Wuhan Plasma Jets

[Guest]

 

Something  good has come out of Wuhan. Superb concept that hopefully works well. Let’s hope there is an airline industry left to adopt it.

 

For those that want to watch a video on the subject, this is from the excellent Fully Charged Show

 

 

And from Bloomberg - https://www.bloomberg.com/news/articles/2020-05-08/emission-free-flying-a-step-closer-with-chinese-plasma-thruster

 

Quote

Chinese scientists said they developed a plasma-thruster prototype that might one day lessen the aviation industry’s reliance on fossil fuel, bringing air travel free of carbon emissions a step closer to reality.
 

We’ve seen plasma thrusters before, but unlike those predecessors this one uses just air and electricity so no need for fossil fuels.

 

Quote

The device, built by a team from the Institute of Technological Sciences at Wuhan University, uses only air and electricity to generate propulsion with an efficiency comparable to a commercial jet engine under laboratory conditions. The team used the technology to lift a 1 kilogram (2.2 pound) steel ball over a quartz tube with a diameter of 24 millimeters (1 inch), it said in a paper published on Tuesday

Only under lab conditions at the moment, but very promising if it can be scaled up and efficient at that size.

 

[rcmaehl]

But does it 

SCALE?

[Guest]

13 minutes ago, rcmaehl said:

But does it 

SCALE?

Let’s hope, as it is a really cool concept.

 

What will be most interesting is how much energy needs to go in to produce the plasma, and with size And power how does the energy curve scale. 

[thorhammerz]

1 hour ago, Phill104 said:

Only under lab conditions at the moment, but very promising if it can be scaled up and efficient at that size

Looking forward to it in the 2050's. And that's assuming the technology can uh... migrate out of China before the iron curtain descends across the Pacific .

[mr moose]

If it's anything like my Chinese plasma cutter then NO THANKS!.  I'm already shit scared of flying, the last thing I need is to worry that the circuit breaker  will trip or the ceramic retainer breaks mid flight.   

[S w a t s o n]

2 minutes ago, huilun02 said:

Just electricity huh?

So with the battery power required to complete a trip, will the plane be able to take off at all?

This tech is useless until next generation solid state batteries exist for airplanes.

[mr moose]

17 minutes ago, huilun02 said:

Just electricity huh?

So with the battery power required to complete a trip, will the plane be able to take off at all?

Maybe, most things scale,  if you can have drones fly for half an hour on a charge using conventional motors then the Power density of batteries isn't the key issue,  it's energy efficiency in the engine that is.    Batteries are something like 2 orders of magnitude lower in energy density than regular fuel, however electric motors are significantly more efficient than combustion.  If the plasma thruster becomes more efficient than a jet engine (even a ICE with propeller), then batteries are the secondary issue to long flights.

 

Buuuuuuut, we'll have to wait for more info from this tech to be able to better know.

 

 

[Dabombinable]

So similar principles to an Ion thruster (or that ultra lightweight ion powered model plane)?

[RejZoR]

Cars need over half a ton of batteries to get somewhat similar range that an inefficient ICE can do with a 50 liter tank (lets say it's 50kg if we take water as a metric). Spot the difference? There is no way you can use any of this in aviation where weight is literally everything. I mean, 747 has a max takeoff weight of 378 tons. Each of its engines outputs up to 250 kN of thrust and as they come with 2 of them, that's up to 500kN of thrust. Basically this can move around 500 tons under most ideal conditions. Fuel tanks on 747 have around 190 tons of fuel. That's basically half the max weight in fuel alone and that's from jet fuel energy density. To store that kind of amount of energy in any battery storage we have today you'd have to carry basically 10x that if we use car metrics (500kg batteries vs 50kg fuel tank). Good luck trying to make a 3000 tons airplane airborne with any kind of thrusters. Not even Saturn V, one of most powerful space rockets has such weight (which maxes at 2300 tons and it's basically all fuel).

 

You can't compare toy plastic drones with something that actually has to carry more than its own weight. Those plastic drones work because that's somewhat the sweetspot of weight and thrust capacity for batteries. It's impossible to scale that to something like a 747.

 

While it's a cool invention for sure, it won't be usable for many more decades. Basically no battery tech will ever do it. We have to invent a portable reactor that will actually generate electricity onboard at sufficient rate and make these thrusters generate enough force to lift the weight of something like 747 using said reactor for power source. There is no way around that really.

