[Cad] [motors, power ee, & evs] (Siemens) Electric aircraft: World-record (50kg:260 kW contiunuous) electric motor makes first flight. also, electric dirigibles from 1885?!

Tue Jul 12 14:33:41 EDT 2016

The batteries aren't that bad... people just need to stop caring if they
can fly 500 miles.

Siemens kind of cheats for their motors, though I think they are very nice.
They use hyperco 50 steel and really high switching frequencies. For now,
it prices the devices outside of GA even.  4 kw/kg can be built very cheap,
without rare materials and 1000 hours of wire edm time.

Cheers
--damon

On Tue, Jul 12, 2016 at 7:16 AM, Josh Vekhter <vekhterjr at gmail.com> wrote:

> Hmm, perhaps electric planes would actually be a reasonable application of
> that crazy aluminum galium thang the Marines are working on?
>
> Certianly makes more sense on an infrastructure level than fuel cell cars.
>
> Energy density of the fuel is supposed to be very good, idk anything about
> how much a 100 kw hydrogen fuel cell would weigh.
>
> Could always make hindenburg 2.0 :P.  Fuel could generate lift!
> On Jul 12, 2016 8:05 AM, "Lochie Ferrier" <lochieferrier at gmail.com> wrote:
>
>> Regardless of motor advances, batteries will still be primary issue due
>> to the mass fraction they need to take up. Even with a major improvement in
>> aero (co-flow airfoil
>> <http://www6.miami.edu/acfdlab/publications/AIAA-2015-0772.pdf>, or BLI
>> <http://web.mit.edu/drela/Public/N+3/Uranga2014_compressed.pdf>), the
>> L/D is still nowhere near what it needs to be for airliners, which are
>> majority of aviation emissions. This is where the whole Musk electric jet
>> <https://en.wikipedia.org/wiki/Musk_electric_jet> thing gets very dodgy,
>> or just beyond what we think is possible atm. To go cross country at 600
>> Wh/kg, you need a L/D of 30, for something that is *supersonic. *Play
>> around with the numbers <http://web.mit.edu/lochie/www/erange/main.html>,
>> and you'll hopefully see what I mean.
>>
>> There's very little way of getting around the fact that batteries are
>> approximately 100x heavier than kerosene on energy basis.
>>
>> On Tue, 12 Jul 2016 at 18:46 Nancy Ouyang <nancy.ouyang at gmail.com> wrote:
>>
>>> sweet pdf, though lol loweffort response :p yes ofc batteries
>>>
>>> I believe the PDF is 2012 (why oh why don't people put date writtens or
>>> at least year written in their documents)
>>>
>>> The few electric motors available toda*y for aircraft propulsion *have
>>>> a power output of *less than 100 kW*. Large electric motors are also
>>>> used in trains, ships and submarines, but here the mass is less important.
>>>> Today it seems to be possible to build electric motors having a *specific
>>>> mass of about 2 to 4 kW/kg*. This compares favorably with the specific
>>>> mass of larger turboshaft and turbofan engines at cruise power (see Figure
>>>> 13 and Figure 14). *Future developments* may extend the range of
>>>> electric motors to values of *up to 8 kW/kg*, but there is a strong
>>>> need for the development of lightweight electric motors, specifically
>>>> designed for application in aircraft.
>>>>
>>>
>>> so this gives context to why siemen's motor is cool.
>>>
>>> 260 kW / 50 kg =* 5.2 @ 260 kW* or roughly *orange* circle:
>>>
>>> [image: Inline image 1]
>>> pg 12
>>>
>>> *does anyone know what the comparable previous weight would be before
>>> this motor? *this one is 50kg &  if this is a lot less than before,
>>> it's just another notch in reducing weight to make weightspace for battery
>>> packs perhaps.
>>>
>>>
>>> Range sensitivities Equation 11 shows that in order to achieve maximum
>>>> range for a given aircraft mass A lightweight aircraft is more sensible to
>>>> a change in mass than a heavy aircraft.
>>>
>>>
>>> I love their *"let's think through how we'd make this work" thought
>>> experiment* section:
>>>
>>> Applying this simulation model to a specific aircraft allows determining
>>>> the possible performance and the technology improvements required to
>>>> achieve the desired results
>>>
>>>
>>> The range of the original aircraft with 32 passengers is about 1200 km.
>>>> With a reduced payload of 28 passengers the maximum range is approximately
>>>> 2200 km
>>>
>>>
>>> Using current (2012) technology this aircraft would reach a range of 202
>>>> km. The flight time would be about 40 minutes. Cruise speed would be about
>>>> 300 km/h. If an additional reserve of 30 minutes for holding at the
>>>> destination airport would have to be considered, the practical range would
>>>> drop to 50 km.
>>>
>>>
>>> The next modification would reduce the empty mass of the aircraft by
>>>> 20%. This would require introducing extreme lightweight design features
