! module module_fr_sfire_phys use module_model_constants, only: cp,xlv use module_fr_sfire_util PRIVATE ! subroutines and functions PUBLIC:: init_fuel_cats,fire_ros,heat_fluxes,set_nfuel_cat,set_fire_params,write_fuels_m PUBLIC::fire_params ! arrays passed to fire_ros type fire_params real,pointer,dimension(:,:):: vx,vy ! wind velocity (m/s) real,pointer,dimension(:,:):: zsf ! terrain height (m) real,pointer,dimension(:,:):: dzdxf,dzdyf ! terrain grad (1) real,pointer,dimension(:,:):: bbb,betafl,phiwc,r_0 ! spread formula coefficients real,pointer,dimension(:,:):: fgip ! init mass of surface fuel (kg/m^2) real,pointer,dimension(:,:):: ischap ! if fuel is chaparral and want rate of spread treated differently end type fire_params ! use as ! type(fire_params)::fp !D in col 2 means quantity derived from the others ! ! Scalar constants (data same for all fuel categories): ! HFGL SURFACE FIRE HEAT FLUX THRESHOLD TO IGNITE CANOPY (W/m^2) ! CMBCNST JOULES PER KG OF DRY FUEL ! FUELHEAT FUEL PARTICLE LOW HEAT CONTENT, BTU/LB ! FUELMC_G FUEL PARTICLE (SURFACE) MOISTURE CONTENT !D BMST RATIO OF LATENT TO SENSIBLE HEAT FROM SFC BURN: ! % of total fuel mass that is water (not quite ! = % fuel moisture). BMST= (H20)/(H20+DRY) ! so BMST = FUELMC_G / (1 + FUELMC_G) where ! FUELMC_G = moisture content of surface fuel ! ! Data arrays indexed by fuel category: ! FGI INITIAL TOTAL MASS OF SURFACE FUEL (KG/M**2) ! FUELDEPTHM FUEL DEPTH, IN M (CONVERTED TO FT) ! SAVR FUEL PARTICLE SURFACE-AREA-TO-VOLUME RATIO, 1/FT ! GRASS: 3500., 10 hr fuel: 109., 100 hr fuel: 30. ! FUELMCE MOISTURE CONTENT OF EXTINCTION; 0.30 FOR MANY DEAD FUELS; 0.15 FOR GRASS ! FUELDENS OVENDRY PARTICLE DENSITY, LB/FT^3 ! ST FUEL PARTICLE TOTAL MINERAL CONTENT ! SE FUEL PARTICLE EFFECTIVE MINERAL CONTENT ! WEIGHT WEIGHTING PARAMETER THAT DETERMINES THE SLOPE OF THE MASS LOSS CURVE ! RANGES FROM ~5 (FAST BURNUP) TO 1000 ( ~40% DECR OVER 10 MIN). ! FCI_D INITIAL DRY MASS OF CANOPY FUEL ! FCT BURN OUT TIME FOR CANOPY FUEL, AFTER DRY (S) ! ichap Set=1 if fuel is chaparral and want the rate of spread treated differently, 0 if not !D FCI INITIAL TOTAL MASS OF CANOPY FUEL !D FCBR FUEL CANOPY BURN RATE (KG/M**2/S) ! ============================================================================= ! Anderson 13 surface fire fuel models, along with some ! estimated canopy properties (for crown fire). ! ============================================================================= ! --- Grass-dominated fuel models ! FUEL MODEL 1: Short grass (1 ft) ! FUEL MODEL 2: Timber (grass and understory) ! FUEL MODEL 3: Tall grass (2.5 ft) ! --- Shrub-dominated fuel models ! FUEL MODEL 4: Chaparral (6 ft) ! FUEL MODEL 5: Brush (2 ft) ! FUEL MODEL 6: Dormant brush, hardwood slash ! FUEL MODEL 7: Southern rough ! --- Forest litter-dominated fuel models ! FUEL MODEL 8: Closed timber litter ! FUEL MODEL 9: Hardwood litter ! FUEL MODEL 10: Timber (litter + understory) ! --- Logging debris-dominated fuel models ! FUEL MODEL 11: Light logging slash ! FUEL MODEL 12: Medium logging slash ! FUEL MODEL 13: Heavy logging slash ! --- Fuel-free ! FUEL MODEL 14: no fuel ! scalar fuel coefficients REAL, SAVE:: cmbcnst,hfgl,fuelmc_g,fuelmc_c ! computed values REAL, SAVE:: bmst,fuelheat ! defaults, may be changed in init_fuel_cats DATA cmbcnst / 17.433e+06/ ! J/kg dry fuel DATA hfgl / 17.e4 / ! W/m^2 DATA fuelmc_g / 0.08 / ! set = 0 for dry surface fuel DATA fuelmc_c / 1.00 / ! set = 0 for dry canopy ! REAL, PARAMETER :: bmst = fuelmc_g/(1+fuelmc_g) ! REAL, PARAMETER :: fuelheat = cmbcnst * 4.30e-04 ! convert J/kg to BTU/lb ! real, parameter :: xlv = 2.5e6 ! to make it selfcontained ! real, parameter :: cp = 7.*287./2 ! to make it selfcontained ! fuel categorytables INTEGER, PARAMETER :: nf=14 ! number of fuel categories in data stmts INTEGER, SAVE :: nfuelcats = 13 ! number of fuel categories that are specified INTEGER, PARAMETER :: mfuelcats = 30 ! allowable number of fuel categories INTEGER, PARAMETER :: zf = mfuelcats-nf ! number of zero fillers in data stmt INTEGER, SAVE :: no_fuel_cat = 14 ! special category outside of 1:nfuelcats CHARACTER (len=80), DIMENSION(mfuelcats ), save :: fuel_name INTEGER, DIMENSION( mfuelcats ), save :: ichap REAL , DIMENSION( mfuelcats ), save :: windrf,weight,fgi,fci,fci_d,fct,fcbr, & fueldepthm,fueldens,fuelmce, & savr,st,se DATA windrf /0.36, 0.36, 0.44, 0.55, 0.42, 0.44, 0.44, & 0.36, 0.36, 0.36, 0.36, 0.43, 0.46, 1e-7, zf*0 / DATA fgi / 0.166, 0.896, 0.674, 3.591, 0.784, 1.344, 1.091, & 1.120, 0.780, 2.692, 2.582, 7.749, 13.024, 1.e-7, zf*0. / DATA fueldepthm /0.305, 0.305, 0.762, 1.829, 0.61, 0.762,0.762, & 0.0610, 0.0610, 0.305, 0.305, 0.701, 0.914, 0.305,zf*0. / DATA savr / 3500., 2784., 1500., 1739., 1683., 1564., 1562., & 1889., 2484., 1764., 1182., 1145., 1159., 3500., zf*0. / DATA fuelmce / 0.12, 0.15, 0.25, 0.20, 0.20, 0.25, 0.40, & 0.30, 0.25, 0.25, 0.15, 0.20, 0.25, 0.12 , zf*0. / DATA fueldens / nf * 32., zf*0. / ! 32 if solid, 19 if rotten. DATA st / nf* 0.0555 , zf*0./ DATA se / nf* 0.010 , zf*0./ ! ----- Notes on weight: (4) - best fit of data from D. Latham (pers. comm.); ! (5)-(7) could be 60-120; (8)-(10) could be 300-1600; ! (11)-(13) could be 300-1600 DATA weight / 7., 7., 7., 180., 100., 100., 100., & 900., 900., 900., 900., 900., 900., 7. , zf*0./ ! ----- 1.12083 is 5 tons/acre. 5-50 tons/acre orig., 100-300 after blowdown DATA fci_d / 0., 0., 0., 1.123, 0., 0., 0., & 1.121, 1.121, 1.121, 1.121, 1.121, 1.121, 0., zf*0./ DATA fct / 60., 60., 60., 60., 60., 60., 60., & 60., 120., 180., 180., 180., 180. , 60. , zf*0. / DATA ichap / 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 , zf*0/ ! ========================================================================= contains subroutine init_fuel_cats implicit none !*** purpose: initialize fuel tables and variables by constants !*** arguments: none logical, external:: wrf_dm_on_monitor !$ integer, external:: OMP_GET_THREAD_NUM !*** local integer:: i,j,k,ii,iounit character(len=128):: msg !*** executable ! read namelist /fuel_scalars/ cmbcnst,hfgl,fuelmc_g,fuelmc_c,nfuelcats,no_fuel_cat namelist /fuel_categories/ fuel_name,windrf,fgi,fueldepthm,savr, & fuelmce,fueldens,st,se,weight,fci_d,fct,ichap !$ if (OMP_GET_THREAD_NUM() .ne. 0)then !$ call crash('init_fuel_cats: must be called from master thread') !