dx_air_cooling_coil_cv.F90

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!SFX_LIC Copyright 1994-2014 CNRS, Meteo-France and Universite Paul Sabatier
!SFX_LIC This is part of the SURFEX software governed by the CeCILL-C licence
!SFX_LIC version 1. See LICENSE, CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt  
!SFX_LIC for details. version 1.
SUBROUTINE dx_air_cooling_coil_cv(PT_CANYON, PQ_CANYON, PPS, PRHOA,    &
                             pt_in, pq_in, pcop_rat, pcap_sys_rat,     &
                             pt_adp, pf_water_cond,                    &
                             pm_sys, ph_bld_cool, ph_waste, ple_waste, &
                             pcop, pcap_sys,  pt_out, pq_out,          &
                             pdx_power,  pt_bld_cool      )
!
USE mode_thermos
USE mode_psychro
!
USE modd_csts, ONLY : xcpd
!
USE yomhook   ,ONLY : lhook,   dr_hook
USE parkind1  ,ONLY : jprb
!
! Extracted from EP_Engineer_ref p. 518
!
REAL, INTENT(IN) :: pt_canyon        ! Canyon air temperature [K]
REAL, INTENT(IN) :: pq_canyon        ! Canyon air humidity ratio [kg kg-1]
REAL, INTENT(IN) :: pps              ! Canyon air pressure [Pa]
REAL, INTENT(IN) :: prhoa            ! Canyon air density [kg m-3]
REAL, INTENT(IN) :: pt_in            ! Actual inlet air temperature [K]
REAL, INTENT(IN) :: pq_in            ! Actual inlet air humidity ratio [kg kg-1]
REAL, INTENT(IN) :: pcop_rat         ! Rated COP
REAL, INTENT(IN) :: pcap_sys_rat     ! Rated capacity [W]
REAL, INTENT(IN) :: pt_adp           ! Apparatus dewpoint [K]
REAL, INTENT(IN) :: pf_water_cond    ! fraction of evaporation of the condenser
REAL, INTENT(INOUT) :: pm_sys        ! HVAC air mass flow rate [kg s-1]
REAL, INTENT(INOUT) :: ph_bld_cool   ! Sensible cooling load
REAL, INTENT(OUT) :: ph_waste        ! Sensible heat rejected by the condenser [W]
REAL, INTENT(OUT) :: ple_waste       ! Latent heat rejected by the condenser [W]
REAL, INTENT(OUT) :: pcop            ! Actual COP
REAL, INTENT(OUT) :: pcap_sys        ! Actual capacity [W]
REAL, INTENT(OUT) :: pt_out          ! Actual outlet temperature [K]
REAL, INTENT(OUT) :: pq_out          ! Actual outlet humidity ratio [kg kg-1]
REAL, INTENT(OUT) :: pdx_power       ! Electrical power consumed by the DX unit [W]
REAL, INTENT(OUT) :: pt_bld_cool     ! Total energy supplied by the DX unit [W]
!
REAL :: ztwb_canyon   ! Canyon air wet-bulb temperature [ K]
REAL :: zcaptemp      ! Total cooling capacity modifier curve function of temperature
REAL :: ztw_in        ! Wet-bulb temperature of the air entering the coil [ K]
REAL :: zt_cond       ! Dry-bulb or wet-bulb air temperature entering the condenser [K]
REAL :: zeirtemp      ! Energy input ratio modifier curve function of temperature
REAL :: zplr          ! Part load ratio
REAL :: zpartloadf    ! Part load fraction correlation
REAL :: zshr          ! Actual coil sensible heat rate
REAL :: zh_adp        ! Enthalpy of air at ADP conditions [J/kg]
REAL :: zh_out        ! Enthalpy of air leaving the cooling coil [J/kg]
REAL :: zh_in         ! Enthalpy of air entering the cooling coil [J/kg]
! Performance curves coefficients
REAL :: za1
REAL :: zb1
REAL :: zc1
REAL :: zd1
REAL :: ze1
REAL :: zf1
! Total cooling capacity modifier curve function of flow fraction (desactivated)
!REAL :: ZCAPFLOW      
!REAL :: ZA2
!REAL :: ZB2
!REAL :: ZC2
REAL :: za3
REAL :: zb3
REAL :: zc3
REAL :: zd3
REAL :: ze3
REAL :: zf3
! Energy input ratio modifier curve function of flow fraction (desactivated)
!REAL :: ZEIRFLOW      
!REAL :: ZA4
!REAL :: ZB4
!REAL :: ZC4
REAL :: za5
REAL :: zb5
REAL :: zc5
REAL(KIND=JPRB) :: zhook_handle
!
