Ion drive for aircraft imminent.

In sci.physics krw wrote:
On Wed, 9 Nov 2016 00:13:29 -0000, wrote:

In sci.physics krw wrote:
On Tue, 8 Nov 2016 22:05:29 -0000, wrote:

In sci.physics mike wrote:
On 11/7/2016 11:13 PM, wrote:


Aircraft engines don't lift anything.


OK, how about, "Aircraft engines,
when properly fixtured,
can result in objects disengaging contact with the earth?"

How about the engine on fixed wing aircraft provides thrust to overcome
total drag to accelerate the aircraft to an airspeed sufficient to
provide enough lift from the wings to overcome the force of gravity?

How about the engine of a helicopter provides power to spin rotating
wings to a speed sufficient to develop enough lift to overcome the
force of gravity? For the purpose of this discussion assume that the
angle of attack of the rotor blades has been set appropriately.

There is more than one aircraft with a thrust to weight ratio greater
than unity, not to mention a rocket or two.

Yes, there certainly are but they are niche aircraft in the overall
scheme of things and an extremely small percentage of aircraft.

Maybe you'd like to include ornithopters in the discussion of engines
for flying machines.

Why not? The whole thread is already pretty silly.

From start to end...

Rockets are rockets.

https://en.wikipedia.org/wiki/Aircraft

Oh, Ion engines aren't be proposed for rockets, too? Never mind.

Where is the word "rocket" in the subject of this thread?


--
Jim Pennino

In sci.space.policy wrote:
How about the engine on fixed wing aircraft provides thrust to
overcome total drag to accelerate the aircraft to an airspeed
sufficient to provide enough lift from the wings to overcome the
force of gravity?

Where would you put the Harrier in that definition? Doesn't it have
the ability (albeit rather lightly loaded) to take-off vertically on
thrust from the engine alone?

rick jones
--
denial, anger, bargaining, depression, acceptance, rebirth...
where do you want to be today?
these opinions are mine, all mine; HPE might not want them anyway...
feel free to post, OR email to rick.jones2 in hpe.com but NOT BOTH...

In sci.physics Rick Jones wrote:
In sci.space.policy wrote:
How about the engine on fixed wing aircraft provides thrust to
overcome total drag to accelerate the aircraft to an airspeed
sufficient to provide enough lift from the wings to overcome the
force of gravity?

Where would you put the Harrier in that definition? Doesn't it have
the ability (albeit rather lightly loaded) to take-off vertically on
thrust from the engine alone?

rick jones

Yeah, it does, so now let's bring up all the other niche aircraft of
which there are very few starting with ornithopters.


--
Jim Pennino

In sci.physics Robert Clark wrote:
On 11/3/2016 9:00 AM, Robert Clark wrote:
Yes, that's a good example. Electric, battery-powered airplanes and
helicopters already exist.

Toys.


However, the key point is according to the
mathematics you can get even better power-to-thrust ratio with ionic
propulsion using ionizing wires at the nanoscale than helicopters
achieve.

what math ? got a url ?


As important as is the fact that you would no longer need heavy
transformers
to produce tens of thousands of volts, even more important is the high
thrust-to-power ratio you can get by only using low voltages.

How many times must you be told you do NOT need heavy transformers to
produce high voltages?

Camera flash units produce tens of thousands of volts.

....

A typical small aircraft engine produces about 140 kW, so at 500 V your
current is a bit under 300 A.

A typical small helicopter engine is about twice that size, so double
the current for a helicopter.

That means the conductors from the power supply must be huge and you
have to have hundreds, if not thousands, of emmitters to get the
individual currents down to levels that won't vaporize them.

Even if you mangaged to pull all that off, you now have a huge RFI
generator destroying all radio communication over a wide ares which
the FCC would never allow to be operated.



Camera flash units work by using electrical capacitors. So while they are
able to provide a large amount of power for their weight, they do this by
discharging all their stored energy in only a fraction of a second. This is
why despite intense research into "supercapacitors" they still have not been
able to replace chemical batteries for sustained, continuous power
production.

