r407c air conditioning system simulation with numengo|fl - simulationx

© numenGo | www.numengo.com 1/19

Air Conditioning systems simulation with numenGo|FL

Example of a R407C AC loop

http://www.numengo.com/


Air Conditioning loop specifics

● Media● Refrigerant

● Two-phase description● R407C : mixture !

● Moist Air● Influence of relative humidity● Condensation

● Two phase flows● Two-phase pressure drops● Two-phase heat convection

● Boiling● Condensation

● Heat Exchanger● Extended Surface● 2D external flow

1. condenser2. expansion valve3. evaporator4. compressor



numenGo

● Thermal Fluids modeling and simulation specialists● Our Vision

● Capitalize modeling know-how in evolutive, generic, platform independant libraries

numenGo | FFCnumenGo|FL

numenGo | MPS

SIMULATION PLATFORMC

r yo ge n ic s

Pr op ul si on

etc ..

Business Oriented Library

APPLICATIVESOLUTIONS

THEIR expertise

OUR expertise

YOUR expertise



numenGo

● Thermal Fluids modeling and simulation specialists● Our Vision

● Capitalize modeling know-how in evolutive, generic, platform independant libraries


numenGo | MPS

SIMULATION PLATFORM

HV

AC

Moist-Air Add-on

APPLICATIVESOLUTIONS

Heat Exchanger Add-on



Software Components

● numenGo|FLContains high level components


numenGo | MPS

SIMULATION PLATFORM

Moist-Air Add-on Heat Exchanger Add-on



Software Components

● numenGo|FLpolymorphic components

Thermodynamic sources

flow sources

Heat exchanges



Software Components

● numenGo|FLpolymorphic components

● Pipes● Distributed models

● Dynamic discretization

● Flexible geometry● Optional Inertial effects● Convective heat exchange



Software Components

● numenGo|MPS

● A Media Property Server to compute fluid or solids thermodynamic properties, optimized for system simulation

● Compute thermodynamic properties for all state of matter:● Liquid, gas, two-phase or solid● Pure compound or mixture

● From simple description (ie perfect gas) to most precise state of the art descriptions (ie fundamental equation of state of Helmholtz, ECS, etc...

New Feature hightlight : 2-phase mixtures


numenGo | MPS

SIMULATION PLATFORM




Software Components

● numenGo|MPS : 2-phase mixtures

● Equation of state : GERG2004/2008● Transport properties : Extended Corresponding States

Optimized for system simulation



Software Components

● numenGo|FFC

provides all base objects to solve mass and heat transfer

● Mass transfer models● Flow equations

● incompressible, real fluid compressible, perfect gas compressible

● Flow resistance models● Friction factor models (Colebrook, Churchill,...)● Flow resistance models (2-K method, Cq, Crane...)● Two-phase flow

● Two-phase correlations (Friedel, Bankoff...)● Slip ratios (homogeneous, Chisholm, Zivi...)● Bulk properties (Dukler, Cicchitti, McAdams...)

● Flow component models (tee junction, pumps, turbines, ejectors...)


numenGo | MPS

SIMULATION PLATFORM




Software Components

● numenGo|FFC

provides all base objects to solve mass and heat transfer

● Heat transfer models● Conduction● Forced and free convection

● NTU● Two-phase forced convection

● Boiling (Chen, VDI...)● Condensation (Shah, Cavallini & Zecchin...)

● Radiation



Software Components

● Moist-Air add-on● Single condensate / vapour mixture equilibrium● Sources, sensors with humidity variable

● Heat Exchanger add-on● 2-D air flux components to describe air flow profiles● Extended surface heat exchanger components


numenGo | MPS

SIMULATION PLATFORM




AC loop model



AC loop model

● Condenser modeling

pass 1 : 9 plates

pass 2 : 6 plates

pass 3 : 4 plates

plate/fin convective exchange

plate/fin solid thermal capacity

internal convective exchange

internal flow



● Fin/plate assembly● Geometrical description● Dynamic discretization

● Flow● Wall● Air Flow



AC loop model

● Evaporator modeling

3 passes of 6 plates

plate/fin convective exchange

plate/fin solid thermal capacity

internal convective exchange

internal flow



Air Flow results

● Visualization of air profiles● Temperature, velocity, relative humidity over time



AC loop - Possible studies

● Refrigerant loop sizing and optimization

● Cycle performance

● Stability analysis

● Control strategies & normalized cycles

● Heat Exchanger stacking

● Thermal synthesis



Conclusion

● numenGo|FL● Advanced generic library for thermal fluid MBSE

● 2-phase mixtures NEW● State of the art descriptions● Optimized algorithms for system simulation● Fixed and variable composition● Extensive and scalable database

● Refrigerants, NLG, etc...

● Moist-Air and Heat Exchanger add-ons NEW● Water condensation● 2D external flows – heat exchanger stacking● Extends numenGo|FL for ECS and HVAC applications
