Applied Research LaboratoryP. O. Box 30State College, PA 16804-0030

AUV Power and Endurance24 April 2002

ARL

Presented by:Dr. Thomas G. HughesHead, Energy Systems Division

Presented to:Fifth International SymposiumTechnology and the Mine Problem

21” Diameter 38” Diameter

26.5” Diameter

Representative AUVs

Volume To Surface Area Ratio

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

2.00

21 36 48 60 72 84 96

UUV DIAMETER [IN]

CU

BIC

FE

ET

PE

R S

QU

AR

E F

OO

T

P

d 7 d d

Representative Propulsors

Inlet GuideVane (IGV)

Weed Guard

Control Fin

Rotor

Shroud

TVPJ

Motor

Motor RingMounts

PCIU(7x7x7)

NC Interfacennnector andlkhead (notpictured)

Aft Hull InletGuide Vanes

StatorShroud

ControlFin

“A” Cable HullConnector

Actuator

Drive Train WithShaft, Bearingsand Seawater Seal

LoadButton

Rotor

Fwd Hull

Power vs Speed (38" dia. UUV)

0

2

4

6

8

10

12

14

16

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

UUV SPEED [KTS]

PO

WE

R [

KW

]

Propulsion

Hotel

0

50

100

150

200

250

300

350

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

UUV SPEED [KTS]

RA

NG

E [

NM

]Range versus Speed

(38" dia. UUV with 500 W Hotel Load)

The Optimum AUV Power System

Performance to Complete Mission Affordable Cost

Speed

Weight

Stealth

Volume

Simple to Refuel

Exerciseability

EnvironmentallyBenign

Easy Turnaround

Direct Costs

Range

BatteriesFuel cells

Heat enginesThermoelectrics

Molecular Structure Definesthe Available Energy

H

Li

1

3

1.007

Hydrogen

Lithium

6.94

1

1

20.26814.025.0699

1s'

1s' 2s'

1615453.7

.53 Al26.9815

Aluminum

32793

933.252.70

[Ne] 3s2p1

O15.999

Oxygen

-290.1850.351.429

1s22s2p4

F18.998

Fluorine

-184.9553.481.696

1s22s2p5

Reactant Energy Density and Specific Energy

JP5/

LOX

Li/SF6

Al/H2O

LH2/LOX

Li/H2O

JP5/

atm

hp hr/ft^3

hp hr/100 lb

0

100

200

300

400

500

600

700

800

hp

hr

per

ft^

3 o

r 10

0 lb

m

Reactants

Fission U 235

JP5 in air (free)

Nuclear versus Chemical

lbmhrhp

10~ 7 ◊◊◊◊

lbmhrhp

10~◊◊◊◊

Grids21.50%

Top Lead4.70%

Container, lid, vent-

plugs, separators

10.30%

Electrolyte27.50%

Active Materials

36.00%

Batteries

Single Cell

Theoretical and Actual Capacity of Batteries

Handbook of Batteries & Fuel Cells, David Linden, ed., McGraw-Hill, Inc. 1984

Wat

t-h

ou

rs/k

ilog

ram

NOO Vehicle Batteries• Batteries mounted in 12”

aluminum cylinders.• Batteries arranged in pucks of

48 D-cells, 8 pucks in parallelper group, 4 groups per series (2groups per can).

• Room for 9 pucks per group, allpucks individually fused.

• With new batteries, open circuitvoltage ~288V; 230V underload.

• Intelligent interface boardmonitors temperature, groupcurrent, puck voltages, leak.

• Testing indicates batterycapacity is well aboverequirement for 300 nmi.

