically feather your props to prevent that from happening.
Every prop can function as a turbine and every turbine as a prop.
Perhaps, but not efficiently. You can extract a whole lot more energy out of the flow with a turbine than you can put into the flow with a propeller. As such, a propeller is going to have mild camber allowing modest operation inverted as a turbine, but a turbine is going to be aggressively cambered and would immediately stall were you to attempt to use it as a propeller.
Any commercial airliner flying that low will be taking off or landing, and as such their flight paths will be dictated by the orientation of the runway. The drone was clearly somewhere it shouldn't have been.
Major damage? Sure, but not fatal damage. The only way for an 80lb craft to cause likely fatal damage is to hit the cockpit and cause fatal damage to its pilots. Wings are tough. You have two engines. You have redundant control systems. The plane would be a total loss, but chances are good there would be enough left intact after the collision to land.
That depends on how the system is implemented. An electro-optical array capable of spotting another jet half a mile out would give sufficient time to dodge.
Regardless of your definition of terms, the point is you're wrong, and this propeller, behaving as a propeller that turns torque into lift, is being used to propel the car. The wheels in turn power the propeller. Were the vehicle operating as you say, then you would be correct that it would be unable to travel faster than the wind downstream.
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It's similar, but not quite the same. In a motorjet, you basically have a piston-driven afterburner. The piston engine powers the compressor, the compressed air is combusted, and the exhaust is dumped out the back end. This is dumping the combustor, and using the compressed air to drive a pair of contrarotating turbines, in turn driving rotors.
Huh? By expanding and cooling, you mean decompressing. You're right back at the same point I described, too low of pressure ratio above atmospheric to do anything useful.
Turbines don't compress air. Turbines convert potential energy in the air into mechanical kinetic energy, reducing total pressure. Compressors add total pressure, and... well... compress things.
They run a compressor (air pump) to generate high pressure air, which they then feed through the turbines. The turbines are physically attached to the rotors on the same disk, so there is no need for drive shafts, transmissions, or anything. GE did the same thing with the two contrarotating pusher props on their UDF back in the 80s. The trouble is that you need to have those turbines extract enough power from the air to run the rotors. They're not physically large, so they can't produce a lot of torque. They're limited in RPM by being directly attached to the rotors. Low torque times low RPM equals low power, too little power to drive the rotors. GE got away with it on their UDF prototype because the fan and turbines were much closer in diameter, thus the turbine could run at a much more favorable RPM.
No. Ram air at 80mph will not produce any meaningful difference. You're talking about maybe one psi difference between forward facing and rearward facing at that speed, while your compressor is going to have to be producing several tens of psi to power that rotor. The only value of ram air on a car is that you're feeding the engine fresh, cool air, as opposed to air entering through the grille and heated by the radiator.
Or rather... power = work / time....
Without the "turbo" part either. "Turbo" implies a gas turbine engine. Turbojets are nothing more than a gas turbine. Turbofans have a gas turbine at their core. A turbocharger is a gas turbine wrapped around an internal combustion engine. This is a piston powered helicopter with a fluid dynamic transmission. It's merely different from the typical fluid dynamic transmission in that it is an open loop. Anyone in the automotive world will tell you a fluid dynamic transmission is lossy and inefficient. The only reason to plumb hot gasses around is because your engine design means you already have those hot gasses handily available. Oh, and they decided to supercharge it for some reason...
As for hot, fast gasses, they claim to be powering the rotor turbines with 100C compressed air, that's only that temperature after being heated up by the engine coolant and engine exhaust. At that temperature, there's not even enough energy in the flow to make that supercharger a net gain.
This would be a very interesting design if they actually used a gas turbine engine, rather than a piston engine (or realistically, an electric motor in their scale demo), as they would actually have enough exhaust flow to make it work. It would basically be the same thing GE did with their unducted fan, mating the contrarotating fan disks directly to a pair of contrarotating turbine disks, eliminating any deswirler or gearbox. The trouble is that these rotors have a strict top speed. Their tips cannot exceed the speed of sound, as doing so would cause all kinds of noise and vibrational issues on the helicopter. The scale difference between the rotor and the turbine means that means you're going to be running at a painfully low RPM, which is exactly why no one has done this commercially yet. It's really tough to get a turbine running that slowly, efficiently, and with significant power output.