$ endif IF ( wrf_dm_on_monitor() ) THEN ! if we are the master task, read the file iounit=open_text_file('namelist.fire','read') read(iounit,fuel_scalars) read(iounit,fuel_categories) CLOSE(iounit) if (nfuelcats>mfuelcats) then write(msg,*)'nfuelcats=',nfuelcats,' is too large, increase mfuelcats' call crash(msg) endif if (no_fuel_cat >= 1 .and. no_fuel_cat <= nfuelcats)then write(msg,*)'no_fuel_cat=',no_fuel_cat,' may not be between 1 and nfuelcats=',nfuelcats call crash(msg) endif ENDIF ! broadcast the contents of the file call wrf_dm_bcast_real(cmbcnst,1) call wrf_dm_bcast_real(hfgl,1) call wrf_dm_bcast_real(fuelmc_g,1) call wrf_dm_bcast_real(fuelmc_c,1) call wrf_dm_bcast_integer(nfuelcats,1) call wrf_dm_bcast_integer(no_fuel_cat,1) call wrf_dm_bcast_real(windrf, nfuelcats) call wrf_dm_bcast_real(fgi, nfuelcats) call wrf_dm_bcast_real(fueldepthm,nfuelcats) call wrf_dm_bcast_real(savr, nfuelcats) call wrf_dm_bcast_real(fuelmce, nfuelcats) call wrf_dm_bcast_real(fueldens, nfuelcats) call wrf_dm_bcast_real(st, nfuelcats) call wrf_dm_bcast_real(se, nfuelcats) call wrf_dm_bcast_real(weight, nfuelcats) call wrf_dm_bcast_real(fci_d, nfuelcats) call wrf_dm_bcast_real(fct, nfuelcats) call wrf_dm_bcast_integer(ichap, nfuelcats) ! compute derived scalars bmst = fuelmc_g/(1+fuelmc_g) fuelheat = cmbcnst * 4.30e-04 ! convert J/kg to BTU/lb ! compute derived fuel category coefficients DO i = 1,nfuelcats fci(i) = (1.+fuelmc_c)*fci_d(i) if(fct(i) .ne. 0.)then fcbr(i) = fci_d(i)/fct(i) ! avoid division by zero else fcbr(i) = 0 endif END DO ! prints call message('**********************************************************') call message('FUEL COEFFICIENTS') write(msg,8)'cmbcnst ',cmbcnst call message(msg) write(msg,8)'hfgl ',hfgl call message(msg) write(msg,8)'fuelmc_g ',fuelmc_g call message(msg) write(msg,8)'fuelmc_c ',fuelmc_c call message(msg) write(msg,8)'bmst ',bmst call message(msg) write(msg,8)'fuelheat ',fuelheat call message(msg) write(msg,7)'nfuelcats ',nfuelcats call message(msg) write(msg,7)'no_fuel_cat',no_fuel_cat call message(msg) j=1 7 format(a,5(1x,i8,4x)) 8 format(a,5(1x,g12.5e2)) 9 format(a,5(1x,a)) do i=1,nfuelcats,j k=min(i+j-1,nfuelcats) call message(' ') write(msg,7)'CATEGORY ',(ii,ii=i,k) call message(msg) write(msg,9)'fuel name ',(fuel_name(ii),ii=i,k) call message(msg) ! write(msg,8)'windrf ',(windrf(ii),ii=i,k) ! call message(msg) write(msg,8)'fgi ',(fgi(ii),ii=i,k) call message(msg) write(msg,8)'fueldepthm',(fueldepthm(ii),ii=i,k) call message(msg) write(msg,8)'savr ',(savr(ii),ii=i,k) call message(msg) write(msg,8)'fuelmce ',(fuelmce(ii),ii=i,k) call message(msg) write(msg,8)'fueldens ',(fueldens(ii),ii=i,k) call message(msg) write(msg,8)'st ',(st(ii),ii=i,k) call message(msg) write(msg,8)'se ',(se(ii),ii=i,k) call message(msg) write(msg,8)'weight ',(weight(ii),ii=i,k) call message(msg) write(msg,8)'fci_d ',(fci_d(ii),ii=i,k) call message(msg) write(msg,8)'fct ',(fct(ii),ii=i,k) call message(msg) write(msg,7)'ichap ',(ichap(ii),ii=i,k) call message(msg) write(msg,8)'fci ',(fci(ii),ii=i,k) call message(msg) write(msg,8)'fcbr ',(fcbr(ii),ii=i,k) call message(msg) enddo call message('**********************************************************') ! and print to file IF ( wrf_dm_on_monitor() ) THEN