AAAARRRRLLLL

• Configurable – Can be ordered with different number of cells• Fairly quick delivery • Reasonable packaging effort required• Relatively cost effective

Texeco Ovonic GMO-090085 Ahr Nickel Metal Hydride Battery

Weight: 39.25 lbs for 11 cell battery

Volume: 453 cu. In for 11 cell battery

Estimate: 35.6 lbs for 10 cell battery 17.8 lbs for 5 cell battery

Nominal Capacity 1 85 AhrNominal Energy 1 1.2 KwhrSpecific Energy 1 67 Whr/kgEnergy Density 1 160 Whr/lPeak Specific Power 2 190 W/kgPeak Power Density 2 465 W/lCycle Life >500Discharge Rate 0 to 200A

1 – Based on a 30 A rate discharge to 1 volt/cell at 70∞F and a

90% manufacturing conformance level of initially achieving atleast 90% of specified value

2 – Based on calculation from 30 second constant currentdischarge of 300 amps at 70 ∞F

GMO-0900 Battery SpecificationsQuoted from manufacturer’s manual

AAAARRRRLLLL

-

+

+

+

+

-

-

--

+

+

+

+

-

-

--

+

+

+

+

-

-

--

+

+

+

+

-

-

--

+

+

+

+

-

-

--

+

+

+

+

-

-

--

+

+

+

+

-

-

--

+

+

+

+

-

-

--

+

+

+

+

-

-

--

+

+

+

+

-

-

-

LELFAS NiMH Battery Module

Configuration:

• 10 Rows of batteries• Each row:

• 2-Ten cell & 2-Five cell batteries• Total:

• 20 – Ten cell batteries (12V)• 20 – Five cell batteries (6V)

• Battery configurations allow for “finetuning” the total voltage and weight.

• 300 cells at nominal 1.2V = 360V• Total Battery Weight: 1070 lbs• Batteries will be operated and charged

in the “vent-up” orientation

AAAARRRRLLLL

• Total energy: ~ 35kW-hr• Usable energy will be less due to voltage and current

limitations

Battery Charging:

• Pre-run top off is needed, NiMH batteries are expected to lose up to 2%per day at 70∞∞∞∞F; 4% per day at 100∞∞∞∞F. (Back of a truck or deck of a

ship in summer)

• Low rate charging will be implemented through the umbilical. It willbe isolated before launch.

• Cyclic charging between runs accomplished with external powersupply. Control TBD.

• Shells will be vertically oriented for charging.

AAAARRRRLLLL

Fuel Cells

Schematic

System Testing

Load

e

H2O (uuuu),

N2, O2

ExcessHydrogen

H+

Hydrogen(fuel)

Air

Cathode

Proton ExchangeMembrane (PEM)

Anode

Stack

Fuel Storage

Reformeror

H2 Storage

Hydrogen Separator/Conditioner

FuelCell

StackPump

HeatExchanger

OxygenStorage/

Generator

OxygenConditioner

ExcessWater

and CO2

Fuel Cell System Schematic

48.2%29.7%173.84,653.23226,7772/1/1995Air Force934th Airlift

55.1%33.9%167.84,507.21826,85910/6/1995MarinesNaval HospitalMCB Camp

50.7%31.9%157.24,256.53227,0759/12/1995ArmyFort Eustis

63.0%31.5%171.64,872.37128,39311/17/1995ArmyUS MilitaryAcademy

77.3%31.4%142.64,117.73528,87510/29/1997ArmyWatervliet Arsenal

62.4%30.9%165.95,316.29132,05310/11/1995ArmyPicatinny Arsenal

61.2%31.2%165.26,379.23538,6081/27/1995ArmyU.S. Army SoldierSystems Center

76.1%30.2%150.76,387.53742,3751/23/1995NavyNaval StationNewport

MODEL B UNITS

AVAIL.ELEC.EFF.

