1!----------------------------------------------------------------------
2      SUBROUTINE WAKE_DRDX(X,DRDX)
3!----------------------------------------------------------------------
4!
5! --- PRIME      Version:  1.0     Level:  970812             WAKE_DRDX
6!                J. Scire, D. Strimaitis,  EARTH TECH
7!                Prepared for EPRI under contract WO3527-01
8!
9! --- PURPOSE:  Compute the plume radius growth rate in the wake
10!               by interpolating among the stored values.
11!
12! --- INPUTS:
13!                X - real       - Downwind distance (m) from source
14!
15!     Common block /PARAMS/ variables:
16!           MXNTR
17!     Common block /WAKEDAT/ variables:
18!           NWAK, XWAK(mxntr), DRWAK(mxntr)
19!
20! --- OUTPUT:
21!             DRDX - real       - Rate of growth of plume radius at
22!                                 downwind distance X from source
23!
24! --- WAKE_DRDX called by:  NUMRISE
25! --- WAKE_DRDX calls:      none
26!----------------------------------------------------------------------
27!
28      INCLUDE 'params.pri'
29      INCLUDE 'wakedat.pri'
30!
31! --- Set growth rate to zero outside interpolation region
32! --- (all x outside wake)
33      IF ( X.GT.XWAK(NWAK) .OR. X.LT.XWAK(1) ) THEN                     !2202976
34         DRDX = 0.0                                                     ! 844044
35      ELSEIF ( NWAK.LE.1 ) THEN
36! ---    Wake turbulence does not alter this plume
37         DRDX = 0.0                                                     !     88
38      ELSE
39         NWKM1 = NWAK - 1                                               !1358844
40         DRDX = DRWAK(1)
41         DO I = NWKM1 , 1 , -1
42            IF ( X.GE.XWAK(I) ) THEN                                    ! 28645K
43               IP1 = I + 1                                              !1358844
44               DRDX = DRWAK(IP1) - (DRWAK(IP1)-DRWAK(I))*(XWAK(IP1)-X)  &
45     &                /(XWAK(IP1)-XWAK(I))
46               RETURN
47            ENDIF
48         ENDDO
49      ENDIF
50
51      CONTINUE                                                          ! 844132
52      END


HyperKWIC - Version 1.00DD executed at 20:00 on 1 Mar 2018 | Personal or Academic or Evaluation User | Free for Non-Commercial, Non-Government Use