IF (lhook) CALL dr_hook('DX_AIR_COOLING_COIL_CV',0,zhook_handle)
!
!*      A.     Definitions
!              -----------
!
!
!*      B.     Performance curves
!              ------------------
! Total cooling capacity modifier curve function of temperature
! Obtained from default vaules of EnergyPlus SingleSpeedDX
! DOE-2.1E, COOL-CAP-FT for PTAC w/ SI temps
!  FurnaceDX DX Coil Cap-FT, Minimum Value of x, 12.77778;  
!                            Maximum Value of x, 23.88889;
!                            Minimum Value of y, 23.88889;
!                            Maximum Value of y, 46.11111
za1 =  0.942587793   !- Coefficient1 Constant
zb1 =  0.009543347   !- Coefficient2 x
zc1 =  0.00068377    !- Coefficient3 x**2
zd1 =  -0.011042676  !- Coefficient4 y
ze1 =  0.000005249   !- Coefficient5 y**2
zf1 =  -0.00000972   !- Coefficient6 x*y
! Total cooling capacity modifier curve function of flow fraction
! DOE-2.1E, RATED-CCAP-FFLOW for PTAC
!  FurnaceDX DX Coil Cap-FF, Minimum Value of x, 0.5;  
!                            Maximum Value of x, 1.5;
!ZA2 =  0.8           !- Coefficient1 Constant
!ZB2 =  0.2           !- Coefficient2 x
!ZC2 =  0             !- Coefficient3 x**2
! Energy input ratio modifier curve function of temperature
! DOE-2.1E, COOL-EIR-FT for PTAC w/ SI temps
!  FurnaceDX DX Coil EIR-FT,  Minimum Value of x, 12.77778;  
!                            Maximum Value of x, 23.88889;
!                            Minimum Value of y, 23.88889;
!                            Maximum Value of y, 46.11111
za3 = 0.342414409    !- Coefficient1 Constant
zb3 = 0.034885008    !- Coefficient2 x
zc3 = -0.0006237     !- Coefficient3 x**2
zd3 = 0.004977216    !- Coefficient4 y
ze3 = 0.000437951    !- Coefficient5 y**2
zf3 = -0.000728028   !- Coefficient6 x*y
! Energy input ratio modifier curve function of flow fraction
! DOE-2.1E, RATED-CEIR-FFLOW for PTAC
!  FurnaceDX DX Coil EIR-FF, Minimum Value of x, 0.5;  
!                            Maximum Value of x, 1.5;
!ZA4 = 1.1552         !- Coefficient1 Constant
!ZB4 = -0.1808        !- Coefficient2 x
!ZC4 = 0.0256         !- Coefficient3 x**2
! Part load fraction correlation
! PLF = l.- Cd(1.-PLR) where Cd = 0.15
!  FurnaceDX DX Coil PLF, Minimum Value of x, 0.0;  
!                         Maximum Value of x, 1.0;
za5 = 0.85           !- Coefficient1 Constant
zb5 = 0.15           !- Coefficient2 x
zc5 = 0              !- Coefficient3 x**2
!
!
!*      C.     Total cooling capacity 
!              ----------------------
! 
IF (pm_sys/prhoa/pcap_sys_rat < 0.00004027) THEN
     pm_sys = 0.00004027*pcap_sys_rat*prhoa
!     PRINT*,'ERROR: HVAC supply air flow rate must be greater than 0.00004027m3/s/W'
ELSE IF (pm_sys/prhoa/pcap_sys_rat > 0.00006041) THEN
     pm_sys = 0.00006041*pcap_sys_rat*prhoa
!     PRINT*,'ERROR: HVAC supply air flow rate must be lower than 0.00006041m3/s/W'
END IF
!
