Prsentation PowerPoint

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JOURNEES FRANCOPHONES TRNSYS 2003 Temperature,
humidity and pollutants in the passenger
compartment of a car (with and without
recycling) Alain Cordier (A. C. E. T.)
cordial_at_club-internet.fr Jean-Marc Puel (Réalix
technologies) puel_at_realix.fr
METHOD First step Use of a CFD software
- partionnig of the interior of the car in
18 cells - Determination of the air flowrate at
the inlets of each cell - Determination of the
convection coefficients on the walls Second
step Modelling (FORTRAN) for TRNSYS -
enthalpy, humidity and pollutants transfers from
cell to cell - enthalpy, humidity and
pollutants coming from outside - enthalpy,
humidity and pollutants internal gains -
enthalpy, humidity and pollutants balance for
each cell - The heating-air conditionning
device, with its fan and a variable volume
compressor Third step Use of TRNSYS with
IISiBat
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USE OF C. F. D. PARTITIONNING IN CELLS

• - SIMPLIFICATION of the description file of the
  car
• MODELLING with FLOTHERM (CFD) of a large number
  of ZONES
• - MERGING of these zones in 18 CELLS
• - Determination of the air flowrates penetrating
  each cell
• - Determination of the convection coefficients
  on the inner surfaces

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USE OF TRNSYS CELLS
Computations
EXTERNAL SOURCES

• - Orientation, slope of windows and walls
• - Thermal and optical properties of materials
• Sun azimut and zenith angle
• Outside temperature
• Convection coefficients

• Surface temperatures of the opaque walls
• Inner surface temperature of the windows
• Solar energy collected by all the windows
• - Heat transfers

PARAMETER
INTERNAL SOURCES
- Occupants area of the body heads - Solar
energy through the windows
- Production of heat, humidity and pollutants -
Solar energy for each cell
PARAMETER
INPUT
DE CELLULE A CELLULE et venant du système de
CHAUFFAGE-CLIMATISATION

• - Volumic flowrates
• - Air temperature
• Humidity
• - Concentrations of pollutants

PARAMETER
- Imported and exported enthalpy - Imported and
exported amount of water - Imported and exported
amount of pollutants
INPUT
- Temperature - Relative humidity - Condensation
of water on the windows - Concentrations of
pollutants
OUTPUTS of each cell
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DEFINITION DE LA CELLULE
PARAMETERS
INPUTS
OUPUTS
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USE OF IISiBat 18 cells 1 macro


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USE OF TRNSYS HEATING AND AIR CONDITIONNING
DEVICE
AIR INLETS
- Full new air 100 from outside - Recycling
90 from a cell 10 from outside - Inputs
temperature, relative humidity, concentrations by
each inlet - Calculation of mean values of
temperature, absolute humidity and pollutant
concentrations
THE FAN
- Air enthalpy raised by the power of the fan
AIR CONDITIONNING

• Temperature, absolute humidity at the outlet of
  the cold exchanger with and without
  condensation
• on the evaporator
• - Choice of the outlet temperature
• - Automatic adaptation of the volume of the
  compressor

HEATING
- Outlet temperature limited by the power of the
hot exchanger
OUTPUT
- Temperature, absolute and relative humidities,
concentrations of pollutants
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LA CENTRALE CHAUFFAGE-CLIMATISATION
INPUTS
PARAMETERS
OUPUTS
INPUTS
OUPUTS
DISTRIBUTION DES ENTREES
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Air conditionning
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LA FEUILLE DE TRAVAIL IISiBat

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Comparison experiment-simulation Air
conditionning, recycling, sun
experiment
simulation

(no scale for temperature and humidity
confidentiality)
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Comparison experiment-simulation Air
conditionning, without recycling, sun
experiment
simulation

(no scale for temperature and humidity
confidentiality)
Remark no experimental data available for
pollutants