In regards, to the current carried by the nanowires, you would likely need
millions to billions of them to get the required thrust for a large craft.
This is because the thrust is lower for lower voltage. Having such a large
number of nanowires is a very well-known phenomenon in production VLSI
electronic devices though.

About the RFI, it may be because the voltage now required is only in the
hundreds of volts range rather than tens of thousands of volts, the RFI is
also significantly reduced. This is also something that needs to be tested


Bob Clark
--
----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

Nanotech: from air to space.
https://www.indiegogo.com/projects/n...ce/x/13319568/
----------------------------------------------------------------------------------------------------------------------------------

On 11/3/2016 9:00 AM, Robert Clark wrote:
Yes, that's a good example. Electric, battery-powered airplanes and
helicopters already exist.

Toys.


However, the key point is according to the
mathematics you can get even better power-to-thrust ratio with ionic
propulsion using ionizing wires at the nanoscale than helicopters
achieve.

what math ? got a url ?


As important as is the fact that you would no longer need heavy
transformers to produce tens of thousands of volts, even more important
is the high thrust-to-power ratio you can get by only using low voltages.

This page describes the operation of the "lifters":

Ionocraft.
3. Mechanism.
"A generalized one-dimensional treatment gives the equation:

F = I*d/k,
where
F is the resulting force, measured in dimension ML/T^2
I is the current flow of electric current, measured in dimension I.
d is the air gap distance, measured in dimension L.
k is the ion mobility coefficient of air, measured in dimension T^2 I/M
(Nominal value 2·10^−4 m^2/ Vs).

"In its basic form, the ionocraft is able to produce forces great enough
to lift about a gram of payload per watt,[6] so its use is restricted to
a tethered model. Ionocraft capable of payloads in the order of a few
grams usually need to be powered by power sources and high voltage
converters weighing a few kilograms, so although its simplistic design
makes it an excellent way to experiment with this technology, it is
unlikely that a fully autonomous ionocraft will be made with the present
construction methods. Further study in electrohydrodynamics, however,
show that different classes and construction methods of EHD thrusters
and hybrid technology (mixture with lighter-than-air techniques), can
achieve much higher payload or thrust-to-power ratios than those
achieved with the simple lifter design. Practical limits can be worked
out using well defined theory and calculations.[7] Thus, a fully
autonomous EHD thruster is theoretically possible."
https://en.wikipedia.org/wiki/Ionocraft#Mechanism

Since the power is P = I*V, amperage times voltage, the key thrust to
power ratio is F/P = d/kV. So if the air gap distance d remains the
same, reducing the voltage increases the thrust-power ratio. Then
theoretically IF the lifter is able to operate at hundreds of volts
instead tens of thousands of volts you could increase the thrust/power
ratio hundred(s) of times.

Note that you can't just arbitrarily use a low voltage. You need
sufficient voltage to initiate air ionization. Experiments have
confirmed that for wires at the nanoscale you do get the important
corona inception (air ionization) for voltages in the only 100's of
volts range. However, it is very important to note that when you reduce
the voltage and wire diameter the thrust is also reduced. Indeed to get
thrust sufficient for large scale objects you would then need to use
millions to billions of the nanowires.

Since the wires are only nanometers wide there is no problem in regards
to their fitting beneath a transport craft. But the large number of
wires required would be a consideration in regards to the wires corona
regions. You can't pack the wires too close together and maintain
maximum thrust since interaction between the separate corona's reduces
thrust. Among amateur experimenters that have built them, a lot of
experimentation has gone into the best geometry to maximize thrust. A
common arrangement is the triangular shape, with larger lifters
constructed using this basic shape as cells to build up to larger
devices.

The reason you don't have just have a bunch of parallel wires bunched
close together with the lifters is because of the corona region
interaction at small distance. Then there would have to be a significant
degree of experimentation to determine how close the nanowires could be
packed while maintaining maximum thrust.

