temp_change.cpp

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/* This file is part of Cloudy and is copyright (C)1978-2017 by Gary J. Ferland and
 * others.  For conditions of distribution and use see copyright notice in license.txt */
/*tfidle update some temperature dependent variables */
/*tauff compute optical depth where cloud is thin to free-free and plasma freq */
#include "cddefines.h"
#include "conv.h"
#include "opacity.h"
#include "dense.h"
#include "phycon.h"
#include "stopcalc.h"
#include "trace.h"
#include "rfield.h"
#include "doppvel.h"
#include "radius.h"
#include "wind.h"
#include "thermal.h"
#include "vectorize.h"

/*tauff compute optical depth where cloud is thin to free-free and plasma freq */
STATIC void tauff();
/* On first run, fill GauntFF with gaunt factors        */

STATIC void tfidle(
                        bool lgForceUpdate);

void TempChange(
                         double TempNew ,
                         /* option to force update of all variables */
                         bool lgForceUpdate)
{

        DEBUG_ENTRY( "TempChange()" );

        /* set new temperature */
        if( TempNew > phycon.TEMP_LIMIT_HIGH )
        {
                /* temp is too high */
                fprintf(ioQQQ," PROBLEM DISASTER - the kinetic temperature, %.3eK,"
                        " is above the upper limit of the code, %.3eK.\n",
                        TempNew , phycon.TEMP_LIMIT_HIGH );
                fprintf(ioQQQ," This calculation is aborting.\n Sorry.\n");

                TempNew = phycon.TEMP_LIMIT_HIGH*0.99999;
                lgAbort = true;
        }
        else if( TempNew < phycon.TEMP_LIMIT_LOW )
        {
                /* temp is too low */
                fprintf(ioQQQ," PROBLEM DISASTER - the kinetic temperature, %.3eK,"
                        " is below the lower limit of the code, %.3eK.\n",
                        TempNew , phycon.TEMP_LIMIT_LOW );
                fprintf(ioQQQ," Consider setting a lowest temperature with the SET TEMPERATURE FLOOR command.\n");
                fprintf(ioQQQ," This calculation is aborting.\n Sorry.\n");
                TempNew = phycon.TEMP_LIMIT_LOW*1.00001;
                lgAbort = true;
        }
        else if( TempNew < StopCalc.TeFloor )
        {
                if( trace.lgTrace || trace.nTrConvg>=2  )
                        fprintf(ioQQQ,"temp_change: temp change floor hit, TempNew=%.3e TeFloor=%.3e, "
                                        "setting constant temperature, nTotalIoniz=%li\n",
                                         TempNew , StopCalc.TeFloor , conv.nTotalIoniz);
                /* temperature floor option  -
                 * go to constant temperature calculation if temperature
                 * falls below floor */
                thermal.lgTemperatureConstant = true;
                thermal.ConstTemp = (realnum)StopCalc.TeFloor;
                phycon.te = thermal.ConstTemp;
                /*fprintf(ioQQQ,"DEBUG TempChange hit temp floor, setting const temp to %.3e\n",
                        phycon.te );*/
        }
        else
        {
                /* temp is within range */
                phycon.te = TempNew;
        }

        /* now update related variables */
        tfidle( lgForceUpdate );
        return;
}
void TempChange(
                                double TempNew )
{

        DEBUG_ENTRY( "TempChange()" );

        /* set new temperature */
        if( TempNew > phycon.TEMP_LIMIT_HIGH )
        {
                /* temp is too high */
                fprintf(ioQQQ," PROBLEM DISASTER - the kinetic temperature, %.3eK,"
                        " is above the upper limit of the code, %.3eK.\n",
                        TempNew , phycon.TEMP_LIMIT_HIGH );
                fprintf(ioQQQ," This calculation is aborting.\n Sorry.\n");

                TempNew = phycon.TEMP_LIMIT_HIGH*0.99999;
                lgAbort = true;
        }
        else if( TempNew < phycon.TEMP_LIMIT_LOW )
        {
                /* temp is too low */
                fprintf(ioQQQ," PROBLEM DISASTER - the kinetic temperature, %.3eK,"
                        " is below the lower limit of the code, %.3eK.\n",
                        TempNew , phycon.TEMP_LIMIT_LOW );
                fprintf(ioQQQ," Consider setting a lowest temperature with the SET TEMPERATURE FLOOR command.\n");
                fprintf(ioQQQ," This calculation is aborting.\n Sorry.\n");
                TempNew = phycon.TEMP_LIMIT_LOW*1.00001;
                lgAbort = true;
        }
        else
        {
                /* temp is within range */
                phycon.te = TempNew;
        }