call write_fuels_m(61,30.,1.) ENDIF end subroutine init_fuel_cats subroutine write_fuels_m(nsteps,maxwind,maxslope) implicit none integer, intent(in):: nsteps ! number of steps for speed computation real, intent(in):: maxwind,maxslope ! computer from zero to these integer:: iounit,k,j,i type(fire_params)::fp !type fire_params !real,pointer,dimension(:,:):: vx,vy ! wind velocity (m/s) !real,pointer,dimension(:,:):: zsf ! terrain height (m) !real,pointer,dimension(:,:):: dzdxf,dzdyf ! terrain grad (1) !real,pointer,dimension(:,:):: bbb,betafl,phiwc,r_0 ! spread formula coefficients !real,pointer,dimension(:,:):: fgip ! init mass of surface fuel (kg/m^2) !real,pointer,dimension(:,:):: ischap ! 1 if chapparal !end type fire_params real, dimension(1:2,1:nsteps), target::vx,vy,zsf,dzdxf,dzdyf,bbb,betafl,phiwc,r_0,fgip,ischap real, dimension(1:2,1:nsteps)::nfuel_cat,fuel_time,ros real::ros_base,ros_wind,ros_slope,propx,propy,r fp%vx=>vx fp%vy=>vy fp%dzdxf=>dzdxf fp%dzdyf=>dzdyf fp%bbb=>bbb fp%betafl=>betafl fp%phiwc=>phiwc fp%r_0=>r_0 fp%fgip=>fgip fp%ischap=>ischap iounit = open_text_file('fuels.m','write') 10 format('fuel(',i3,').',a,'=',"'",a,"'",';% ',a) do k=1,nfuelcats write(iounit,10)k,'fuel_name',trim(fuel_name(k)),'FUEL MODEL NAME' call write_var(k,'windrf',windrf(k),'WIND REDUCTION FACTOR FROM 20ft TO MIDFLAME HEIGHT' ) call write_var(k,'fgi',fgi(k),'INITIAL TOTAL MASS OF SURFACE FUEL (KG/M**2)' ) call write_var(k,'fueldepthm',fueldepthm(k),'FUEL DEPTH (M)') call write_var(k,'savr',savr(k),'FUEL PARTICLE SURFACE-AREA-TO-VOLUME RATIO, 1/FT') call write_var(k,'fuelmce',fuelmce(k),'MOISTURE CONTENT OF EXTINCTION') call write_var(k,'fueldens',fueldens(k),'OVENDRY PARTICLE DENSITY, LB/FT^3') call write_var(k,'st',st(k),'FUEL PARTICLE TOTAL MINERAL CONTENT') call write_var(k,'se',se(k),'FUEL PARTICLE EFFECTIVE MINERAL CONTENT') call write_var(k,'weight',weight(k),'WEIGHTING PARAMETER THAT DETERMINES THE SLOPE OF THE MASS LOSS CURVE') call write_var(k,'fci_d',fci_d(k),'INITIAL DRY MASS OF CANOPY FUEL') call write_var(k,'fct',fct(k),'BURN OUT TIME FOR CANOPY FUEL, AFTER DRY (S)') call write_var(k,'ichap',float(ichap(k)),'1 if chaparral, 0 if not') call write_var(k,'fci',fci(k),'INITIAL TOTAL MASS OF CANOPY FUEL') call write_var(k,'fcbr',fcbr(k),'FUEL CANOPY BURN RATE (KG/M**2/S)') call write_var(k,'hfgl',hfgl,'SURFACE FIRE HEAT FLUX THRESHOLD TO IGNITE CANOPY (W/m^2)') call write_var(k,'cmbcnst',cmbcnst,'JOULES PER KG OF DRY FUEL') call write_var(k,'fuelheat',fuelheat,'FUEL PARTICLE LOW HEAT CONTENT, BTU/LB') call write_var(k,'fuelmc_g',fuelmc_g,'FUEL PARTICLE (SURFACE) MOISTURE CONTENT') call write_var(k,'fuelmc_c',fuelmc_c,'FUEL PARTICLE (CANOPY) MOISTURE CONTENT') ! set up fuel arrays !subroutine set_fire_params( & ! ifds,ifde,jfds,jfde, & ! ifms,ifme,jfms,jfme, & ! ifts,ifte,jfts,jfte, & ! fdx,fdy,nfuel_cat0, & ! nfuel_cat,fuel_time, & ! fp ) nfuel_cat = k call set_fire_params( & 1,2,1,nsteps, & 1,2,1,nsteps, & 1,2,1,nsteps, & 0.,0.,k, & nfuel_cat,fuel_time, & fp ) ! set up windspeed and slope table propx=1. propy=0. do j=1,nsteps r=float(j-1)/float(nsteps-1) ! line 1 varies windspeed (in x direction), zero slope vx(1,j)=maxwind*r