AVGKW

MWHRSOUTPUT

OPER.HOURS

STARTDATE

SERVICESITE NAME

Site Performance Summary TableThrough January 31, 2002

98%27.0%92.337,2882,8601/18/2002Watervliet Arsenal/Manufacturing Facility

98%27.2%90.297,2072,8521/18/2002WatervlietArsenal/Research Facility

95%26.4%128.819,9653,9211/15/2002Watervliet Arsenal/Officer’s Quarters

Mar 6, 2002Geiger Field

Oct 2002*Patuxent River NAS

Oct 2002*Patuxent River NAS

Dec 2002*Barksdale AFB

Dec 2002*Ft. Jackson

Dec 2002*Ft. Bragg

Dec 2002*MCB Kaneohe Bay

Dec 2002*Brooks AFB

May 2002*Sierra Army Depot

Avail.Electri

EfficiencyInput Fuel

(MMBTU)

kWh

Output

Oper.

HoursFUEL CELLSTART-UP

SITE NAME

Site Performance Summary TableData through February, 2002

* Projected Fuel Cell Installation Date

O2(3000psiagas) H2O2(70%)

O2(6000psiagas) H2O2(90%)

NaClO3O2(liquid)

LiClO4

lbm O2/ft^3

lbm sub/ft^3

0

20

40

60

80

100

120

140

160

lbm

/ft^

3

Source

Oxygen Storage

H2(3000psia) FeTiHx

H2 LiquidCarbon

SWNT's ReformingAl(+H2O)

lbm H2/ft^3

lbm sub/ft^3

0.0

50.0

100.0

150.0

200.0

250.0

lbm

/ft^

3

Source

Hydrogen Storage

ckombustor

FuelTank

StirlingEngine

lternator

Balancer

Status:

3 kW Design, Prototype @ 2.2 kW

44% Efficiency Design, Prototype @35%

Prototype Engine Operated 100-hours

Heat Engine SystemsAAAARRRRLLLL

Stirling Engine

Schematic

Hot End

GasAlternator

Mover

Gas

DisplacerPiston

Gas

ColdEnd

REGENERATOR

AAAARRRRLLLL

Stirling HeaterTubes

PorousCombustorStructure

EnhancedSurfaceArea

Fuel FeedArteries

OxidantInjector

Trap / HeatShield

DifferentialPressureMembrane

Start /RestartModule

Fuel

Products

Flame

Wick Combustor8Li + SF6 6LiF + Li2 S

AAAARRRRLLLL

Compact Turbine/Alternators

1ST Generation

2ND Generation

3RD Generation

AAAARRRRLLLL

Isosurface is 12% liquid waterContours are diluent mass fraction

Max power - Max depth

5000.004375.003750.003125.002500.001875.001250.00625.00

0.00

Temperature

CombustorsC1 0 H1 9 + 14.75 O2 + 70 H2O 10 CO2 + 9.5 H2O + 70 H2OÆ

Fuel

Oxygen

Oxygen

Diluent

Diluent

MixedProducts

AAAARRRRLLLL

Thermo-photovoltaics/Thermoelectrics

(from Scientific American)

Thermal Radiator (ARL)

TPV Assembly (KAPL)

Converter Weights and Volumes

350 Hp Turbine _ Hp Stirling 1 Hp Fuel Cell

30 lbs.5 ft

355 lbs.25 ft

3

16 lbs.15 ft

3

Generating Electricity

3 Kw Alternator

3 Kw Alternator

.8 Kw Fuel Cell

3 lbs17 in

3

24lbs137 in

3 16 lbs248 in

3

.35 Kw Alternator

6 lbs38 in

3

Range vs Speed for SEAHORSE UUV(with various power systems)

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

0 2 4 6 8 10 12 14

Speed [knots]

Ran

ge

[nm

]

Wick/Stirling

Wick/Rankine

Lithium Battery (Primary)

Fuel Cell (Cryo)

JP5-3000 psi O2 (Rankine)

JP5 – H2O2 (Rankine)

Lithium Battery (Secondary)

Silver – Zinc Battery (Seconda

Summary

• No energy system is optimum for allapplications; most are for some.

• Performance varies by an order-of-magnitude among the candidates.

• Cost and performance tend to varyinversely.

• Expect about a twofold improvement inemerging technologies in the next decade.