[Guest]

20 minutes ago, RejZoR said:

Cars need over half a ton of batteries to get somewhat similar range that an inefficient ICE can do with a 50 liter tank (lets say it's 50kg if we take water as a metric). Spot the difference? There is no way you can use any of this in aviation where weight is literally everything. I mean, 747 has a max takeoff weight of 378 tons. Each of its engines outputs up to 250 kN of thrust and as they come with 2 of them, that's up to 500kN of thrust. Basically this can move around 500 tons under most ideal conditions. Fuel tanks on 747 have around 190 tons of fuel. That's basically half the max weight in fuel alone and that's from jet fuel energy density. To store that kind of amount of energy in any battery storage we have today you'd have to carry basically 10x that if we use car metrics (500kg batteries vs 50kg fuel tank). Good luck trying to make a 3000 tons airplane airborne with any kind of thrusters. Not even Saturn V, one of most powerful space rockets has such weight (which maxes at 2300 tons and it's basically all fuel).

 

You can't compare toy plastic drones with something that actually has to carry more than its own weight. Those plastic drones work because that's somewhat the sweetspot of weight and thrust capacity for batteries. It's impossible to scale that to something like a 747.

 

While it's a cool invention for sure, it won't be usable for many more decades. Basically no battery tech will ever do it. We have to invent a portable reactor that will actually generate electricity onboard at sufficient rate and make these thrusters generate enough force to lift the weight of something like 747 using said reactor for power source. There is no way around that really.

Comparing to cars is very difficult. While the current weight of batteries is large, when you look at many of them a lot of that weight is the liquid cooling. Not true in all cases, such as the Leaf or the new Lexus mentioned in the video above, but almost all other EVs have quite a substantial weight in cooling. What they gain in batteries they often loose in drive components such as engine, gearbox etc. What we also have to remember is that battery energy density  is increasing massively. Just 10 years ago a Renault Zoe had a paltry 22kwh, now in less space and lower weight it is 54kwh. With recent advances in solid state battery technology we could see that double very quickly. 
 

while I agree, it is a long way off, Airbus and Boeing are already demonstrating small electric planes. Airbus have been open and said electric planes will be their future. Take a look at the E-Fan X for instance. Yes, we are still a way off but it would be wrong to write off new tech like this so easily.

[RejZoR]

The thing is, cars are on the road. You just have to push them even if they weight almost 3 tons. You don't have that luxury in the sky...

[AlexGoesHigh]

yeah, the energy density of batteries is far away to being comparable to jet fuel, battery tech needs dramatically improve to use this, though it might be more feasible with today's battery tech on small short range drones.

[Guest]

46 minutes ago, AlexGoesHigh said:

yeah, the energy density of batteries is far away to being comparable to jet fuel, battery tech needs dramatically improve to use this, though it might be more feasible with today's battery tech on small short range drones.

There are already EV planes carrying passengers, and mainly trainee pilots in many countries. These are short range, light aircraft I grant you, but they are very successful. 

 

Airbus say the energy density of batteries will need to be about 30times what we have now to power an A320 for 1/4 of the current flight range, but would cost about 1/8th to run. So we do have a long way to go, but the advantages are clear to be seen. We may see hybrid planes in the shorter term.

[Guest]

42 minutes ago, RejZoR said:

The thing is, cars are on the road. You just have to push them even if they weight almost 3 tons. You don't have that luxury in the sky...

You could say the same about current jet planes. They actually use more fuel on the ground than at cruising altitude. It is the getting up there in the first place that is the biggest struggle. What could happen is a hybrid system where fuel generates the electricity for take off then batteries power cruising flight with fuel available for emergency use. That is probably quite feasible in a few years time. I do agree, fossil fuels will be with us for some time, but this kind of innovation brings us another step nearer.

[Master Disaster]

Just in case...

 

https://en.wikipedia.org/wiki/Energy_density#Tables_of_energy_content

 

Jet Fuel has an Energy Density of 43MJ/Kg

Batteries have 9MJ/Kg

 

The two things are not even in the same area code.

[Master Disaster]

10 minutes ago, Phill104 said:

You could say the same about current jet planes. They actually use more fuel on the ground than at cruising altitude. It is the getting up there in the first place that is the biggest struggle. What could happen is a hybrid system where fuel generates the electricity for take off then batteries power cruising flight with fuel available for emergency use. That is probably quite feasible in a few years time. I do agree, fossil fuels will be with us for some time, but this kind of innovation brings us another step nearer.

The issue here in current jet engines are an established technology with a proven track record.