>>>
>>>
>>> This step improves the battery technology by doubling the mass specific
>>>> energy * E . *Such an improvement is quite well possible with future
>>>> development of Li-S battery systems within the next 15 years*. This
>>>> modification would double the range to 711 km so that it at least comes
>>>> into the order of the kerosene based aircraft. Nevertheless, there is still
>>>> a factor of 3 in range missing. In order to achieve the range of the
>>>> original aircraft, the battery technology would have to be improved by this
>>>> factor, i.e. a factor of 6 compared to todays (2012) technology.
>>>
>>>
>>> Furthermore new infrastructure to replace and recharge the batteries on
>>>> each airport would be required to make such an aircraft feasible
>>>
>>>
>>> Comparing the payload-range characteristics of the baseline turboprop
>>>> aircraft and the battery powered electric aircraft shows that trading
>>>> payload for fuel respectively battery has a very beneficial effect in case
>>>> of kerosene because of its high specific energy
>>>
>>>
>>>> If, on the other hand, the final extremely modified aircraft 328-LBME2
>>>> would be equipped with a current turbo-prop engine, its fuel consumption
>>>> would be as low as 1.5 liters per passenger per 100 km, which is about half
>>>> that of the baseline aircraft.
>>>
>>>
>>>
>>> (This last stat is mostly due to how light and dragless the author's
>>> thought-experiment is, I think.)
>>>
>>> Thanks,
>>> --Nancy
>>>
>>> ~~~
>>> my personal blog <http://www.orangenarwhals.com>, orangenarwhals
>>>
>>> On Tue, Jul 12, 2016 at 2:48 AM, Lochie Ferrier <lochieferrier at gmail.com
>>> > wrote:
>>>
>>>> The batteries though. The batteries are what makes it super hard
>>>> <http://www.mh-aerotools.de/company/paper_14/MP-AVT-209-09.pdf>.
>>>>
>>>> On Tue, 12 Jul 2016 at 16:31 Nancy Ouyang <nancy.ouyang at gmail.com>
>>>> wrote:
>>>>
>>>>> www.siemens.com/press/electric-aircraft
>>>>>
>>>>> *"This is the first time that an electric aircraft in
>>>>>> the quarter-megawatt performance class has flown."*
>>>>>
>>>>>
>>>>> https://www.youtube.com/watch?v=fiu8TFnXYFY
>>>>>
>>>>> In a big leap for the electrification of aviation, an Extra Aircraft
>>>>>> aerobatic plane performed its maiden flight with an electric powertrain.
>>>>>> The crucial component was a world record motor from Siemens. Weighing a
>>>>>> mere 50 kilograms, the motor has an output of 260 kilowatts, resulting in
>>>>>> an unparalleled power-to-weight ratio.
>>>>>
>>>>>
>>>>> Datasheet:
>>>>> http://www.siemens.com/press/pool/de/feature/2015/corporate/2015-03-electromotor/factsheet-erstflug-weltrekordmotor-d.pdf
>>>>>
>>>>>
>>>>>
>>>>> https://transportevolved.com/2016/07/08/siemens-showcases-brand-new-electric-motor-thats-super-light-super-powerful-and-perfect-for-electric-airplanes/
>>>>>
>>>>>> Of course, electric motors have long been used in model planes, but
>>>>>> their use outside the 1:14th scale aeromodelling arena has been
>>>>>> somewhat limited due to the mechanics of making a sufficiently large,
>>>>>> powerful, & lightweight electric motor. And while we’ve seen some very
>>>>>> successful electric planes take to the sky, most have been custom-made,
>>>>>> super-lightweight affairs which while impressive, have yet to make their
>>>>>> mark on a wider scale.
>>>>>
>>>>>
>>>>> Many of the benefits of electric motive power for aircraft are ones
>>>>>> that any EV driver will be familiar with: quieter, lower maintenance,
>>>>>> greater efficiency. Benefits that are shared with the community too in this
>>>>>> case – as with increasing air travel areas around airports have become
>>>>>> increasingly polluted – both by noise and by noxious residues from burning
>>>>>> fossil fuels.
>>>>>>
>>>>>
>>>>>
>>>>>> But there are also other benefits that are deeply exciting for
>>>>>> aeronautical engineers and pilots.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>> Unlike fossil fuel powered engines, electric motors really don’t care
>>>>>> which way is up. They operate the same upside-down as they do the right way
>>>>>> up — they don’t stall and fuss with fuelling issues when you turn them
>>>>>> over. They also perform the same at 40,000 feet as they do at 4 feet.
>>>>>> Traditional engines require complex mixture and timing adjustments to keep
>>>>>> them performing well in the thin atmosphere in which they spend much of
>>>>>> their lives.
>>>>>
>>>>>
>>>>> about the airplane,
>>>>>
>>>>>> Based on a thoroughly modern, but not deeply exceptional structure –
>>>>>> with a mixture of a steel fuselage and carbon fibre wings, the Extra is
>>>>>> itself a popular aerobatic model