In regards to the comparison of the thrust/power ratio of the lifters
compared to helicopters. This is a parameter known as power loading for
hovering transports. For helicopters it's commonly in the range of 6 to
10 lb/hp:

Helicopter Aerodynamics and Performance.
http://images.slideplayer.com/12/349...s/slide_51.jpg

This is about 3.6 to 6 grams-thrust/watt. The lifters currently made
using macroscale wires get about 1 gram-thrust per watt in thrust/power
ratio. So if the nanowire lifters really were able to manage a hundred
times better thrust/power ratio than current lifters, that would be a
major advance for hovering transport craft. Even if the nanowire lifters
only improve the thrust/power ratio over current lifters by a factor of
10, that would still be an improvement over current helicopters.

Bob Clark


A helicopter...a real one that is....can weigh as little as 1300 to 1600
pounds for a 2 place piston, like a Robinson R22 ( guessing the weight) to
a BK 117 like I fly which grosses out at 3200 Kgs to the huge Russian
machines that are up to over 100,000Kgs. The Mil V-12 is the largest I
believe. Whatever their weight they are sure to consume huge amounts of
fuel whatever they do.

1300 lb = 589,670 grams or about 589,670 watts required using your
conversion ratio,

assume you are using a max of 1 micro amp through your nano wires, then the
voltage needs to be W = V * I or 589,670 = V * 10^-6 or 58,967,000,000
Volts

unfortunatly, this amount of voltage breaks down air insulation for several
thousand feet, so the explosion and arc over will wipe out the wires.


I looked up the BK 117 helicopter:

MBB/Kawasaki BK 117.
4 Specifications (BK117 B-2).
"Max takeoff weight: 3,350 kg (7,385 lb)
Fuel capacity: 697 L (183 US Gallons, 153 Imp Gallons) internal fuel
Powerplant: 2 × Textron Lycoming LTS 101-750B-1 turboshaft, 442 kW (593 hp)
each"
https://en.wikipedia.org/wiki/MBB/Ka...28BK117_B-2.29

This is a thrust-to-power ratio of 7,385 lb/1,186 hp = 6.2 lb/hp, which is
in the range common for helicopters.

About the current needed to be carried by the nanowires, for a 1,300 lb, or
590 kg, helicopter, then IF the nanowires really do allow a 100 times better
thrust-to-power ratio than the lifters now, this will be a thrust/power
ratio of 100 grams-force/watt, 100 kg-force/kw.

Then this helicopter would need about 6 kw of power. If the voltage required
is only say 100 V because we are using nanowires, then 60 amps of current
would need to be carried. But remember we would distribute this over
millions to billions of the nanowires.

Also, note for this supposed 1,300 lb lifter, 6 kw of power is less than
only 8 hp, quite low for an air vehicle able to carry people.

Bob Clark

--
----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

Nanotech: from air to space.
https://www.indiegogo.com/projects/n...ce/x/13319568/
----------------------------------------------------------------------------------------------------------------------------------

EHANG 184 AAV -

http://www.ehang.com/ehang184

exists today.

Beamed power

http://lasermotive.com/markets/uav-power-links/

exists today and provides unlimited range point to point flight when used with electric fan propulsion.

A slightly more advanced system uses a Tail-Sitter design to increase speed from 100 mph to 450 mph whilst still providing point to point service and unlimited range

http://www.nasa.gov/topics/technolog...es/puffin.html

A solar power satellite in geosynch orbit that beams energy to users anywhere across the visible surface of the Earth, powers aircraft in flight, flying above local cloud cover. The aircraft uses electrical power to attain flight altitude, and the batteries are recharged in flight.

With VTOL capability, the tail-sitter, in horizontal flight mode, has the ability to climb at 4,000 ft/min. So it takes 10 minutes to climb to a service ceiling of 41,000 ft.

10 minutes - 75 mile range - climb to altitude for long range.
10 minutes - 75 mile range - descend from altitude for long range.

