1! 2! CalculiX - A 3-dimensional finite element program 3! Copyright (C) 1998-2021 Guido Dhondt 4! 5! This program is free software; you can redistribute it and/or 6! modify it under the terms of the GNU General Public License as 7! published by the Free Software Foundation(version 2); 8! 9! 10! This program is distributed in the hope that it will be useful, 11! but WITHOUT ANY WARRANTY; without even the implied warranty of 12! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13! GNU General Public License for more details. 14! 15! You should have received a copy of the GNU General Public License 16! along with this program; if not, write to the Free Software 17! Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18! 19! This subroutines enables to calculate the reynolds number correction after: 20! "Discharge coeffcients for incompressible non-cavitating flowthrough long orifices" 21! A. Lichtarowicz, R.K duggins and E. Markland 22! Journal Mechanical Engineering Science , vol 7, No. 2, 1965 23! 24! author: Yannick Muller 25! 26 subroutine cd_lichtarowicz(cd,cdu,reynolds,amod,bdh) 27! 28 implicit none 29! 30 real*8 cdu,reynolds,amod,bdh,eps,A1,cd_diff,cd0,cd 31! 32 cd0=cdu 33 cd_diff=1.d0 34! 35 do 36! 37 if(cd_diff.lt.1.d-3) exit 38! 39 cd=cd0 40 A1=20/(reynolds*dsqrt(1.d0-Amod**2))*(1.d0+2.25d0*bdh) 41 eps=(0.005d0*bdh)/(1.d0+7.5d0*(log10(0.00015d0*reynolds* 42 & dsqrt(1.d0-Amod**2)/cd))**2) 43 44 cd=((-1/cdu+eps)+dsqrt((1/cdu-eps)**2.d0+4.d0*A1))/(2*A1) 45! 46 cd_diff=dabs(cd-cd0) 47! 48 cd0=cd 49! 50 enddo 51! 52 return 53 end 54