! Wet-bulb temperature entering the cooling coil
ztw_in      = twb_from_tpq(pt_in, pps, pq_in)
!
! Dry-bulb temperature of the air entering an air-cooled condenser 
! or wet-bulb temp entering a water-cooled condenser
ztwb_canyon = twb_from_tpq(pt_canyon, pps, pq_canyon)
zt_cond     = ztwb_canyon + (pt_canyon - ztwb_canyon)*(1. - pf_water_cond)
!
! Total cooling capacity modifier curve function of temperature
zcaptemp = za1 + (ztw_in -273.15) * (zb1 + zc1*(ztw_in -273.15)) &
               + (zt_cond-273.15) * (zd1 + ze1*(zt_cond-273.15)) &
               + (ztw_in -273.15) * (zt_cond-273.15) * zf1
!
! Total cooling capacity
pcap_sys = pcap_sys_rat * zcaptemp
!
!*      D. Coil outlet conditions
!          ----------------------
!
! Inlet air enthalpy
zh_in  = enth_fn_t_q(pt_in,pq_in)
! Apparatus dewpoint enthalpy
zh_adp = enth_fn_t_q(pt_adp,qsat(pt_adp,pps))
!
! Cooling coil sensible heat rate
IF (zh_in - zh_adp < 10.) THEN
  !
  zshr = 1.
  !
  pt_out = pt_adp
  pq_out = pq_in
  zh_out = enth_fn_t_q(pt_out,pq_out)
  pt_bld_cool = 0.0
  !
ELSE
  !
  zshr  = min(xcpd*(pt_in - pt_adp)/(zh_in - zh_adp), 1.) !
  !
  ! Thermal load limited by the system capacity
  IF ( ph_bld_cool > pcap_sys * zshr ) ph_bld_cool = pcap_sys * zshr
  !
  ! Outlet air temperature
  pt_out = pt_in - ph_bld_cool / pm_sys / xcpd
  IF (pt_out < pt_adp) pt_out = pt_adp
  !
  ! Outlet air enthalpy
  zh_out = zh_in - xcpd * (pt_in - pt_out) / zshr
  !
  ! Outlet air humidity ratio
  pq_out = q_fn_t_enth(pt_out, zh_out)
  !
  ! Total thermal energy supplied by the cooling coil
  pt_bld_cool = pm_sys*(zh_in - zh_out)
  !
END IF
!
!
!*      D. HVAC efficiency and electrical power consumed by the DX unit
!          ------------------------------------------------------------
! 
! Energy input ratio modifier curve function of temperature
zeirtemp = za3 + (ztw_in -273.15) * (zb3 + zc3*(ztw_in -273.15))  &
               + (zt_cond-273.15) * (zd3 + ze3*(zt_cond-273.15))  &
               + (ztw_in -273.15) * (zt_cond-273.15) * zf3
!
! HVAC coefficient of performance
pcop = pcop_rat / zeirtemp
!
! Part load fraction correlation
zplr = ph_bld_cool / (pcap_sys * zshr)
!
IF (zplr > 1.0) zplr = 1.0
!
zpartloadf = za5 + zb5 * zplr + zc5 * zplr**2
IF ( zpartloadf < min(0.7, zplr) ) zpartloadf = min(0.7, zplr)
!
! Electrical power consumed by the DX unit
! (compressors plus outdoor condenser fans)
pdx_power = pcap_sys / pcop * zplr / zpartloadf
!
!
!*      E. Waste heat emissions
!          --------------------
!
! Total heat rejected by the condenser
ple_waste = (pt_bld_cool + pdx_power) * pf_water_cond
ph_waste  = (pt_bld_cool + pdx_power) * (1. - pf_water_cond)
!
IF (lhook) CALL dr_hook('DX_AIR_COOLING_COIL_CV',1,zhook_handle)
!
END SUBROUTINE dx_air_cooling_coil_cv