 

It was Jeremy Clarkson who said "If you walked into a government safety panel today and suggested that everyone on earth should drive around in a metal box that does 150mph and that contains another box filled with a highly flammable liquid to use as a fuel you'd be laughed out of the room".

 

Convincing safety boards its safe will be a hard sell, convincing the industry to change will be even harder but convincing passengers these things aren't going to fall from the sky will be nigh on impossible.

 

Also to quote Mr Clarkson, "Electric engines are little more than a transfer of the climate change problem from the roads to the power stations as the vast majority of the electricity we generate still comes from burning fossil fuels".

[Egg-Roll]

The tech sounds nice and all however it's likely never going to get out of the lab, if it does that would be great, but personally sitting under fuel on a plane is scary enough, thinking you are going to be taking off with plasma possibly along side with said fuel. I would like to live thanks. Plasma is cool but there is a reason why no one has successfully used it on terrestrial aircrafts, less one nut job in Area 51 who may or may not exists

 

The team said its method differs from other types of plasma jet thrusters in that it compresses and ionizes air instead of xenon, argon, or hydrogen as used by spacecraft. The team is working on improving the efficiency of its device.

 

2 hours ago, Master Disaster said:

Also to quote Mr Clarkson, "Electric engines are little more than a transfer of the climate change problem from the roads to the power stations as the vast majority of the electricity we generate still comes from burning fossil fuels".

If I remember correctly a electric car running off of coal is still better for the environment than a gas powered one, not sure about hybrids in that case but since most don't drive hybrids yet that isn't much of a argument... Also that statement can be false depending where you live even in the USA, a great example is Norway, or if one lives near Hoover Dam. Also if that said vehicle spends most of its time in stop/go traffic unlike gas powered vehicles it can stretch its emissions from said source over longer distances with regenerative braking. EV's are less efficient (in terms) on highways, but are still in terms of emissions still cleaner than any gas vehicle on the planet, cost wise well that depends on where you live more than anything.

 

Also Clarkson isn't the best person to quote for EVs... While I like the guy he does what is needed to make money, and his form of making money is threw media.
https://www.theguardian.com/media/2013/mar/05/top-gear-tesla-jeremy-clarkson Personally I think Tesla went threw that all wrong, should have tried slander instead(Edit: oops same thing lol...), there is more information about that situation and I think it was the initiation of teslas data collection from review cars if a bad review with false claims happen again.

 

 

Quote

Something  good has come out of Wuhan

Could you actually remove this part, because it's offensive to those who are victim who live there by something that can (and has, H1N1) happen anywhere, not to mention false as I'm sure plenty of good has come from there before the virus. Also I don't blame China or Wuhan for the current state of the planet or the release of the virus but all the government bodies who refused to act sooner when they had a chance to halt it.

[Bombastinator]

A jet engine in only the loosest sense.  Most “jet engines” on commercial airliners are turbofans. It’s why there are blades on the front.    It’s more like a scramjet or a military jet afterburner.  Comparing it to commercial jet engines is potentially very misleading.  Lack of moving parts is cute.  

[Guest]

2 hours ago, Master Disaster said:

.

 

Also to quote Mr Clarkson, "Electric engines are little more than a transfer of the climate change problem from the roads to the power stations as the vast majority of the electricity we generate still comes from burning fossil fuels".

While I do enjoy Mr C, he does spout a bit at times.

 

In some very loose ways he is partly correct, but only in the sense that the fossil fuel companies spin would dictate. Most measurements for batteries vs fossil fuel are measured very differently. For ICE cars they go purely on fuel tank to miles. For some reason, for an EV they take into account the whole journey from generation to miles and always pick the dirtiest fuel, coal. If you take oil, it needs to be pumped many miles by massive electric pumps, broken down and refined using masses of electricity and more pumps to move it around. Driven in a diesel lorry to each site and pumped into tanks, then using more electricity to pump it into your car, which is at best on the 20s% efficient. An EV can be run on electricity generation from wind or solar or nuclear, far better than fossil fuels. It then goes into a car that is often over 80% efficient. Clarkson chooses to ignore all that because his heart is in petrol, nowt wrong with that.

[Guest]

2 hours ago, Master Disaster said:

Just in case...

 

https://en.wikipedia.org/wiki/Energy_density#Tables_of_energy_content

 

Jet Fuel has an Energy Density of 43MJ/Kg

Batteries have 9MJ/Kg

 

The two things are not even in the same area code.

