[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 14:43:18 EDT 2016

Sorry 'bout that.

GA: general aviation

Cheating: just a matter of price. If it's really expensive to use these
materials maybe you don't want them for your electric aircraft. Like, why
aren't airliners 100% titanium? It's a great material, but expensive to buy
and machine

4 kW: just to point out you can do OK with avoiding the rare materials. I
worked on some 120 kW 32 kg motors (~4 kW/kg), that also did 1000 N*m
torque, without using anything particularly exotic. They were also direct
oil cooled, which the Siemens motors are.

On Tue, Jul 12, 2016 at 11:39 AM, Nancy Ouyang <nancy.ouyang at gmail.com>
wrote:

> wtf is GA
> why is it cheating to use crazy materials / power for first-in-class
> motor, &
> are you giving the example of 4 kw to contrast with their 5.2 kw
> techiniques, or to ...?
>
> if people write lengthier emails, it will help silly me understand what
> you are talking about <3
>
>
> ~~~
> my personal blog <http://www.orangenarwhals.com>, orangenarwhals
>
> On Tue, Jul 12, 2016 at 2:33 PM, damon vanderlind <damonvl at gmail.com>
> wrote:
>
>> 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
>>>>>>>
>>>>>>>    -
>>>>>>>
>>>>>>>
>>>>>
>>
>
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