EBSILON®Professional Online Documentation
EBSILON Professional Components / Components - General and Categories / Pumps and Compressors / Component 159: Map based Compressor
In This Topic
    Component 159: Map based Compressor
    In This Topic

    Component 159: Map based Compressor

    Specifications

    Line connections

    1

    Medium inlet

    2

    Medium outlet

    3

    Logical inlet

    4

    Shaft inlet

    5

    Shaft outlet

    6

    Control inlet (currently unused)

     

    General       User Input Values       Map tables       Physics Used       Displays       Example

     

     

    General

    Component 159 represents a map-based compressor which models its flow rate vs. pressure rise vs. rotational speed behaviour. The component tries to use the maps from the manufacturer directly without much manual conversion by the user. Maps can be imported via an importer tool, which allows to manually convert a compressor map image to a compressor map table.

    The compressor map is represented by (X,Y,Z,EFF) data points with various options for X,Y,Z,EFF. The calculation modes allow to calculate any of X,Y,Z from the two others.

    In order to derive the correct dimensionless reduced flow and reduced speed, if used in the settings, it is necessary to set the correct reference properties MW_REF, T_REF, P_REF, Z_REF, K_REF.

    If the map is given in terms of mach numbers, it is necessary to set the dimensions DIN and DIMP, in order to be able to calculate actual mach numbers

    If the efficiency and pressure rise are given as total to static, it is necessary to set the outlet diameter DOUT, in order to convert between total and static properties.

    If performance factors are activated, the following relationships are used:

    EFF = EFF_from_map_lookup * PFEFF (FCALC=1,2,3)
    X = X_from_map_lookup * PFX (FCALC=2)
    Z = Z_from_map_lookup * PFZ (FCALC=1)
    X_used_in_map = X / PFX (FCALC=1,3)
    Z_used_in_map = Z / PFZ (FCALC=2,3)

    User Input Values 

    FCALC

    Flag for the calculation mode:

    =0: Bypass (out=in)
    =1: calculate Z(X,Y)
    =2: calculate X(Y,Z)
    =3: calculate Y(X,Z)

    MW_REF

    Inlet reference molecular weight

    T_REF

    Reference inlet temperature

    P_REF

    Reference inlet pressure

    Z_REF

    Reference inlet compressibility factor Zref = Pref*Vref/(R*Tref)

    K_REF

    Reference inlet isentropic exponent (k=cp/cv)

    F_USE_Z_REF

    Flag for the usage of Z_REF:

    =0: NO (no usage of Z_REF and Z in the calculation of corrected flow and corrected speed)
    =1: YES (use Z_REF and Z when calculating corrected flow and corrected speed)

    DIN

    Inlet diameter

    DOUT

    Outlet diameter

    DIMP

    Impeller diameter

    N_REF

    Reference corrected rotational speed
    FN_REF

    Flag for shaft speed in IGV mode

    =0: Emit N_REF as shaft speed
    =1: shaft speed set externally

    FX

    Flag for X definition:

    =0: X is corrected flow
    =1: X is axial mach number
    =2: X is volume flow

    FY

    Flag for Y definition:

    =0: Y is corrected speed
    =1: Y is rotational mach number
    =2: Y is relative corrected speed
    =3: Y is IGV angle on logic port 3 H

    FZ

    Flag for Z definition:

    =0: Z is pressure ratio
    =1: Z is isentropic head
    =2: Z is outlet pressure. The pressure ratio used will be calculated as PR=Z/P_REF

    FEFF

    Flag for efficiency Input (map MXCMAP, column 4):

    =0: set efficiency
    =1: set power consumption

    FPREFF

    Flag for PR and EFF definition:

    =0: PR and EFF are total-to-static isentropic
    =1: PR and EFF are total-to-total isentropic
    =2: PR and EFF are total-to-total polytropic

    EFFM

    Mechanical efficiency (fraction)

    LOSSM

    Mechanical loss (constant)

    FPFEFF

    Flag for performance factor efficiency:

    =0: None
    =1: use value PFEFF
    =2: use expression EPFEFF
    =3: use map MXPFEFF

    PFEFF

    Performance factor efficiency

    EPFEFF

    Expression for performance factor efficiency

    FPFX

    Flag for performance factor X (mutually exclusive to FPFZ):

    =0: None
    =1: use value PFX
    =2: use expression EPFX
    =3: use map MXPFX

    PFX

    Performance factor X

    EPFX

    Expression for performance factor X

    FPFZ

    Flag for performance factor Z (mutually exclusive to FPFX):

    =0: None
    =1: use value PFZ
    =2: use expression EPFZ
    =3: use map MXPFZ

    PFZ

    Performance factor Z

    EPFZ

    Expression for performance factor Z

    The parameters marked in blue are reference quantities for the off-design mode. These are calculated and entered here during the design calculation of EBSILON®Professional.

