1. Cryogenic and Superconducting Technologies for
3.2 MW Hybrid-Electric Aircraft Propulsion
T.J. Haugan1, G.Y. Panasyuk2
1Air Force Research Laboratory, AFRL/RQQM, Wright-Patterson AFB, OH
2UES Inc., Dayton OH
3.2 MW Aircraft deHavilland Dash 8
3.2 MW Drivetrains
70 kW Chevy-Volt Style Drivetrain, Siemens DA36 E-Star
de Havilland Bombadier Dash 8:
DHC series (Canada)
DHC-8-100
Capacity
37-39 passengers
Typical Payload
7511 lbs
Range
1174 miles
Motors
2 PW121
Motor Weight
1874 lbs
Max. Fuel Size
1003 U.S. gal
Max. Fuel Weight
6039 lbs
Maximum Weight
36661 lbs
70 kW Electric Motor
and Drivetrain
“Similar to General Motors' Chevy Volt drive train, the DA36 E-Star uses a serial hybrid electric drive train…”
- “Siemens scientists …are currently working on a new electric motor that is expected to be five times lighter than conventional drives. In two years, another aircraft is expected to be equipped with an ultra-light electric drive.”
3.2 MW Prius-Style Drivetrain
DHC-8-100B
Hybrid
Cu-Wire
Hybrid Cryo
3.2 MW Engine
(2 PW121)
1874 lb
1.83 MW Electric Motor/Generator
1010 lb*
101 lb
2.6 MW
Electric Motor
1439 lb*
144 lb
227 MJ Li Battery
413 lb**
Extra Machine Weight (w battery)
2862 lb
658 lb
Fuel Weight (Max.)
6039 lbs
3446 lb
5381 lb
(3.2 MW)
(1.8 MW)
(2.6 MW)
Pratt-Whitney PW110, 1.4 MW continuous
- PW121 Mass = 425 kg
- Power = MW continuous
- Power density = 3.77 kW/kg
prop
3 MW Components
3 MW Generators
(227 MJ)
Cu-Wire
1/2- Supercond
77K
Full- Supercondu ctor
@20K*
Weight Device (lb)
1554
753
132
Power Density (cont.)
4.1 kW/kg
8.8 kW/kg
50 kW/kg
Machine Efficiency (%) 95 97
99.97
Waste Heat (cont.)
150 kW
90 kW
0.9 kW
Waste Heat / Mass ( per hr)
540 MJ
324 MJ
3.3 MJ
Waste Heat / Mass (MJ/kg*h)
0.37
0.32
0.03
CryoCooler
3 MW (option)
66 lb cryo
? Non-cryo
238 lb*
Liquid 3 MW (option)
23.7 lbs/h
Liquid H2
Cryo 4x lighter
0.2 MW Cu-Wire
(Tesla Inc.)
GOTCHA: Weight
reduced > 10x
* Assume power density = 4 kW/kg
** Energy density = 400 Wh/kg
GOTCHA: Heat loss
reduced > 100x
Cryo 60% longer range
1-35 MW
½-Superconductor
(General Electric-MEPS)
1-30 MW Full-
Superconducting
(NASA-Glenn)
3.2 MW Chevy-Volt-Style Drivetrain
(1.8 MW)
(1.55 MW)
(3.2 MW)
(2.8 GJ)
DHC-8-100B
Hybrid
Cu-Wire*
Cryo
Combustion Engines
1874 lb (3.2 MW)
1054 lb
(1.8 MW)
1.55 MW Electric Motor/Generator
833 lb*
83 lb
3.2 MW Elec- Motor
1721 lb*
172 lb
Cooling ?
38 lb H2-liq/hr or
88 lb N2-liq/hr
Machine Weight
1,874 lb
3,608 lb
1,310 lb
Fuel Mix Max.
6,039 lb gas
772 lb gas
3,533 lb battery
5,831 lb battery
Machine+Fuel Max.
7,913 lb
Poweravg
1,174 miles gas
150 milesgas
69 mileselec**
126 mileselec **
Fuel Poweravg
(per 100 miles*passenger)
$6.51
$1.27
$1.14
GOTCHA: Risk factor
low for Cryo Machines
* Assume Turbo-Brayton cryocooler 30% efficient, and power density = 3 kw/Kg
*J. Felder, et al, NASA-Glenn, ISABE_ 2011_1340
3 MW Li-Batteries
Energy densities = 400 Wh/kg achieved !
Cryo 3x lighter
Rangeelec = [Range-Maxgas]/Fuel-Maxgas]*FuelBattery*[ƞelec/
Ƞgas]; where
Ƞ = drivetrain efificiency
* Assume power density = 4 kW/kg
** Battery energy density = 400 Wh/kg
- Electric Cu-wire drivetrain efficiency = 90%
(Tesla motors = 88%)
- Combustion efficiency = 29%
- HTS drivetrain efficiency = 99%
- Electric cost = $1.8 per gal equiv.
($0.054/kW-h, Dayton Sept 2013)
- JP-8 Fuel = $3.12 per gal (2012 avg)
Rangecryo-elec ~10% Rangegas
Fuel Cost 6x lower
Summary
The major components of 3.2 MW drivetrains were considered for both cryogenic and Cu-wire, however the associated power electronics and mechanical gearing were not estimated yet.
A Prius style drive-train is 4x lighter for cryogenic than Cu-wire.
A Chevy-volt style drive-train with cryogenic components is estimated to be 3x lighter, increasing the range for cruise in electric drive 2x and reducing fuel cost 3x.
Calculations
Cruise speed = 500 km/hr
Electric-drivetrain efficiency = 90% (Tesla Motors = 88%)
Power use = 22% of 3.2 MW
DISTRIBUTION A. Approved for public release. Distribution unlimited.