From f67cfb1c920440b26c45bff757f25fb9b11fcf20 Mon Sep 17 00:00:00 2001 From: Emmanuel Branlard Date: Wed, 31 Aug 2022 11:10:50 +0200 Subject: [PATCH] AA: fix BL-thickness for heavily-tripped airfoil, and adding equation references (see #1079) --- modules/aerodyn/src/AeroAcoustics.f90 | 38 ++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 6 deletions(-) diff --git a/modules/aerodyn/src/AeroAcoustics.f90 b/modules/aerodyn/src/AeroAcoustics.f90 index e463a8e34e..5670ee6670 100644 --- a/modules/aerodyn/src/AeroAcoustics.f90 +++ b/modules/aerodyn/src/AeroAcoustics.f90 @@ -1,6 +1,27 @@ !********************************************************************************************************************************** -! File last committed: 2020-02-12 +! LICENSING +! Copyright (C) 2015-2016 National Renewable Energy Laboratory +! Copyright (C) 2016-2017 Envision Energy USA, LTD +! +! This file is part of AeroDyn. +! +! Licensed under the Apache License, Version 2.0 (the "License"); +! you may not use this file except in compliance with the License. +! You may obtain a copy of the License at +! +! http://www.apache.org/licenses/LICENSE-2.0 +! +! Unless required by applicable law or agreed to in writing, software +! distributed under the License is distributed on an "AS IS" BASIS, +! WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +! See the License for the specific language governing permissions and +! limitations under the License. +! !********************************************************************************************************************************** +! +! References: +! [1] Brooks, T. F.; Pope, D. S. & Marcolini, M. A., Airfoil self-noise and prediction, +! NASA, NASA, 1989. https://ntrs.nasa.gov/search.jsp?R=19890016302 module AeroAcoustics use NWTC_Library @@ -2147,31 +2168,36 @@ SUBROUTINE THICK(C,M,RC,ALPSTAR,p,DELTAP,DSTRS,DSTRP,StallVal,errStat,errMsg) real(ReKi) :: DSTR0 ! DISPLACEMENT THICKNESS AT ZERO ANGLE OF ATTACK METERS ErrStat = ErrID_None ErrMsg = "" - ! - DELTA0 = 10.**(1.6569-.9045*LOG10(RC)+.0596*LOG10(RC)**2.)*C - IF (p%ITRIP .GT. 0) DELTA0 = 10.**(1.892-0.9045*LOG(RC)+0.0596*LOG(RC)**2.)*C + ! Boundary layer thickness + DELTA0 = 10.**(1.6569-0.9045*LOG10(RC)+0.0596*LOG10(RC)**2.)*C ! (untripped) Eq. (5) of [1] + IF (p%ITRIP .GT. 0) DELTA0 = 10.**(1.892 -0.9045*LOG10(RC)+0.0596*LOG10(RC)**2.)*C ! (heavily tripped) Eq. (2) of [1] IF (p%ITRIP .EQ. 2) DELTA0=.6*DELTA0 - ! Pressure side boundary layer thickness + ! Pressure side boundary layer thickness, Eq (8) of [1] DELTAP = 10.**(-.04175*ALPSTAR+.00106*ALPSTAR**2.)*DELTA0 ! Compute zero angle of attack displacement thickness IF ((p%ITRIP .EQ. 1) .OR. (p%ITRIP .EQ. 2)) THEN + ! Heavily tripped, Eq. (3) of [1] IF (RC .LE. .3E+06) DSTR0 = .0601 * RC **(-.114)*C IF (RC .GT. .3E+06) & DSTR0=10.**(3.411-1.5397*LOG10(RC)+.1059*LOG10(RC)**2.)*C + ! Lightly tripped IF (p%ITRIP .EQ. 2) DSTR0 = DSTR0 * .6 ELSE + ! Untripped, Eq. (6) of [1] DSTR0=10.**(3.0187-1.5397*LOG10(RC)+.1059*LOG10(RC)**2.)*C ENDIF - ! Pressure side displacement thickness + ! Pressure side displacement thickness, Eq. (9) of [1] DSTRP = 10.**(-.0432*ALPSTAR+.00113*ALPSTAR**2.)*DSTR0 ! IF (p%ITRIP .EQ. 3) DSTRP = DSTRP * 1.48 ! commented since itrip is never 3 check if meant 2.(EB_DTU) ! Suction side displacement thickness IF (p%ITRIP .EQ. 1) THEN + ! Heavily tripped, Eq. (12) of [1] IF (ALPSTAR .LE. 5.) DSTRS=10.**(.0679*ALPSTAR)*DSTR0 IF((ALPSTAR .GT. 5.).AND.(ALPSTAR .LE. StallVal)) & DSTRS = .381*10.**(.1516*ALPSTAR)*DSTR0 IF (ALPSTAR .GT. StallVal)DSTRS=14.296*10.**(.0258*ALPSTAR)*DSTR0 ELSE + ! Untripped or lightly tripped, Eq. (15) of [1] IF (ALPSTAR .LE. 7.5)DSTRS =10.**(.0679*ALPSTAR)*DSTR0 IF((ALPSTAR .GT. 7.5).AND.(ALPSTAR .LE. StallVal)) & DSTRS = .0162*10.**(.3066*ALPSTAR)*DSTR0