vy(1,j)=0. dzdxf(1,j)=0. dzdyf(1,j)=0. ! line 2 varies slope (in x direction), zero slope vx(2,j)=0. vy(2,j)=0. dzdxf(2,j)=maxslope*r dzdyf(2,j)=0. enddo do j=1,nsteps do i=1,2 call fire_ros(ros_base,ros_wind,ros_slope, & propx,propy,i,j,fp) ros(i,j)=ros_base+ros_wind+ros_slope enddo write(iounit,13)k,'wind',j,vx(1,j),'wind speed' write(iounit,13)k,'ros_wind',j,ros(1,j),'rate of spread for the wind speed' write(iounit,13)k,'slope',j,dzdxf(2,j),'slope' write(iounit,13)k,'ros_slope',j,ros(2,j),'rate of spread for the slope' enddo enddo 13 format('fuel(',i3,').',a,'(',i3,')=',g12.5e2,';% ',a) close(iounit) ! stop contains subroutine write_var(k,name,value,descr) ! write entry for one variable integer, intent(in)::k character(len=*), intent(in)::name,descr real, intent(in)::value write(iounit,11)k,name,value write(iounit,12)k,name,descr 11 format('fuel(',i3,').',a,'=',g12.5e2, ';') 12 format('fuel(',i3,').',a,"_descr='",a,"';") end subroutine write_var end subroutine write_fuels_m ! !******************* ! subroutine set_fire_params( & ifds,ifde,jfds,jfde, & ifms,ifme,jfms,jfme, & ifts,ifte,jfts,jfte, & fdx,fdy,nfuel_cat0, & nfuel_cat,fuel_time, & fp ) implicit none !*** purpose: Set all fire model params arrays, constant values. !*** arguments integer, intent(in)::ifds,ifde,jfds,jfde ! fire domain bounds integer, intent(in)::ifts,ifte,jfts,jfte ! fire tile bounds integer, intent(in)::ifms,ifme,jfms,jfme ! memory array bounds real, intent(in):: fdx,fdy ! fire mesh spacing integer,intent(in)::nfuel_cat0 ! default fuel category, if nfuel_cat=0 real, intent(in),dimension(ifms:ifme, jfms:jfme)::nfuel_cat ! fuel data real, intent(out), dimension(ifms:ifme, jfms:jfme)::fuel_time ! fire params arrays type(fire_params),intent(inout)::fp !*** local real:: fuelload, fueldepth, rtemp1, rtemp2, & qig, epsilon, rhob, wn, betaop, e, c, & xifr, etas, etam, a, gammax, gamma, ratio, ir, & fuelloadm,fdxinv,fdyinv integer:: i,j,k integer::nerr character(len=128)::msg !*** executable nerr=0 do j=jfts,jfte do i=ifts,ifte ! fuel category k=int( nfuel_cat(i,j) ) if(k.eq.no_fuel_cat)then ! no fuel fp%fgip(i,j)=0. ! no mass fp%ischap(i,j)=0. fp%betafl(i,j)=0. ! to prevent division by zero fp%bbb(i,j)=1. ! fuel_time(i,j)=7./0.85 ! does not matter, just what was there before fp%phiwc(i,j)=0. fp%r_0(i,j)=0. ! no fuel, no spread. else if(k.eq.0.and.nfuel_cat0.ge.1.and.nfuel_cat0.le.nfuelcats)then ! replace k=0 by default k=nfuel_cat0 nerr=nerr+1 endif if(k.lt.1.or.k.gt.nfuelcats)then !$OMP CRITICAL(SFIRE_PHYS_CRIT) write(msg,'(3(a,i5))')'nfuel_cat(', i ,',',j,')=',k !$OMP END CRITICAL(SFIRE_PHYS_CRIT) call message(msg) call crash('set_fire_params: fuel category out of bounds') endif fuel_time(i,j)=weight(k)/0.85 ! cell based ! set fuel time constant: weight=1000 => 40% decrease over 10 min ! fuel decreases as exp(-t/fuel_time) ! exp(-600*0.85/1000) = approx 0.6 fp%ischap(i,j)=ichap(k) fp%fgip(i,j)=fgi(k) ! ...Settings of fire spread parameters from Rothermel follows. These ! don't need to be recalculated later. fuelloadm= (1.-bmst) * fgi(k) ! fuelload without moisture fuelload = fuelloadm * (.3048)**2 * 2.205 ! to lb/ft^2 fueldepth = fueldepthm(k)/0.3048 ! to ft fp%betafl(i,j) = fuelload/(fueldepth * fueldens(k))! packing ratio betaop = 3.348 * savr(k)**(-0.8189) ! optimum packing ratio qig = 250. + 1116.