        /* now update related variables */
        tfidle( false );
        return;
}

void tfidle(
        /* option to force update of all variables */
        bool lgForceUpdate)
{
        static double tgffused=-1.;
        static double ttused = 0.;
        static bool lgZLogSet = false;

        DEBUG_ENTRY( "tfidle()" );

        /* called with lgForceUpdate true in zero.c, when we must update everything */
        if( lgForceUpdate )
        {
                ttused = -1.;
                tgffused = -1.;
        }

        /* check that eden not negative */
        if( dense.eden <= 0. )
        {
                fprintf( ioQQQ, "tfidle called with a zero or negative electron density,%10.2e\n", 
                  dense.eden );
                TotalInsanity();
        }

        /* check that temperature not negative */
        if( phycon.te <= 0. )
        {
                fprintf( ioQQQ, "tfidle called with a negative electron temperature,%10.2e\n", 
                  phycon.te );
                TotalInsanity();
        }

        /* one time only, set up array of logs of charge squared */
        if( !lgZLogSet )
        {
                for( long nelem=0; nelem<LIMELM; ++nelem )
                {
                        /* this array is used to modify the log temperature array
                         * defined below, for hydrogenic species of charge nelem+1 */
                        phycon.sqlogz[nelem] = log10( POW2(nelem+1.) );
                }
                lgZLogSet = true;
        }

        if( ! fp_equal( phycon.te, ttused ) )
        {
                ttused = phycon.te;
                thermal.te_update = phycon.te;
                /* current temperature in various units */
                phycon.te_eV = phycon.te/EVDEGK;
                phycon.te_ryd = phycon.te/TE1RYD;
                phycon.te_wn = phycon.te / T1CM;

                phycon.tesqrd = POW2(phycon.te);
                phycon.sqrte = sqrt(phycon.te);
                thermal.halfte = 0.5/phycon.te;
                thermal.tsq1 = 1./phycon.tesqrd;
                phycon.te32 = phycon.te*phycon.sqrte;
                phycon.teinv = 1./phycon.te;

                phycon.alogte = log10(phycon.te);
                phycon.alnte = log(phycon.te);

                phycon.telogn[0] = phycon.alogte;
                for( int i=1; i < 7; i++ )
                {
                        phycon.telogn[i] = phycon.telogn[i-1]*phycon.telogn[0];
                }

                phycon.te10 = pow(phycon.te,0.10);
                phycon.te20 = phycon.te10 * phycon.te10;
                phycon.te30 = phycon.te20 * phycon.te10;
                phycon.te40 = phycon.te30 * phycon.te10;
                phycon.te70 = phycon.sqrte * phycon.te20;
                phycon.te90 = phycon.te70 * phycon.te20;

                phycon.te01 = pow(phycon.te,0.01);
                phycon.te02 = phycon.te01 * phycon.te01;
                phycon.te03 = phycon.te02 * phycon.te01;
                phycon.te04 = phycon.te02 * phycon.te02;
                phycon.te05 = phycon.te03 * phycon.te02;
                phycon.te07 = phycon.te05 * phycon.te02;

                phycon.te001 = pow(phycon.te,0.001);
                phycon.te002 = phycon.te001 * phycon.te001;
                phycon.te003 = phycon.te002 * phycon.te001;
                phycon.te004 = phycon.te002 * phycon.te002;
                phycon.te005 = phycon.te003 * phycon.te002;
                phycon.te007 = phycon.te005 * phycon.te002;
                /*>>>chng 06 June 30 -Humeshkar Nemala*/
                phycon.te0001 = pow(phycon.te ,0.0001);
                phycon.te0002 = phycon.te0001 * phycon.te0001;
                phycon.te0003 = phycon.te0002 * phycon.te0001;
                phycon.te0004 = phycon.te0002 * phycon.te0002;
                phycon.te0005 = phycon.te0003 * phycon.te0002;
                phycon.te0007 = phycon.te0005 * phycon.te0002;