So, within 15 miles - climb and descent dominate. Beyond 150 miles, flight occurs at operating altitude (41,000 ft)

0:30 - 225 miles
1:00 - 450 miles
1:30 - 675 miles
2:00 - 900 miles
2:30 - 1125 miles
3:00 - 1350 miles
3:30 - 1575 miles
4:00 - 1800 miles
4:30 - 2025 miles
5:00 - 2250 miles

Cab service in NYC is $2.50 when you get in, and $0.50 for each 60 seconds - or 1/5th mile - whichever is greater.

http://www.nyc.gov/html/tlc/html/pas...cab_rate.shtml

Manhattan is 14 miles long and 2.3 miles wide. A service area centered on Manhattan's Upper West Side, near Verdi Square, with a 20 mile range - services ALL of Manhattan, out to Paramus, north to New Rochelle, and East to Flushing - it costs up to $102.50 to travel point to point in a matter of minutes throughout this range - serving over 12 million people!

Taxi Cabs

There were 12,000 cabs that generated $1.8 billion sales with 154 million trips in 2006.

http://www.nyc.gov/html/tlc/html/pas...cab_rate.shtml

With an average price of $12.50 per trip - trip lengths are 2 miles.

A VTOL system of the type described above, travelling at 100 mph takes no more than 12 minutes to travel 20 miles - and typically 2 minutes to travel 3 miles. Charging $5.00 per trip - and doing 5 trips an hour - requires 3,500 EHANG 184 type units to support the same number and lengths of trips as is now supplied by the present taxi fleet. 12,000 automated units, offered at $5 each, would transform transport and package delivery. People could order food from the finest restaurants in town, and have it delivered in minutes anywhere in the city and environs - for $5 - 12,000 units deliver $2..6 billion in sales per year with 523 million trips per year. $216,700 per year per unit. 43,300 trips per year - 5 trips per hour.

Subway

http://web.mta.info/nyct/facts/ffsubway.htm

1,763,000,000 riders per year by subway. That's 201,117 per hour. It costs $3 to enter the subway, with single use fares. Average speed is 17 mph. 40,223 EHANG 184 vehicles - travelling at 100 mph - has the potential to provide superior service. $5.28 billion per year $131,491 per vehicle year.

Manhattan's population is 1.63 million persons.

Greater New York City population: 23.7 million - within 65 miles of mid-town Manhattan - 595,803 vehicles provide the same level of service for all these people as the combined Taxi Subway system provides the people of Manhattan.

http://www.pcworld.com/article/30197...000-feet..html

http://drones.specout.com/l/328/EHang-184

The system costs $300,000 and generates 143 horsepower. (106 kW) - at $0.11 per kWh - it costs $2.33 per trip lasting 1/5th hour - With $12,000 service costs (4% acquisition costs) - there's another $0.27 - a total of $2.60 per trip. Each 60 second interval costs $0.20 for power and $0.02 for maintenance.

Provides quite a benefit to investors in the units.

On 11/13/2016 11:09 AM, Robert Clark wrote:

On 11/3/2016 9:00 AM, Robert Clark wrote:
Yes, that's a good example. Electric, battery-powered airplanes and
helicopters already exist.

Toys.


However, the key point is according to the
mathematics you can get even better power-to-thrust ratio with ionic
propulsion using ionizing wires at the nanoscale than helicopters
achieve.

what math ? got a url ?


As important as is the fact that you would no longer need heavy
transformers to produce tens of thousands of volts, even more important
is the high thrust-to-power ratio you can get by only using low
voltages.



A helicopter...a real one that is....can weigh as little as 1300 to
1600 pounds for a 2 place piston, like a Robinson R22 ( guessing the
weight) to a BK 117 like I fly which grosses out at 3200 Kgs to the
huge Russian machines that are up to over 100,000Kgs. The Mil V-12 is
the largest I believe. Whatever their weight they are sure to consume
huge amounts of fuel whatever they do.

1300 lb = 589,670 grams or about 589,670 watts required using your
conversion ratio,

assume you are using a max of 1 micro amp through your nano wires,
then the voltage needs to be W = V * I or 589,670 = V * 10^-6 or
58,967,000,000 Volts

unfortunatly, this amount of voltage breaks down air insulation for
several thousand feet, so the explosion and arc over will wipe out the
wires.