*fuelmc_g ! heat of preignition, btu/lb epsilon = exp(-138./savr(k) ) ! effective heating number rhob = fuelload/fueldepth ! ovendry bulk density, lb/ft^3 c = 7.47 * exp( -0.133 * savr(k)**0.55) ! const in wind coef fp%bbb(i,j) = 0.02526 * savr(k)**0.54 ! const in wind coef e = 0.715 * exp( -3.59e-4 * savr(k)) ! const in wind coef fp%phiwc(i,j) = c * (fp%betafl(i,j)/betaop)**(-e) rtemp2 = savr(k)**1.5 gammax = rtemp2/(495. + 0.0594*rtemp2) ! maximum rxn vel, 1/min a = 1./(4.774 * savr(k)**0.1 - 7.27) ! coef for optimum rxn vel ratio = fp%betafl(i,j)/betaop gamma = gammax *(ratio**a) *exp(a*(1.-ratio)) !optimum rxn vel, 1/min wn = fuelload/(1 + st(k)) ! net fuel loading, lb/ft^2 rtemp1 = fuelmc_g/fuelmce(k) etam = 1.-2.59*rtemp1 +5.11*rtemp1**2 -3.52*rtemp1**3 !moist damp coef etas = 0.174* se(k)**(-0.19) ! mineral damping coef ir = gamma * wn * fuelheat * etam * etas !rxn intensity,btu/ft^2 min ! irm = ir * 1055./( 0.3048**2 * 60.) * 1.e-6 !for mw/m^2 xifr = exp( (0.792 + 0.681*savr(k)**0.5) & * (fp%betafl(i,j)+0.1)) /(192. + 0.2595*savr(k)) ! propagating flux ratio ! ... r_0 is the spread rate for a fire on flat ground with no wind. fp%r_0(i,j) = ir*xifr/(rhob * epsilon *qig) ! default spread rate in ft/min endif enddo enddo if(nerr.gt.1)then !$OMP CRITICAL(SFIRE_PHYS_CRIT) write(msg,'(a,i6,a)')'set_fire_params: WARNING: fuel category 0 replaced in',nerr,' cells' !$OMP END CRITICAL(SFIRE_PHYS_CRIT) call message(msg) endif end subroutine set_fire_params ! !******************* ! subroutine heat_fluxes(dt, & ifms,ifme,jfms,jfme, & ! memory dims ifts,ifte,jfts,jfte, & ! tile dims iffs,iffe,jffs,jffe, & ! fuel_frac_burnt dims fgip,fuel_frac_burnt, & !in grnhft,grnqft) !out implicit none !*** purpose ! compute the heat fluxes on the fire grid cells !*** arguments real, intent(in)::dt ! dt the fire time step (the fire model advances time by this) integer, intent(in)::ifts,ifte,jfts,jfte,ifms,ifme,jfms,jfme,iffs,iffe,jffs,jffe ! dimensions real, intent(in),dimension(ifms:ifme,jfms:jfme):: fgip real, intent(in),dimension(iffs:iffe,jffs:jffe):: fuel_frac_burnt real, intent(out),dimension(ifms:ifme,jfms:jfme):: grnhft,grnqft !*** local integer::i,j real:: dmass !*** executable do j=jfts,jfte do i=ifts,ifte dmass = & ! surface fuel dry mass burnt this call (kg/m^2) fgip(i,j) & ! init mass from fuel model no (kg/m^2) = fgi(nfuel_cat(i,j) * fuel_frac_burnt(i,j) ! fraction burned this call (1) grnhft(i,j) = (dmass/dt)*(1.-bmst)*cmbcnst ! surface fire sensible heat flux W/m^2 grnqft(i,j) = (bmst+(1.-bmst)*.56)*(dmass/dt)*xlv ! surface fire latent heat flux W/m ! xlv is defined in module_model_constants.. Assume 56% of cellulose molecule mass is water. enddo enddo end subroutine heat_fluxes ! !********************** ! subroutine set_nfuel_cat( & ifms,ifme,jfms,jfme, & ifts,ifte,jfts,jfte, & ifuelread,nfuel_cat0,zsf,nfuel_cat) implicit none ! set fuel distributions for testing integer, intent(in):: ifts,ifte,jfts,jfte, & ifms,ifme,jfms,jfme integer, intent(in)::ifuelread,nfuel_cat0 real, intent(in), dimension(ifms:ifme, jfms:jfme)::zsf real, intent(out), dimension(ifms:ifme, jfms:jfme)::nfuel_cat !