        }

        /* >>>chng 99 nov 23, removed this line, so back to old method of h coll */
        /* used for hydrogenic collisions */
        /* 
         * following electron density has approximate correction for neutrals
         * corr of hi*1.7e-4 accounts for col ion by HI; 
         * >>refer      H0      correction for collisional contribution         Drawin, H.W. 1969, Zs Phys 225, 483.
         * also quoted in Dalgarno & McCray 1972
         * extensive discussion of this in 
         *>>refer       H0      collisions      Lambert, D.L. 
         * used EdenHCorr instead
         * edhi = eden + hi * 1.7e-4
         */
        dense.EdenHCorr = dense.eden + 
                /* dense.HCorrFac is unity by default and changed with the set HCOR command */
                dense.xIonDense[ipHYDROGEN][0]*1.7e-4 * dense.HCorrFac;
        dense.EdenHCorr_f = (realnum)dense.EdenHCorr;
        
        /*>>chng 93 jun 04,
         * term with hi added June 4, 93, to account for warm pdr */
        /* >>chng 05 jan 05, Will Henney noticed that 1.e-4 used here is not same as
         * 1.7e-4 used for EdenHCorr, which had rewritten the expression.
         * change so that edensqte uses EdenHCorr rather than reevaluating */
        /*dense.edensqte = ((dense.eden + dense.xIonDense[ipHYDROGEN][0]/1e4)/phycon.sqrte);*/
        dense.edensqte = dense.EdenHCorr/phycon.sqrte;
        dense.cdsqte = dense.edensqte*COLL_CONST;
        dense.SqrtEden = sqrt(dense.eden);

        /* rest have to do with radiation field and frequency mesh which may not be defined yet */
        if( !lgRfieldMalloced || !rfield.lgMeshSetUp() )
                return;

        /* correction factors for induced recombination, 
         * also used as Boltzmann factors
         * check for zero is because ContBoltz is zeroed out in initialization
         * of code, its possible this is a constant density grid of models
         * in which the code is called as a subroutine */
        /* >>chng 01 aug 21, must also test on size of continuum nflux because 
         * conintitemp can increase nflux then call this routine, although 
         * temp may not have changed */
        if( ! fp_equal(tgffused, phycon.te) || rfield.ContBoltz[0] <= 0. )
        {
                tgffused = phycon.te;
                for( long i=0; i < rfield.nflux_with_check; ++i )
                        rfield.vexp_arg[i] = -rfield.anu(i)/phycon.te_ryd;
                /* atom_level2 uses ContBoltz to see whether the rates will be significant.
                 * If the numbers did not agree then this test would be flawed, resulting in
                 * div by zero */
                vexp( rfield.vexp_arg, rfield.ContBoltz, 0, rfield.nflux_with_check );
                for( long i=0; i < rfield.nflux_with_check; ++i )
                        rfield.vexp_arg[i] = -rfield.anumin(i)/phycon.te_ryd;
                /* this is Boltzmann factor averaged over the width of the cell */
                vexp( rfield.vexp_arg, rfield.ContBoltzAvg, 0, rfield.nflux_with_check );
                for( long i=0; i < rfield.nflux_with_check; ++i )
                        rfield.vexp_arg[i] = -rfield.widflx(i)/phycon.te_ryd;
                vexpm1( rfield.vexp_arg, rfield.ContBoltzHelp1, 0, rfield.nflux_with_check );
                for( long i=0; i < rfield.nflux_with_check; ++i )
                {
                        rfield.ContBoltzHelp1[i] /= rfield.vexp_arg[i];
                        rfield.ContBoltzAvg[i] *= rfield.ContBoltzHelp1[i];
                }
                vexp( rfield.vexp_arg, rfield.ContBoltzHelp2, 0, rfield.nflux_with_check );
                /* ipMaxBolt is number of non-zero cells, so non-zero up through ipMaxBolt-1 */
                rfield.ipMaxBolt = rfield.nflux_with_check;
                for( long i=rfield.nflux_with_check-1; i >= 0; --i )
                {
                        if( rfield.ContBoltz[i] > 0. )
                                break;
                        rfield.ipMaxBolt = i;
                }
        }

        /* find frequency where thin to bremsstrahlung or plasma frequency */
        tauff();
}

/*tauff compute optical depth where cloud is thin to free-free and plasma freq */
STATIC void tauff()
{
        realnum fac;

        /* simply return if space not yet allocated */
        if( !lgOpacMalloced )
                return;

