!------------------------------------------------------------------------------ ! Harvard University Atmospheric Chemistry Modeling Group ! !------------------------------------------------------------------------------ !BOP ! ! !MODULE: apm_grow_mod ! ! !DESCRIPTION: Module APM\_GROW\_MOD contains variables and routines for ! computing size-resolved particle growth. !\\ !\\ ! !INTERFACE: ! MODULE APM_GROW_MOD ! ! !USES: ! IMPLICIT NONE PRIVATE ! ! !PUBLIC MEMBER FUNCTIONS: ! PUBLIC :: APM_GROW PUBLIC :: APM_MOVEBIN ! !REVISION HISTORY: ! 23 Aug 2008 - F. Yu - Initial version ! 08 Nov 2010 - R. Yantosca - Added ProTeX headers !EOP !------------------------------------------------------------------------------ !BOC CONTAINS !EOC !------------------------------------------------------------------------------ ! Harvard University Atmospheric Chemistry Modeling Group ! !------------------------------------------------------------------------------ !BOP ! ! !IROUTINE: apm_grow ! ! !DESCRIPTION: Subroutine APM\_GROW calculates H2SO4 condensational growth ! of aerosol particles !\\ !\\ ! !INTERFACE: ! SUBROUTINE APM_GROW( ICOND, NSO4, TK, & PRESS, CCOND, PCOND, & TCSOTHER, DTNG, XN, & XVA, RWETCM, TOTCONDOTHER, & XMCOND ) ! ! !USES: ! USE APM_INIT_MOD, ONLY: DENSULF, RDRY USE APM_INIT_MOD, ONLY: ONEPI, BK, AVG, RGAS ! ! !INPUT/OUTPUT PARAMETERS: ! INTEGER :: NSO4 ! Dimension variable REAL*8 :: TK ! Temperature (K) REAL*8 :: PRESS ! Pressure (pa) REAL*8 :: PCOND ! Condensable vapor production rate (#/cm3s) REAL*8 :: DTNG ! Time detp for growth (s) REAL*8 :: XN(NSO4) ! Number conc of each bin (#/cm3) REAL*8 :: XVA(NSO4) ! Total acid volume of each bin (cm3/cm3) ! ! !INPUT/OUTPUT PARAMETERS: ! INTEGER :: ICOND REAL*8 :: CCOND ! Condensable vapor concentration (#/cm3) REAL*8 :: TCSOTHER REAL*8 :: RWETCM(NSO4) REAL*8 :: TOTCONDOTHER REAL*8 :: XMCOND ! ! !REMARKS: ! Output: ! updated XMA, CCOND ! ! !REVISION HISTORY: ! 17 Mar 2010 - F. Yu - Initial version ! 08 Nov 2010 - R. Yantosca - Added ProTeX headers !EOP !------------------------------------------------------------------------------ !BOC ! ! !LOCAL VARIABLES: ! INTEGER :: N, NMAX REAL*8 :: XMA(NSO4) REAL*8 :: YF(NSO4),YGR(NSO4),AKELV(NSO4) REAL*8 :: CSCOND,YFSUM1 REAL*8 :: V1COND,VCOND,TEMP0,WTGAS REAL*8 :: WTAIR,DIAMAIR,RHOA,CDIFUS,CDIFUS2,DIFUSC,FREEPD REAL*8 :: YY,YKN,FCORR,TEMP1,YFSUM,YEVAP REAL*8 :: YEVAPV,CCOND1,CCONDA,TOTEVAP,YGRSUM,YDV,TOTCOND REAL*8 :: XRCM REAL*8 :: DENCOND,AKELV0,SURFT,YTEMP1 REAL*8 :: DVA(NSO4) !================================================================= ! APM_GROW begins here! !