[92fab65] | 1 | ! SPDX-FileCopyrightText: FLEXPART 1998-2019, see flexpart_license.txt |
---|
| 2 | ! SPDX-License-Identifier: GPL-3.0-or-later |
---|
[332fbbd] | 3 | |
---|
[e200b7a] | 4 | subroutine windalign(u,v,ffap,ffcp,ux,vy) |
---|
| 5 | ! i i i i o o |
---|
| 6 | !***************************************************************************** |
---|
| 7 | ! * |
---|
| 8 | ! Transformation from along- and cross-wind components to u and v * |
---|
| 9 | ! components. * |
---|
| 10 | ! * |
---|
| 11 | ! Author: A. Stohl * |
---|
| 12 | ! * |
---|
| 13 | ! 3 June 1996 * |
---|
| 14 | ! * |
---|
| 15 | !***************************************************************************** |
---|
| 16 | ! * |
---|
| 17 | ! Variables: * |
---|
| 18 | ! ffap turbulent wind in along wind direction * |
---|
| 19 | ! ffcp turbulent wind in cross wind direction * |
---|
| 20 | ! u main wind component in x direction * |
---|
| 21 | ! ux turbulent wind in x direction * |
---|
| 22 | ! v main wind component in y direction * |
---|
| 23 | ! vy turbulent wind in y direction * |
---|
| 24 | ! * |
---|
| 25 | !***************************************************************************** |
---|
| 26 | |
---|
| 27 | implicit none |
---|
| 28 | |
---|
| 29 | real :: u,v,ffap,ffcp,ux,vy,ffinv,ux1,ux2,vy1,vy2,sinphi,cosphi |
---|
| 30 | real,parameter :: eps=1.e-30 |
---|
| 31 | |
---|
| 32 | |
---|
| 33 | ! Transform along wind components |
---|
| 34 | !******************************** |
---|
| 35 | |
---|
| 36 | ffinv=1./max(sqrt(u*u+v*v),eps) |
---|
| 37 | sinphi=v*ffinv |
---|
| 38 | vy1=sinphi*ffap |
---|
| 39 | cosphi=u*ffinv |
---|
| 40 | ux1=cosphi*ffap |
---|
| 41 | |
---|
| 42 | |
---|
| 43 | ! Transform cross wind components |
---|
| 44 | !******************************** |
---|
| 45 | |
---|
| 46 | ux2=-sinphi*ffcp |
---|
| 47 | vy2=cosphi*ffcp |
---|
| 48 | |
---|
| 49 | |
---|
| 50 | ! Add contributions from along and cross wind components |
---|
| 51 | !******************************************************* |
---|
| 52 | |
---|
| 53 | ux=ux1+ux2 |
---|
| 54 | vy=vy1+vy2 |
---|
| 55 | |
---|
| 56 | end subroutine windalign |
---|