        DEBUG_ENTRY( "tauff()" );

        if( !conv.nTotalIoniz )
                rfield.ipEnergyBremsThin = 0;

        /* routine sets variable ipEnergyBremsThin, index for lowest cont cell that is optically thin */
        /* find frequency where continuum thin to free-free */
        while( rfield.ipEnergyBremsThin < rfield.nflux && 
                opac.TauAbsGeo[0][rfield.ipEnergyBremsThin] >= 1. )
        {
                ++rfield.ipEnergyBremsThin;
        }

        /* TFF will be frequency where cloud becomes optically thin to bremsstrahlung
         * >>chng 96 may 7, had been 2, change as per Kevin Volk bug report */
        if( rfield.ipEnergyBremsThin > 1 && opac.TauAbsGeo[0][rfield.ipEnergyBremsThin] > 0.001 )
        {
                /* tau can be zero when plasma frequency is within energy grid, */
                fac = (1.f - opac.TauAbsGeo[0][rfield.ipEnergyBremsThin-1])/(opac.TauAbsGeo[0][rfield.ipEnergyBremsThin] - 
                  opac.TauAbsGeo[0][rfield.ipEnergyBremsThin-1]);
                fac = MAX2(fac,0.f);
                rfield.EnergyBremsThin = rfield.anu(rfield.ipEnergyBremsThin-1) + rfield.widflx(rfield.ipEnergyBremsThin-1)*fac;
        }
        else
        {
                rfield.EnergyBremsThin = 0.f;
        }

        /* did not include plasma freq before
         * function returns larger of these two frequencies */
        rfield.EnergyBremsThin = MAX2(rfield.plsfrq,rfield.EnergyBremsThin);

        /* now increment ipEnergyBremsThin still further, until above plasma frequency */
        while( rfield.ipEnergyBremsThin < rfield.nflux && 
                rfield.anu(rfield.ipEnergyBremsThin) <= rfield.EnergyBremsThin )
        {
                ++rfield.ipEnergyBremsThin;
        }
        return;
}

realnum GetDopplerWidth( realnum massAMU )
{
        ASSERT( massAMU > 0. );
        // force a fairly conservative upper limit
        ASSERT( massAMU < 10000. );

        /* usually TurbVel =0, reset with turbulence command
         * cm/s here, but was entered in km/s with command */
        double turb2 = POW2(DoppVel.TurbVel);

        /* this is option to dissipate the turbulence.  DispScale is entered with
         * dissipate keyword on turbulence command.  The velocity is reduced here,
         * by an assumed exponential scale, and also adds heat */
        if( DoppVel.DispScale > 0. )
        {
                /* square of exp depth dependence */
                turb2 *= sexp( 2.*radius.depth / DoppVel.DispScale );
        }

        /* in case of D-Critical flow include initial velocity as
         * a component of turbulence */
        if( ! ( wind.lgBallistic() || wind.lgStatic() ) )
        {
                turb2 += POW2(wind.windv0);
        }

        realnum width = (realnum)sqrt(2.*BOLTZMANN/ATOMIC_MASS_UNIT*phycon.te/massAMU+turb2);
        ASSERT( width > 0.f );
        return width;
}

realnum GetAveVelocity( realnum massAMU )
{
#if 0
        /* usually TurbVel =0, reset with turbulence command
         * cm/s here, but was entered in km/s with command */
        double turb2 = POW2(DoppVel.TurbVel);

        /* this is option to dissipate the turbulence.  DispScale is entered with
         * dissipate keyword on turbulence command.  The velocity is reduced here,
         * by an assumed exponential scale, and also adds heat */
        if( DoppVel.DispScale > 0. )
        {
                /* square of exp depth dependence */
                turb2 *= sexp( 2.*radius.depth / DoppVel.DispScale );
        }

        /* in case of D-Critical flow include initial velocity as
         * a component of turbulence */
        if( ! ( wind.lgBallistic() || wind.lgStatic() ) )
        {
                turb2 += POW2(wind.windv0);
        }
#endif
        DEBUG_ENTRY( "GetAveVelocity()" );

        /* this is average (NOT rms) particle speed for Maxwell distribution, Mihalas 70, 9-70 */
        fixit("turbulence was included here for molecules but not ions.  Now neither. Resolve.");
        return (realnum)sqrt(8.*BOLTZMANN/PI/ATOMIC_MASS_UNIT*phycon.te/massAMU);
}