================================================================= ! DENCOND = DENSULF IF(ICOND.EQ.1) THEN !H2SO4 CSCOND = 1.E4 ! no acid evap now AKELV0 = CCOND/CSCOND IF(AKELV0.LT.1.2) RETURN AKELV =1. ELSE WRITE(6,*)"NEED to check ICOND value" STOP ENDIF V1COND = XMCOND/(AVG*DENCOND) ! volume of one molecule (cm3) VCOND = SQRT(8.*RGAS*TK/(ONEPI*XMCOND)) ! cm/s TEMP0 = VCOND * XMCOND/AVG *ONEPI ! Cal. gas diffusion coef. and mean free path ! WTGAS = XMCOND WTAIR = 28.966 DIAMAIR = 4.5E-08 RHOA = WTAIR*PRESS*10./(RGAS*TK) ! AIR DENSITY (G CM-3) CDIFUS =3.*SQRT(0.5*RGAS*WTAIR/ONEPI)/(AVG*8.*DIAMAIR**2) CDIFUS2=CDIFUS * SQRT((WTGAS+WTAIR)/WTGAS) DIFUSC=CDIFUS2 * SQRT(TK)/RHOA FREEPD = 3.*DIFUSC/VCOND ! YF = 0. YFSUM = 0. YY = PCOND DO N = 1, NSO4 XRCM = RWETCM(N) ! RWETCM in cm YKN = FREEPD/XRCM FCORR = YKN/(0.75+YKN) TEMP1 = TEMP0*FCORR IF(AKELV(N).LT.AKELV0) THEN TEMP1 = TEMP1 *(1.-AKELV(N)/AKELV0) ELSE TEMP1 = 0. ! no evapor for now ENDIF YF(N) = TEMP1 * XN(N) *XRCM*XRCM/(DENCOND*V1COND) ! s-1 YFSUM = YFSUM + YF(N) ! YEVAP = CSCOND*AKELV*YF(N) ! in #/cm3s ! YEVAPV = YEVAP*DTNG*V1COND ! in cm3/cm3 ! IF(YEVAPV.GT. XVA(N)) THEN ! YEVAP = XVA(N)/(DTNG*V1COND) ! ENDIF ! YY = YY + YEVAP ENDDO IF(YFSUM.EQ.0.) THEN WRITE(6,100)AKELV0,(AKELV(N),N=1,NSO4,5) WRITE(6,100)FCORR,(YF(N),N=1,NSO4,5) STOP ENDIF ! Consider scavenging of H2SO4 vapor by aerosols other than sulfate YFSUM1 = YFSUM + TCSOTHER CCOND1 = YY/YFSUM1 + (CCOND - YY/YFSUM1)*exp(-YFSUM1*DTNG) CCONDA = 0.5 * (CCOND1 + CCOND) TOTEVAP = 0. ! YGRSUM = 0. ! DO N = 1, NSO4 ! YGR(N) = YF(N)*(CCONDA - CSCOND*AKELV) ! IF(YGR(N).LT.0.) THEN ! YDV = -YGR(N)*DTNG*V1COND !cm3 ! IF(YDV.GT.XVA(N)) THEN ! TOTEVAP = TOTEVAP + XVA(N) ! XVA(N) = 1.E-50 ! ELSE ! XVA(N) = XVA(N) - YDV ! TOTEVAP = TOTEVAP + YDV ! ENDIF ! ELSE ! YGRSUM = YGRSUM + YGR(N) ! ENDIF ! ENDDO ! TOTCOND=PCOND*DTNG+(CCOND-CCOND1)+TOTEVAP/V1COND ! #/cm3 ! H2SO4 vapor condensing on particles other than sulfate TOTCONDOTHER = TOTCOND * (1.-YFSUM/YFSUM1) ! H2SO4 vapor condensing on sulfate TOTCOND = TOTCOND * YFSUM/YFSUM1 YGR = YF YGRSUM = YFSUM DO N = 1, NSO4 DVA(N) = TOTCOND*V1COND*YGR(N)/YGRSUM XVA(N)=XVA(N)+DVA(N) ENDDO 100 FORMAT(20(1PE9.2)) ! ! Update gas concentration CCOND = CCOND1 END SUBROUTINE APM_GROW !EOC !------------------------------------------------------------------------------ ! Harvard University Atmospheric Chemistry Modeling Group ! !------------------------------------------------------------------------------ !BOP ! ! !IROUTINE: apm_movebin ! ! !DESCRIPTION: Subroutine APM\_MOVEBIN moves particles across bins after ! growth. !