You've got that backwards. Work is power done over a period of time.
According to the article, the air is compressed, then heated by the engine's cooling system, then mixed with exhaust gasses, and the resultant flow into the turbine is only 100C? Something doesn't seem right here. That temperature difference implies such a low boost that it won't even operate effectively as a supercharger, much less provide anything like enough power to those turbines. There's a reason gasoline engines with worthwhile turbochargers and superchargers all have intercoolers, and that's because compressing air makes it really damn hot.
So if I understand this correctly, by increasing the surface area of the electrodes, you increase storage density. We already knew that.
We did? I thought increasing the surface area of the electrodes increased the reaction rate, and thus the instantaneous power output. Energy capacity was increased by having more reagent.
because its not hard to see how a device used to read your brain signals could be modified to INSERT them too
Yes. Yes, it really is. This isn't the computer reading your mind, so much as it is your mind learning how to talk to the computer. There is a steep learning curve as your mind rewires itself to be able to produce the kinds of signals the EEG is set up to trigger off of. There is no way this could operate in reverse with our current level of technology and understanding.
You know, you use your "mind" to control your hands, right?
You're thinking about this the wrong way. Most of these systems are like training your brain how to walk again after a serious trauma. You just hook up electrodes to a patch of cortex and come up with some unique brain pattern that you will use as a trigger for a certain task. You program the computer to respond to that pattern, providing a feedback response. Using the feedback, you train your brain to more accurately produce that pattern, while you simultaneously tune the computer to pick up on the evolving pattern. These are not the kinds of things you just plug in and go, they take considerable time and effort to make work for each individual.
No one cares about sovereign territory. It all comes down to taxes. The government does nothing if not collect taxes. During Apollo 13, Jack Swigert was allowed a 60-day extension on filing his income taxes as the IRS had determined he was out of the country when they were due.
My "anal retentive ass" side only came out when tristes_tigres decided to be obtuse and insist the vehicle was wheel driven, as opposed to propeller driven, after being told otherwise repeatedly.
There are experimental aircraft using blown flaps and similar devices to very nearly take off vertically.
That's silly. Most people buy Dreamboxes specifically so they don't have to pay a subscription.
Goodness me, we'd better tell the aviation industry that it's incorrect to call a propellor a propellor when the throttle has been shut or the engine completely killed/died!
If you're actually connecting that propeller to a generator, then yes, it would be a turbine, however I'm not aware of anything that actually does that. There are often pop-out ram air turbines for that specific purpose, either to power weapons and other equipment on hardpoints, or as emergency backup power should your APU or batteries fail. In the case of a propeller, you would call them a retarder, and you typically feather your props to prevent that from happening.
Every prop can function as a turbine and every turbine as a prop.
Perhaps, but not efficiently. You can extract a whole lot more energy out of the flow with a turbine than you can put into the flow with a propeller. As such, a propeller is going to have mild camber allowing modest operation inverted as a turbine, but a turbine is going to be aggressively cambered and would immediately stall were you to attempt to use it as a propeller.
Well there was Eagle Eye, and now Person of Interest.
No military aircraft operate under civilian traffic control.
Any commercial airliner flying that low will be taking off or landing, and as such their flight paths will be dictated by the orientation of the runway. The drone was clearly somewhere it shouldn't have been.
Major damage? Sure, but not fatal damage. The only way for an 80lb craft to cause likely fatal damage is to hit the cockpit and cause fatal damage to its pilots. Wings are tough. You have two engines. You have redundant control systems. The plane would be a total loss, but chances are good there would be enough left intact after the collision to land.
Thousands of years of recorded human history would tend to agree. That's just crazy.
That depends on how the system is implemented. An electro-optical array capable of spotting another jet half a mile out would give sufficient time to dodge.
You could say the attempt was so poor, it crashed and burned.
Regardless of your definition of terms, the point is you're wrong, and this propeller, behaving as a propeller that turns torque into lift, is being used to propel the car. The wheels in turn power the propeller. Were the vehicle operating as you say, then you would be correct that it would be unable to travel faster than the wind downstream.