2013 Aero Conference AeroFuelSystems

LMS Imagine.Lab AMESim

for Aircraft Fuel System Analysis

LMS, A Siemens Business

Bob Ransijn – Sr. Application Engineer

3 - Copyright LMS International - 2013

Some specific Fuel System requirements

Certification Dossier requires to go over a huge amount of configurations

Inerting capabilities are critical

Oxygen release in altitude

Temperature in tanks has to be closely controlled

Jettison

The Fuel system is critical for every mission

Management of fuel during the flight to ensure correct flow rate to the engine

Operations are impacted by refuelling

Vaporization and venting are to be analysed during the whole mission

Dynamic of the Aircraft is impacted by the fuel system

Acceleration is acting on the fluid which acts on the aircraft structure

Fuel can be used for stability increase (in fighters)

Fuel System have more than one use during the mission

Cooling of hydraulic circuit

Stability of the aircraft


A complex system involving multi domain

Fuel itself is a liquid

Thermal Hydraulic system

Pressurization, Venting and inerting are ensured

with gas

Pneumatic system

Gas concentrations are considered

Being used as heat sink

Thermal system

Sensitive to ambient condition

Aircraft mission (altitude, speed)

Aircraft attitude

Impacts Aircraft dynamic


Example of Fuel Metering System

Fuel Metering System

Ptank Boost Pump

Main Pump

Metering Valve

MPSOV FDV

PRV

Servo Reg

Servo Valve

Solenoid

EBV

Pd

P1

Pprv

P2

Pr

Pm

Ppes

Pfm

Ppri

Psec

Pfdv Pmpsov

Ttank

FOHE

Tin Tout

Tfuel

Tmix

Characteristics of Components:

Boost and Main pumps

Pressure Relief Valve

Servo Regulator

Servovalve

Metering valve

MPSOV (Shut of Valve)

Solenoid

FDV (Fuel Divider Valve)


AMESim models – Fuel Metering System

Functional modeling using standard AMESim component


P1

Pd

Pprv

Level 0 – Steady state model

Level 1 – First order dynamic

Level 2 – Second order dynamic


Detailed modeling – geometrical parameters

High dynamics


PRV

P1

Pprv

Pd


P1

Pd

Pprv

Level 3 – High frequency analysis


Create your own AMESim multi-level library…


PRV

P1

Pprv

Pd


P1

Pd

Pprv

P1

Pd

Pprv


Geometrical Valve Modeling

Hydraulic part: flow passages, volumes

Using AMESim hydraulic and hydraulic component design library

Mechanical part: mass, spring, friction

Using AMESim mechanical library

Extract pressure surfaces and exact flow

passage openings from 3D geometry

Spool with annular orifices


Metering Valve + Nozzle


Complete fuel injector model

Full system integration allows to see the

interaction between the different nozzles,

valves and manifold


FCU : Fuel Control Unit, example

LMS Imagine.Lab AMESim and its libraries (HYD,HCD,THH,THCD…) can be used to

model FCU/FMU systems at geometrical / detailed level. The typical use of AMESim in

this field covers :

Preliminary design phase

Design of components

Specifications of related

subsystems:

Analysis of metering

robustness

Analysis of pressure

pulsations to ensure a

constant flow to the

combustors

Analysis of the system on a

wide range of operating

conditions

Failure cases and back-up

modes


13 Confidential Material – LMS North America

AMESim models – Heat Exchangers

13 copyright LMS International - 2010

The Complete sub-system

Fuel/Oil Cooler Air/Oil Cooler

Half Heat Exchanger Heat Transfer Calculation

Only 2 different components


14 Confidential Material – LMS North America

AMESim models – Heat Exchangers

Standard AMESim component

No dynamics

14 copyright LMS International - 2010

Heat flow Exchange (effectiveness)

NOTE: for each component, the online help does describe all the used physical

assumptions and equations.


Fuel Metering + Engine + +Gearbox + Lubrication

Lubrication circuit connected to fuel circuit with fuel/oil heat exchanger

Custom component for dynamic combustion process

Full dynamic valve and line response for high transient analysis


Aircraft Fuel Systems library (N)

NEED

Analyze fuel systems taking thermal balance in

tanks and transient flow from tank to tank into

account?

NEW CAPABILITIES

New Aircraft Fuel Systems library & new

Aircraft Fuel Systems solution 3D Tank model with thermal exchanges

Import tank information from CAD files

Apply 3D orientation and acceleration

Gauge models

Orifice model between tanks

Library manual and submodels

Tutorials and demonstrators

BENEFITS

Assess the dynamic behavior and thermal

integration of fuel within the global aircraft

environment (thermals, gravitation…)


Fuel System – Tank Modelling – Topics

Main Topics

Tank Shape;

Yaw, Pitch and Roll angles;

Fuel flow rate;

Pressurization with inert gas;

Tank cascading;

[O2]/[N2] valuation;

Gravity and external acceleration;


Fuel system – Tank Modelling – Thermodynamic model

Dynamic model in AMESet:

Tank Shape;


Fuel flow rate;


Tank cascading;




Fuel system – Tank Modelling – Tank cascading

Dynamic model :

Tank Shape;


Fuel flow rate;


Tank cascading;


Vaporization effect;


Sloshing effect.


Fuel system – Tank Modelling – System verification

System verification in AMESim:

Tank Shape;


Fuel flow rate;


Tank cascading;



Courtesy of Embraer


Fuel system – Tank Modelling – Gas Mixture

System verification:

Tank Shape;


Fuel flow rate;


Tank cascading;



The system allows the user to:

Evaluate the evolution of the fractions of gas in the bays, depending on the source position and flow rate;

Evaluate the filling delay in order to compute the time needed in case of fire

Size the vent connection in order to avoid supersonic flow through the orifice;

Compute thermal aspects depending on the gas flow rate.


Fuel system – Tank Modelling – Gas Mixture

Some results:

Tank Shape;


Fuel flow rate;


Tank cascading;




LMS Imagine.Lab AMESim

The integrated platform for multi-domain system simulation

Environmental Control Systems

Bleed Air

Anti-Icing

Ventilation Circuit

Oxygen and Life System

Power & Distribution Networks

Hydraulic Systems

Pneumatic Systems

Electrical Systems

Electrical Wire Harness

Landing Gear

Actuation Systems

Braking Systems

Steering Systems

Shock Absorber

Engine Equipment

Fuel Metering Systems

Lubrication

Heat Exchangers

Thrust Reversers

Equipment Box

Flight Controls

Primary and Secondary Flight Controls (EHA, EMA)

High-lift Devices, Spoilers, Air Brakes

Fuel System

Fuel management

Inerting System

Filling

Thermal management

Documents

2013 Aero Conference AeroFuelSystems