*** local ! parameters to control execution integer:: i,j,iu1 real:: t1 character(len=128)msg !$OMP CRITICAL(SFIRE_PHYS_CRIT) write(msg,'(a,i3)')'set_nfuel_cat: ifuelread=',ifuelread !$OMP END CRITICAL(SFIRE_PHYS_CRIT) call message(msg) if (ifuelread .eq. -1 .or. ifuelread .eq. 2) then !$OMP CRITICAL(SFIRE_PHYS_CRIT) call message('set_nfuel_cat: assuming nfuel_cat initialized already') call message(msg) !$OMP END CRITICAL(SFIRE_PHYS_CRIT) else if (ifuelread .eq. 0) then ! do j=jfts,jfte do i=ifts,ifte nfuel_cat(i,j)=real(nfuel_cat0) enddo enddo !$OMP CRITICAL(SFIRE_PHYS_CRIT) write(msg,'(a,i3)')'set_nfuel_cat: fuel initialized with category',nfuel_cat0 !$OMP END CRITICAL(SFIRE_PHYS_CRIT) call message(msg) else if (ifuelread .eq. 1) then ! ! make dependent on altitude (co mountains/forest vs. plains) ! 2000 m : 6562 ft ; 1600 m: 5249 ft ! ... user defines fuel category spatial variability ! param! do j=jfts,jfte do i=ifts,ifte ! nfuel_cat(i,j)= 2 ! grass with understory ! jm does nothing !jm t1=zsf(i,j)*slngth/100. t1 = zsf(i,j) ! this is in m if(t1.le.1524.)then ! up to 5000 ft nfuel_cat(i,j)= 3 ! tall grass else if(t1.ge.1524. .and. t1.le.2073.)then ! 5.0-6.8 kft. nfuel_cat(i,j)= 2 ! grass with understory else if(t1.ge.2073..and.t1.le.2438.)then ! 6.8-8.0 kft. nfuel_cat(i,j)= 8 ! timber litter - 10 (ponderosa) else if(t1.gt.2438. .and. t1.le. 3354.) then ! 8.0-11.0 kft. ! ... could also be mixed conifer. nfuel_cat(i,j)= 10 ! timber litter - 8 (lodgepole) else if(t1.gt.3354. .and. t1.le. 3658.) then ! 11.0-12.0 kft nfuel_cat(i,j)= 1 ! alpine meadow - 1 else if(t1.gt.3658. ) then ! > 12.0 kft nfuel_cat(i,j)= 14 ! no fuel. endif enddo enddo call message('set_nfuel_cat: fuel initialized by altitude') else call crash('set_nfuel_cat: bad ifuelread') endif ! .............end load fuel categories (or constant) here. end subroutine set_nfuel_cat ! !********************** ! subroutine fire_ros(ros_base,ros_wind,ros_slope, & propx,propy,i,j,fp) implicit none ! copied with the following changes ONLY: ! 0.5*(speed + abs(speed)) -> max(speed,0.) ! index l -> j ! not using nfuel_cat here - cell info was put into arrays passed as arguments ! in include file to avoid transcription errors when used elsewhere ! betaop is absorbed in phiwc, see module_fr_sfire_model/fire_startup ! return the base, wind, and slope contributions to the rate of spread separately ! because they may be needed to take advantage of known wind and slope vectors. ! They should add up to get the total rate of spread. !ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc ! ... calculates fire spread rate with McArthur formula or Rothermel ! using fuel type of fuel cell ! ! m/s =(ft/min) *.3048/60. =(ft/min) * .00508 ! conversion rate ! ft/min = m/s * 2.2369 * 88. = m/s * 196.850 ! conversion rate ! !ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc !*** arguments real, intent(out)::ros_base,ros_wind,ros_slope ! rate of spread contribution due to fuel, wind, and slope real, intent(in)::propx,propy integer, intent(in)::i,j ! node mesh coordinates type(fire_params),intent(in)::fp !