>>>>>
>>>>>
>>>>>
>>>>>> The Extra 330LE, which weighs nearly 1,000 kilograms, serves as a
>>>>>> flying test bed for the new propulsion system. As an aerobatic airplane,
>>>>>> it's particularly well suited for taking the components to their limits,
>>>>>> testing them and enhancing their design.
>>>>>
>>>>>
>>>>> the future
>>>>>
>>>>>> Electric drives are scalable, and Siemens and Airbus will be using
>>>>>> the record-setting motor as a basis for developing regional airliners
>>>>>> powered by hybrid-electric propulsion systems. "By 2030, we expect to see
>>>>>> initial aircraft with up to 100 passengers and a range of around 1,000
>>>>>> kilometers," explained Anton.
>>>>>
>>>>>
>>>>>
>>>>> I love this anecdote about intelligent analysis tools in CAD. (*hi
>>>>> cad-discuss, that's why you're cc'd :]* )
>>>>>
>>>>> The end-shield for the motor, for example, was analyzed using a *software
>>>>>> package* that divided the component into over 100,000 elements, each
>>>>>> of which was individually further stress-analyzed and subject to*
>>>>>> iterative improvement loops.* Eventually, the custom software spat
>>>>>> out a filigree structure that weighs 4.9kg instead of the 10.5kg from the
>>>>>> previous design.
>>>>>
>>>>>
>>>>> more about the motor
>>>>> http://phys.org/news/2015-04-world-record-electric-motor-aircraft.html
>>>>>
>>>>> Siemens researchers have developed a new type of electric motor that,
>>>>>> with a weight of just 50 kilograms, delivers a* continuous output of
>>>>>> about 260 kilowatts – five times more than comparable drive systems.*
>>>>>> The motor has been *specially designed* for use in aircraft. Thanks
>>>>>> to its record-setting power-to-weight ratio, larger aircraft with *takeoff
>>>>>> weights of up to two tons* will now be able to* use electric drives
>>>>>> for the first time.*
>>>>>>
>>>>>
>>>>>
>>>>>> New simulation techniques and sophisticated lightweight construction
>>>>>> enabled the drive system to achieve a unique weight-to-performance ratio of
>>>>>> five kilowatts (kW) per kilogram (kg). *The electric motors of
>>>>>> comparable strength that are used in industrial applications deliver less
>>>>>> than one kW per kg. The performance of the drive systems used in electric
>>>>>> vehicles is about two kW per kg.* Since the new motor delivers its
>>>>>> record-setting performance at rotational speeds of just* 2,500
>>>>>> revolutions per minute, it can drive propellers directly, without the use
>>>>>> of a transmission.*
>>>>>>
>>>>>> In the next step, the Siemens researchers will boost output further.
>>>>>> "We're convinced that the use of hybrid-electric drives in regional
>>>>>> airliners with 50 to 100 passengers is a real medium-term possibility,"
>>>>>> said Anton.
>>>>>
>>>>>
>>>>>
>>>>> this might be what the motor looks like? not sure
>>>>> https://youtu.be/j3cNLsN-eCM?t=31s
>>>>> [image: Inline image 1]
>>>>>
>>>>>
>>>>>
>>>>> about the Siemens and electric dirigibles (?!)
>>>>>
>>>>>>
>>>>>
>>>>> Siemens current motor is sufficient to power a small 4-seater aircraft
>>>>>> by itself. Indeed, it would be “quite racy” suggest Siemens in that
>>>>>> application. And Siemens is keen to point out that the motor is *nearing
>>>>>> the power requirements for small regional airliners. *Of course if
>>>>>> anyone would know about aeronautical electric motors it really ought to be
>>>>>> Siemens, given that it was its electric motor that (back in 1881) powered
>>>>>> the *first electric dirigible*
>>>>>> <https://archive.org/details/lesballonsdirig00tissgoog>*.*
>>>>>
>>>>>
>>>>> Also check out this amazing scan of an* 1885 book about electric
>>>>> dirigibles*. (archive.org's ebook software is on-point!)
>>>>> https://archive.org/details/lesballonsdirig00tissgoog
>>>>>
>>>>>> Dirigibles: application of electricity to air navigation
>>>>>
>>>>> by Gaston Tissandier
>>>>>> Published 1885
>>>>>> Book digitized by Google from the library of the University of
>>>>>> Michigan and uploaded to the Internet Archive by user tpb.
>>>>>
>>>>>
>>>>>
>>>>> Thanks,
>>>>> --Nancy
>>>>>
>>>>>    -
>>>>>
>>>>>
>>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.mit.edu/pipermail/cad-rg/attachments/20160712/a6010866/attachment-0001.html
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 666317 bytes
Desc: not available
Url : http://mailman.mit.edu/pipermail/cad-rg/attachments/20160712/a6010866/attachment-0002.png
-------------- next part --------------
A non-text attachment was scrubbed...
Name: powerweightratio_electricairplanes_graph.png
Type: image/png
Size: 50999 bytes
Desc: not available
Url : http://mailman.mit.edu/pipermail/cad-rg/attachments/20160712/a6010866/attachment-0003.png