    Generally, all inputs that are visible are required. But, often default values are provided.

    For more information on colour of the input fields and their descriptions see Edit Component\Specification values

    For more information on design vs. off-design and nominal values see General\Accept Nominal values

    Map Tables

    MXCMAP

    col1=Y

    col2=X

    col3=Z

    col4=EFF or PWR

    Compressor map core table

    MXSURGE

    col1=X

    col2=Z

    Surge line limit

    MXEFFISO

    col1=ID

    col2=X

    col3=Z

    col4=EFF

    Iso efficiency lines. Not used in calculations, only within the importer tool

    MXPFEFF

    col1=Y

    col2=X

    col3=PFEFF

    performance factor correction efficiency

    MXPFX

    col1=Y

    col2=Z

    col3=PFX

    performance factor correction X

    MXPFZ

    col1=Y

    col2=X

    col3=PFZ

    performance factor correction Z

     

    Result values

     

    Q

    Shaft power

    RFLOW

     Corrected flow

    RSPEED

    		 Corrected rotary speed

    RELRSPEED

    Relative corrected rotational speed

    FLOW

    Flow
    SPEED              

     

    Shaft rotary speed

     

    PR_TT

    Pressure ratio total-total

    PR_TS

    		 Pressure total-static 

    P1_T

    Inlet pressure total

    P1_S

    Inlet pressure static

    P2_T

    Discharge pressure total

    P2_S

    Discharge pressure static

    MCH_AX

    Mach-number axial

    MCH_RAD

    Mach-number radial

    RIGV                 

    Inlet Guide Vane Angle (IGV)

    EFFI_TT

    Efficiency isentropic total-total

    EFFI_TT

    Efficiency isentropic total-static

    EFFP_TS   

    Efficiency polytropic total-total

    EFFP_TT

    Used value of the adjustment polynomial
    This value is only calculated if the fitting polynomial is also used, otherwise it is 1.

    HDISEN_TT

    		                

    Isentropic head total-total

    HDISEN_TS

    Isentropic head total-static

    VM1

    Inlet volume flow

    RPFEFF

    Performance factor efficiency

    VM1

    Inlet volume flow

    RPFX

    Performance factor  X

    RPFZ

    Performance factor  Z

     

    Physics Used

    FCALC = 0

    Bypassmode.
    Set port2 = port 1
    Set shaft power = 0

    FCALC = 1

    Calculate Z(X,Y)
    Determine X from input flow
    Determine Y from shaft speed
    Lookup Z and EFF from (X,Y) in MXCMAP
    Determine outlet pressure from Z
    Determine shaft power from EFF

    FCALC = 2

    Calculate X(Y,Z)
    Determine Z from outlet pressure
    Determine Y from shaft speed
    Lookup X and EFF from (Y,Z) in MXCMAP
    Determine inlet flow rate from X
    Determine shaft power from EFF

    FCALC = 3

    Calculate Y(X,Z)
    Determine X from input flow
    Determine Z from outlet pressure
    Lookup Y and EFF from (X,Z) in MXCMAP
    Determine shaft speed from Y
    Determine shaft power from EFF

    Equations

    M2 - M1 = 0

    M5 - M4 = 0

    H2 - H1 = dH

    H5 - H4 = -M1 * dH * EFFM

    P2 - pressure_ratio * P1 = 0 (FCALC = 1)

    M1 = inlet_flow (FCALC = 2)

    M4 = RPM (FCALC = 3)

    Component Displays

    Display Option 1: Compressor

    Display Option 2: Axial Compressor

    Display Option 3: Radial Compressor

    Example

    Click here >> Component 159 Demo << to load an example.

     

     

    Copyright Iqony Solutions GmbH 2024 Built at 05.09.2024

    Impressum Disclaimer