Why would we have to use batteries? That was the first thing someone jumped one here but the article does not mention that, just that is is pure electricity propulsion. Hydrogen fuel cells may be a good candidate 

[Bombastinator]

20 minutes ago, Phill104 said:

Why would we have to use batteries? That was the first thing someone jumped one here but the article does not mention that, just that is is pure electricity propulsion. Hydrogen fuel cells may be a good candidate 

It’s still an energy density issue.  Current energy density of electric systems don’t even really support prop aircraft.  Not sure what the energy density of hydrogen systems are but it isn’t a whole ton better.  Current systems for working out military non fossil fuel aircraft involve synthetic fuel which hydrogen systems usually are in some way.  Either way it is sliced this system wants higher energy density than is currently available in batteries for use in aircraft.    Not sure that matters for purposes of research.

[Guest]

5 minutes ago, Nicholatian said:

Betting dollars to donuts they swiped this from some foreign military R&D and are repping it in the civilian space for kudos like it’s their own idea. China’s story told very well here.

Can we just stick to the tech and not make it an excuse to take cheap shots at china?

[Bombastinator]

5 minutes ago, Nicholatian said:

Betting dollars to donuts they swiped this from some foreign military R&D and are repping it in the civilian space for kudos like it’s their own idea. China’s story told very well here.

Wouldn’t need to be. It’s too simple.  This is “stick a plasma cutter in a tube and see what can be done”.

 

Not impossible of course.  China has a massive rep for stealing research rather than simply duplicating it. This is pretty basic stuff though. 

[RejZoR]

3 hours ago, Master Disaster said:

The issue here in current jet engines are an established technology with a proven track record.

 

It was Jeremy Clarkson who said "If you walked into a government safety panel today and suggested that everyone on earth should drive around in a metal box that does 150mph and that contains another box filled with a highly flammable liquid to use as a fuel you'd be laughed out of the room".

 

Convincing safety boards its safe will be a hard sell, convincing the industry to change will be even harder but convincing passengers these things aren't going to fall from the sky will be nigh on impossible.

 

Also to quote Mr Clarkson, "Electric engines are little more than a transfer of the climate change problem from the roads to the power stations as the vast majority of the electricity we generate still comes from burning fossil fuels".

Petrol/gas in cars really isn't that flammable. That's a BS myth propagated by Hollywood. You can literally soak a burning match into gasoline and it won't light it on fire. You can shoot gas tanks and it won't light on fire. Even with a tracer round you have to be lucky to hit it above the fuel where vapor is. Especially not if it's cold as there will be less fuel vapor around. And if it does start burning, you can extingusih it by cooling it or removing oxygen. When li-ion pack starts bursting flames you can just say goodbye to your car and there is no point in even calling fire department as they can't do anything except wait till the thing burns out on its own (li-ion cells are self sustaining and removing oxygen does nothing as well as cooling them by making them wet does nothing. Opposite, if you manage to make them wet inside, they can actually go out even more violently. They can only secure the area and that's it.

 

I had a presentation of fuel cells back in high school and that shit was the best thing possible and it never took off because li-ion cells became so cheap everyone rushed with them. And not even hydrogen fuel cells because hydrogen is hard to store, expensive to manufacture and really, the most of hydrogen that we do produce is actually obtained from fossil fuels. I'm talking ethanol/methanol fuel cells which do have some limitations, but with some effort I'm sure we could refine them. Best thing of alcohols is they are renewable source and are pretty much carbon neutral since they come from plants, they are liquid that could easily replace petrol in gas stations without any modifications to the supply chain and drivetrain would still be electric motor. So, we'd really be using the best possible options, best autonomy and range, super fast refueling without any stupid special chargers and within existing infrastructure. I guess EV lobby was too strong for batteries, just like petrol cars were back in the early days of cars where petrol won.

[Guest]

14 minutes ago, Bombastinator said:

It’s still an energy density issue.  Current energy density of electric systems don’t even really support prop aircraft.  Not sure what the energy density of hydrogen systems are but it isn’t a whole ton better.  Current systems for working out military non fossil fuel aircraft involve synthetic fuel which hydrogen systems usually are in some way.  Either way it is sliced this system wants higher energy density than is currently available in batteries for use in aircraft.    Not sure that matters for purposes of research.

A challenge indeed, but we do need to be looking at fossil fuel alternatives, it will run out.

 

just for the record Hydrogen has 33.33KWh/litre while Petrol and diesel 12KWh/litre. There are hurdles to overcome in generating hydrogen and generating electricity from it however.