dynamic_viscosity.f90 1.71 KB
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!**********************************************************************
! Copyright 1998,1999,2000,2001,2002,2005,2007,2008,2009,2010         *
! Andreas Stohl, Petra Seibert, A. Frank, Gerhard Wotawa,             *
! Caroline Forster, Sabine Eckhardt, John Burkhart, Harald Sodemann   *
!                                                                     *
! This file is part of FLEXPART.                                      *
!                                                                     *
! FLEXPART is free software: you can redistribute it and/or modify    *
! it under the terms of the GNU General Public License as published by*
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!                                                                     *
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Matthias Langer's avatar
 
Matthias Langer committed
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! Function calculates dynamic viscosity of air (kg/m/s) as function of
! temperature (K) using Sutherland's formula

real function viscosity(t)

  implicit none

  real :: t
  real,parameter :: c=120.,t_0=291.15,eta_0=1.827e-5

  viscosity=eta_0*(t_0+c)/(t+c)*(t/t_0)**1.5

  return

end function viscosity