Initial commit from Polytechnique Montreal

1 files changed, 61 insertions, 0 deletions

diff --git a/Utilib/src/backwards_impl.h b/Utilib/src/backwards_impl.h
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+++ b/Utilib/src/backwards_impl.h
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+/*
+freesteam - IAPWS-IF97 steam tables library
+Copyright (C) 2004-2009  John Pye
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+*//** @file
+	Implementation details for backwards equations. Intended that
+	this header file would only be used for internal tests etc.
+*/
+#ifndef FREESTEAM_BACKWARDS_IMPL_H
+#define FREESTEAM_BACKWARDS_IMPL_H
+
+#include "common.h"
+
+#define SQ(X) ((X)*(X))
+#define CUBE(X) ((X)*(X)*(X))
+
+/* boundary between subregions 3a and 3b in region 3 for (p,h) */
+
+#define REGION3_B3AB_PSTAR (1.e6)
+#define REGION3_B3AB_HSTAR (1.e3)
+#define REGION3_B3AB_ETA(H) ((H)/REGION3_B3AB_HSTAR)
+#define REGION3_B3AB_PI(P) ((P)/REGION3_B3AB_PSTAR)
+
+#define REGION3_B3AB_PH(P,H) (REGION3_B3AB_ETA(H) - (\
+	2014.64004206875 \
+	+ 3.74696550136983*REGION3_B3AB_PI(P) \
+	- 2.19921901054187E-02 * SQ(REGION3_B3AB_PI(P)) \
+	+ 8.7513168600995E-05 * CUBE(REGION3_B3AB_PI(P)) \
+	))
+
+
+/* boundary between subregions 2 and 3 in region 2 for (p,h) */
+
+#define REGION2_B2BC_PSTAR (1.e6)
+#define REGION2_B2BC_HSTAR (1.e3)
+#define REGION2_B2BC_ETA(H) ((H)/REGION2_B2BC_HSTAR)
+#define REGION2_B2BC_PI(P) ((P)/REGION2_B2BC_PSTAR)
+
+#define REGION2_B2BC_PH(P,H) (\
+	(REGION2_B2BC_PI(P) - (\
+	905.84278514723 \
+	- 0.67955786399241*REGION2_B2BC_ETA(H) \
+	+ 1.2809002730136E-04 * SQ(REGION2_B2BC_ETA(H)) \
+	)))
+
+#endif
+
+