LIQUEFIED NATURAL GAS FUEL TANK
MAE 435 – Final Presentation
Advisor: Dr. Zhang
Liebherr representative: James Whitfield
-Albert Ochagavia
-Pithan Rojanavongse
-Josh Harris
-John Alexander
LNG Background
What is LNG?Liquefied Natural Gas-162° C1/600 volume of Natural Gas
Why use it?CostAvailabilityEfficiencyEnvironment
Project Statement
To design and analyze a Liquid Natural Gas (LNG) fuel tank for Liebherr’s current T 264 mining truck that conforms to all Pressure Vessel and LNG regulations and fits in the space available on the mining vehicle.
Project Goals
Design LNG Tank to fit Liebherr’s current T 264 Mining Truck
Maximize Volume for 8-12 hour operational time (35% work load)
Strictly follow pressure vessel and LNG standard regulations
Perform a Finite Elemental Analysis of the tank using SolidWorks
Tank Design Parameters
Space Available
AssumptionsLoad factor of 35%LNG engine efficiency equivalent to DieselASTM Boiler and Pressure Vessel CodeSame tank design will be used for both tanks
Inner Tank
A240 Type 304 Stainless Steel Total volume: 1800 L Thickness: 1.75 inches 2 parts (Shielded Metal Arc Welding Method)
Ullage TankVolume: 180 LIncreases hold timePump less fuel methodFull tank gauge
RivetsDiameter: 2.5 inchesLength: 3 inchesVertical and
horizontal support
Insulation Layer
Multi Layer Insulator (MLI) 1 inch thickness Low thermal conductivity
K= 0.0001 W/m-k High thermal resistance
R=1440 m^2K/W
Outer Shell
A240 Type 304 Stainless Steel Made of 2 parts
Shielded Metal Arc Welding Method Allows vacuum Placement for rivets at the bottom
Gauges
Three Companies: Omega, Ashcroft, and WIKA Two Gauges:
Fuel Standard Size: ~ 2”
Pressure Maximum tank pressure: 420 psi Average Size: 1 – 2 ½”
Properties: High pressure High shock resistant Cryogenic temperatures (304 SS)
Fueling Methods Standard Diameter: 1 ½ “
Time efficient
Prevention of temperature and pressure changes
Function at cryogenic temperatures and atmospheric pressure
50 Gallons Per Minute
Material: Stainless Steel
The majority of companies are developing similar fueling methods
Quick disconnect and fueling
Parker, CryoMac, Carter, etc.
50 gallons per minute
Stainless steel
Three Major Components Vent
Removing warmer gas Sub-cooling LNG residual Decrease in pressure LNG facilities may have a vent connection
Liquid For defueling tank (emergency situations)
Relief Valves Reduces pressure Safety feature
Rules & Regulations NFPA 57 – Liquefied Natural Gas Vehicular
Fuel Systems Code Design, installation, operation, and maintenance of
LNG engine fuel systems on vehicles of all types SAE J2343 – Recommended Practice for
LNG Medium and Heavy-Duty Powered Vehicles
Guidance for construction, operation, and maintenance of LNG heavy-duty vehicles for public transit and commercial applications
Safety Features
Ullage Tank Pressure Relief Valves
350 psi400 psi
Emergency Shutoff Valves Defueling connection
Finite Element Analysis
Weight Analysis (4000 lbs)Yielding stress 207 MPa (304 SS)Max stress from FEA 22 MPa
Finite Elemant Analysis
Pressure (420 psi)Yielding stress 207 MPa (304 SS)Max stress from FEA 190 MPa
Goals (2)
Design a single LNG Tank to fit Liebherr’s current T 264 Mining Truck
Designed a tank that fits and has an approximate volume of 1800 L Maximize Volume for 8-12 hour operational time (35% work load)
Total of 3500 L = 11-12 hour of operation time Strictly follow pressure vessel and LNG standard regulations
NFPA 57 SAE J2343 Perform a Finite Elemental Analysis of the tank using SolidWorks
Max stress < yielding stress for 304 stainless steel (207 Mpa)