\\ !\\ ! !INTERFACE: ! SUBROUTINE APM_MOVEBIN( NSO4, XN, XVA ) ! ! !USES: ! USE APM_INIT_MOD, ONLY: VDRY ! ! !INPUT PARAMETERS: ! INTEGER :: NSO4 ! Dimension for arrays ! ! !INPUT/OUTPUT PARAMETERS: ! REAL*8 :: XN(NSO4) ! Number conc of each bin (#/cm3) REAL*8 :: XVA(NSO4) ! Total acid mass of each bin (cm3/cm3) ! ! !REVISION HISTORY: ! 17 Mar 2010 - F. Yu - Initial version ! 08 Nov 2010 - R. Yantosca - Added ProTeX headers !EOP !------------------------------------------------------------------------------ !BOC ! ! !DEFINED PARAMETERS: ! ! Number of core component associated with particles, set to 1 now, ! may increase later INTEGER, PARAMETER :: NC = 1 ! ! !LOCAL VARIABLES: ! INTEGER :: N, NMAX, IC, J, J0, J1, JS REAL*8 :: YN(NSO4),YVA(NSO4,NC),YC(NSO4,NC) REAL*8 :: XVT, VDA, YFR, YFV NMAX = NSO4 ! ! Move the partilces across bins due to the condensation/evap ! DO N=1,NMAX YVA(N,1) = XVA(N) ! to be modified if NC>1 ENDDO DO n=1,NMAX YN(n)=1.E-20 DO IC=1,NC YC(n,IC)=1./float(NC)*YN(n)*VDRY(n)*1.E6 ! in cm3/cm3 ENDDO ! IF(YN(n).GT.1.E6.or.YN(n).LE.0.) THEN ! WRITE(6,*)"4 XN=",n,YN(n),XN(n),YC(n,1) ! ENDIF ENDDO DO n=1,NMAX XVT = 0. DO IC=1,NC XVT = XVT + YVA(n,IC) ! cm3/cm3 ENDDO VDA = XVT/XN(n)*1.E-6 ! in m3 ! if particles become smaller than first bin or larger than last bin, ! scale and put in the first or last bin in a fashion that conserve mass IF(VDA.LT.VDRY(1)) THEN YN(1) = YN(1) + XN(n)*VDA/VDRY(1) DO IC=1,NC ! move compositions YC(1,IC) = YC(1,IC)+YVA(n,IC) ENDDO ! IF(YN(n).GT.1.E6.or.YN(n).LE.0.) THEN ! WRITE(6,*)"41 XN=",n,YN(n),XN(n),YC(n,1),YVA(n,1),XVT,VDA ! ENDIF ELSEIF(VDA.GT.VDRY(NMAX)) THEN YN(NMAX) = YN(NMAX) + XN(n)*VDA/VDRY(NMAX) DO IC=1,NC ! move compositions YC(NMAX,IC) = YC(NMAX,IC)+YVA(n,IC) ENDDO ! IF(YN(n).GT.1.E6.or.YN(n).LE.0.) THEN ! WRITE(6,*)"42 XN=",n,YN(n),XN(n),YC(n,1), ! & XVA(n),YVA(n,1),XVT,VDA ! ENDIF ELSE IF(VDA.GE.VDRY(n)) THEN J0=n J1 = NMAX-1 JS = 1 ELSE J0=n-1 J1=1 JS=-1 ENDIF DO J=J0,J1,JS IF(VDA.GE.VDRY(J).AND.VDA.LT.VDRY(J+1)) THEN YFR = (VDRY(J+1)-VDA)/(VDRY(J+1)-VDRY(J)) YFV = YFR*VDRY(J)/VDA YN(J) = YN(J) + YFR*XN(n) !move # YN(J+1)=YN(J+1)+(1.-YFR)*XN(n) DO IC=1,NC ! move compositions YC(J,IC) = YC(J,IC)+YFV*YVA(n,IC) YC(J+1,IC)=YC(J+1,IC) & +(1.-YFV)*YVA(n,IC) ENDDO GOTO 160 ENDIF ENDDO ENDIF 160 CONTINUE ENDDO ! Update the bin values DO n=1,NMAX IF(YN(n).GT.1.E6.or.YN(n).LE.0.) THEN WRITE(6,*)"5 XN=",n,YN(n),XN(n),YC(n,1) ENDIF XN(n) = YN(n) DO IC=1,NC YVA(n,IC) =YC(n,IC) ENDDO XVA(N) = YVA(n,1) ! to be modified if NC>1 ENDDO END SUBROUTINE APM_MOVEBIN !EOC END MODULE APM_GROW_MOD