*** local real:: speed, tanphi ! windspeed and slope in the direction normal to the fireline real:: umid, phis, phiw, spdms, umidm, excess real:: ros_back integer, parameter::ibeh=1 real, parameter::ros_max=6. character(len=128)msg real::cor_wind,cor_slope,nvx,nvy,scale !*** executable ! make sure normal direction is size 1 !scale=sqrt(propx*propx+propy*propy)+tiny(scale) scale=1. nvx=propx/scale nvy=propy/scale if (fire_advection.ne.0) then ! from flags in module_fr_sfire_util ! wind speed is total speed speed = sqrt(fp%vx(i,j)*fp%vx(i,j)+ fp%vy(i,j)*fp%vy(i,j))+tiny(speed) ! slope is total slope tanphi = sqrt(fp%dzdxf(i,j)*fp%dzdxf(i,j) + fp%dzdyf(i,j)*fp%dzdyf(i,j))+tiny(tanphi) ! cos of wind and spread, if >0 cor_wind = max(0.,(fp%vx(i,j)*nvx + fp%vy(i,j)*nvy)/speed) ! cos of slope and spread, if >0 cor_slope = max(0., (fp%dzdxf(i,j)*nvx + fp%dzdyf(i,j)*nvy)/tanphi) else ! wind speed in spread direction speed = fp%vx(i,j)*nvx + fp%vy(i,j)*nvy ! slope in spread direction tanphi = fp%dzdxf(i,j)*nvx + fp%dzdyf(i,j)*nvy cor_wind=1. cor_slope=1. endif if (.not. fp%ischap(i,j) > 0.) then ! if fuel is not chaparral, calculate rate of spread one of these ways if (ibeh .eq. 1) then ! use Rothermel formula ! ... if wind is 0 or into fireline, phiw = 0, &this reduces to backing ros. spdms = max(speed,0.) ! umidm = min(spdms,30.) ! max input wind spd is 30 m/s !param! umid = umidm * 196.850 ! m/s to ft/min ! eqn.: phiw = c * umid**bbb(i,j) * (fp%betafl(i,j)/betaop)**(-e) ! wind coef phiw = umid**fp%bbb(i,j) * fp%phiwc(i,j) ! wind coef phis=0. if (tanphi .gt. 0.) then phis = 5.275 *(fp%betafl(i,j))**(-0.3) *tanphi**2 ! slope factor endif ! rosm = fp%r_0(i,j)*(1. + phiw + phis) * .00508 ! spread rate, m/s ros_base = fp%r_0(i,j) * .00508 ros_wind = ros_base*phiw ros_slope= ros_base*phis else ! McArthur formula (Australian) ! rosm = 0.18*exp(0.8424*max(speed,0.)) ros_base = 0.18*exp(0.8424) ros_wind = 0.18*exp(0.8424*max(speed,0.)) ros_slope =0. endif ! else ! chaparral ! .... spread rate has no dependency on fuel character, only windspeed. spdms = max(speed,0.) ! rosm = 1.2974 * spdms**1.41 ! spread rate, m/s ! note: backing ros is 0 for chaparral without setting nozero value below !sp_n=.03333 ! chaparral backing fire spread rate 0.033 m/s ! param! !rosm= max(rosm, sp_n) ! no less than backing r.o.s. ros_back=.03333 ! chaparral backing fire spread rate 0.033 m/s ! param! ros_wind = 1.2974 * spdms**1.41 ! spread rate, m/s ros_wind = max(ros_wind, ros_back) ros_slope =0. endif ! if advection, multiply by the cosines ros_wind=ros_wind*cor_wind ros_slope=ros_slope*cor_slope ! ! ----------note! put an 6 m/s cap on max spread rate ----------- ! rosm= min(rosm, 6.) ! no faster than this cap ! param ! excess = ros_base + ros_wind + ros_slope - ros_max if (excess > 0.)then ! take it out of wind and slope in proportion ros_wind = ros_wind - excess*ros_wind/(ros_wind+ros_slope) ros_slope = ros_slope - excess*ros_slope/(ros_wind+ros_slope) endif !write(msg,*)i,j,' speed=',speed,' tanphi',tanphi,' ros=',ros_base,ros_wind,ros_slope !call message(msg) return contains real function nrm2(u,v) real, intent(in)::u,v nrm2=sqrt(u*u+v*v) end function nrm2 end subroutine fire_ros end module module_fr_sfire_phys