I looked up the BK 117 helicopter:

MBB/Kawasaki BK 117.
4 Specifications (BK117 B-2).
"Max takeoff weight: 3,350 kg (7,385 lb)
Fuel capacity: 697 L (183 US Gallons, 153 Imp Gallons) internal fuel
Powerplant: 2 × Textron Lycoming LTS 101-750B-1 turboshaft, 442 kW (593
hp) each"
https://en.wikipedia.org/wiki/MBB/Ka...28BK117_B-2.29


This is a thrust-to-power ratio of 7,385 lb/1,186 hp = 6.2 lb/hp, which
is in the range common for helicopters.

About the current needed to be carried by the nanowires, for a 1,300 lb,
or 590 kg, helicopter, then IF the nanowires really do allow a 100 times
better thrust-to-power ratio than the lifters now, this will be a
thrust/power ratio of 100 grams-force/watt, 100 kg-force/kw.

Then this helicopter would need about 6 kw of power.


you are too low by a factor of 100,

you make mistake it is not 100 gm/watt, but only 1gm per watt.

try again.



The *current* lifters get about 1 gm-force of thrust per watt of supplied
power, or 1 kg-force per kw. But the mathematics suggest using nanowires can
improve this by a factor of 100 to 100 kg-force per kw.

By the way, IF it is confirmed nanowires can result in the orders of
magnitude improvement, then a 1,300 lb hovering transport craft could be
powered by an engine the size of that on a push lawn mower.

This though would be a scenario where you're using a gasoline engine to
provide the power that is then converted to electricity to operate the
lifter drive.

Bob Clark

--
----------------------------------------------------------------------------------------------------------------------------------
Finally, nanotechnology can now fulfill its potential to revolutionize
21st-century technology, from the space elevator, to private, orbital
launchers, to 'flying cars'.
This crowdfunding campaign is to prove it:

Nanotech: from air to space.
https://www.indiegogo.com/projects/n...ce/x/13319568/
----------------------------------------------------------------------------------------------------------------------------------

"Robert Clark" wrote:

"Robert Clark" wrote:


I was using, lamentably, Windows Live Mail, for my newsreader. This
unfortunately does not allow you to put
a '' symbol before quoted responses. This makes it harder to understand
which part in the message is your response
and which is the previous post. So I was top-posting because my signature
line made it easier to distinguish the two.

However, after doing a web search and finding many people having the same
complaint about Windows Live Mail, I
found a work-around at the site
http://www.dusko-lolic.from.hr/wlmquote/.


Unfortunately I just realized the default version of this script does not
include your signature file.
So I'll have to customize it. More work.


Wouldn't it be simpler to just get a real newsreader? It's not like
they're all that hard to find.


Using the Windows newsreader mostly out of familiarity. What do you
recommend for a newsreader?


Windows doesn't have a 'newsreader', Bob. That's the problem.

What I'd recommend kind of depends on your tech level. There are
Windows versions of a lot of Unix newsreaders. Personally, I use
Agent and have for years. In the past I've used pine, tin, gnus, and
Thunderbird. Almost anything is better than the various Microsoft
Mail products bent to be newsreaders.

https://en.wikipedia.org/wiki/Compar...et_newsreaders


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw

wrote:


Aircraft engines don't lift anything.


Of course they do. It's that whole Lift/Drag thing. Remove the
engines and airplanes don't go up.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn

On 14/11/16 02:21, Fred J. McCall wrote:
wrote:


Aircraft engines don't lift anything.


Of course they do. It's that whole Lift/Drag thing. Remove the
engines and airplanes don't go up.

Except when they do, and that can be higher than commercial
airliners
https://en.wikipedia.org/wiki/Flight...record#Gliders

More seriously contrary to most people's belief, aircraft
engines aren't speed controls, they are climb/descend
controls. Steady-state speed is set by the attitude,
i.e. by the elevators.

Of course engines give more opportunities for varying
the attitude