[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 20:16:43 EDT 2016

Damon,
direct oil cooling on the motors you worked on - is the rotor floating in
oil and making viscous losses in the air gap?
or oil mist?

Nkirkby
On Jul 12, 2016 2:43 PM, "damon vanderlind" <damonvl at gmail.com> wrote:

> 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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