trunk/models/vessel.a4c

(*	ASCEND modelling environment
	Copyright (C) 1998, 2007 Carnegie Mellon University

	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, 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, see <http://www.gnu.org/licenses/>.
*)
REQUIRE "atoms.a4l"; (* => atoms.a4l, measures.a4l, system.a4l, basemodel.a4l *)
(*
	by Arthur W Westerberg, Benjamin A Allan and John Pye

	This file contains two model declarations. The first is a 'full-blown'
	vessel model build by extending the declaration from vesselPlain.a4c. This
	new model contains a number of initialisation routines that ensure that
	the model can easily be put into a solvable state. The model also contains
	a 'values' method that defines the base case for which we are solving.

	The second model in this file is an optimisation problem. Here, we are 
	REFINING the earlier 'vessel' model with the addition of an objective
	function (see the 'OPTIMIZE' statement). We can then load the model and
	optimise it.
*)

MODEL vessel;

	(* variables *)
	side_area, end_area	 IS_A area;
	vessel_vol, wall_vol IS_A volume;
	wall_thickness, H, D IS_A distance;
	H_to_D_ratio         IS_A factor;
	metal_density        IS_A mass_density;
	metal_mass           IS_A mass;

	(* equations *)
	FlatEnds:      end_area = 1{PI} * D^2 / 4;
	Sides:         side_area = 1{PI} * D * H;
	Cylinder:      vessel_vol = end_area * H;
	Metal_volume:  (side_area + 2 * end_area) * wall_thickness = wall_vol;
	HD_definition: D * H_to_D_ratio = H;
	VesselMass:    metal_mass = metal_density * wall_vol;

METHODS
    METHOD default;
		H_to_D_ratio :=	2;
    END default;

    METHOD specify;
		FIX vessel_vol;
		FIX H_to_D_ratio;
		FIX wall_thickness;
		FIX metal_density;
    END specify;

    METHOD values;
		vessel_vol      := 250 {ft^3};
		wall_thickness  := 5 {mm};
		metal_density   := 13000 {kg/m^3};
    END values;

	METHOD on_load;
		RUN default_self;
		RUN reset;
		RUN values;
	END on_load;
END vessel;


MODEL vessel_optimize REFINES vessel;

	cost  IS_A monetary_unit;
	a     IS_A cost_per_volume;

    obj1def: cost = a * wall_thickness * (side_area + 2*(4/1{PI})*end_area);

    obj1: MINIMIZE cost;

METHODS
    METHOD specify;
		FIX vessel_vol;
		FIX wall_thickness;
		FIX metal_density;
		FIX a;
    END specify;

    METHOD values;
		vessel_vol      :=  250 {ft^3};
		wall_thickness  :=  5 {mm};
		metal_density   :=  13000 {kg/m^3};

		(* a is the cost per cubic foot of metal. rather arbitrary. *)
		a               :=  10 {USD/m^3};
    END values;

	METHOD on_load;
		RUN default_self;
		RUN reset;
		RUN values;
	END on_load;
END vessel_optimize;

1	johnpye	1294	(* ASCEND modelling environment
2			Copyright (C) 1998, 2007 Carnegie Mellon University
3
4			This program is free software; you can redistribute it and/or modify
5			it under the terms of the GNU General Public License as published by
6			the Free Software Foundation; either version 2, or (at your option)
7			any later version.
8
9			This program is distributed in the hope that it will be useful,
10			but WITHOUT ANY WARRANTY; without even the implied warranty of
11			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12			GNU General Public License for more details.
13
14			You should have received a copy of the GNU General Public License
15	jpye	2649	along with this program. If not, see <http://www.gnu.org/licenses/>.
16	johnpye	1294	*)
17			REQUIRE "atoms.a4l"; (* => atoms.a4l, measures.a4l, system.a4l, basemodel.a4l *)
18	aw0a	1	(*
19	johnpye	1294	by Arthur W Westerberg, Benjamin A Allan and John Pye
20	aw0a	1
21	johnpye	1294	This file contains two model declarations. The first is a 'full-blown'
22			vessel model build by extending the declaration from vesselPlain.a4c. This
23			new model contains a number of initialisation routines that ensure that
24			the model can easily be put into a solvable state. The model also contains
25			a 'values' method that defines the base case for which we are solving.
26
27			The second model in this file is an optimisation problem. Here, we are
28			REFINING the earlier 'vessel' model with the addition of an objective
29			function (see the 'OPTIMIZE' statement). We can then load the model and
30			optimise it.
31			*)
32
33	aw0a	1	MODEL vessel;
34
35			(* variables *)
36	johnpye	1294	side_area, end_area IS_A area;
37			vessel_vol, wall_vol IS_A volume;
38			wall_thickness, H, D IS_A distance;
39			H_to_D_ratio IS_A factor;
40			metal_density IS_A mass_density;
41			metal_mass IS_A mass;
42	aw0a	1
43			(* equations *)
44	johnpye	1294	FlatEnds: end_area = 1{PI} * D^2 / 4;
45			Sides: side_area = 1{PI} * D * H;
46			Cylinder: vessel_vol = end_area * H;
47			Metal_volume: (side_area + 2 * end_area) * wall_thickness = wall_vol;
48			HD_definition: D * H_to_D_ratio = H;
49			VesselMass: metal_mass = metal_density * wall_vol;
50	aw0a	1
51			METHODS
52	johnpye	1294	METHOD default;
53			H_to_D_ratio := 2;
54			END default;
55	aw0a	1
56			METHOD specify;
57	johnpye	1294	FIX vessel_vol;
58			FIX H_to_D_ratio;
59			FIX wall_thickness;
60			FIX metal_density;
61	aw0a	1	END specify;
62
63			METHOD values;
64	johnpye	1294	vessel_vol := 250 {ft^3};
65			wall_thickness := 5 {mm};
66			metal_density := 13000 {kg/m^3};
67	aw0a	1	END values;
68
69	johnpye	1294	METHOD on_load;
70			RUN default_self;
71			RUN reset;
72			RUN values;
73			END on_load;
74	aw0a	1	END vessel;
75
76	jpye	1621
77	aw0a	1	MODEL vessel_optimize REFINES vessel;
78
79	johnpye	1294	cost IS_A monetary_unit;
80			a IS_A cost_per_volume;
81	aw0a	1
82			obj1def: cost = a * wall_thickness * (side_area + 2(4/1{PI})end_area);
83
84	johnpye	1294	obj1: MINIMIZE cost;
85	aw0a	1
86	johnpye	1294	METHODS
87	aw0a	1	METHOD specify;
88	johnpye	1294	FIX vessel_vol;
89			FIX wall_thickness;
90			FIX metal_density;
91			FIX a;
92	aw0a	1	END specify;
93
94			METHOD values;
95	johnpye	1294	vessel_vol := 250 {ft^3};
96			wall_thickness := 5 {mm};
97			metal_density := 13000 {kg/m^3};
98	aw0a	1
99	johnpye	1294	(* a is the cost per cubic foot of metal. rather arbitrary. *)
100			a := 10 {USD/m^3};
101	aw0a	1	END values;
102
103	johnpye	1294	METHOD on_load;
104			RUN default_self;
105			RUN reset;
106			RUN values;
107			END on_load;
108	jpye	1621	END vessel_optimize;
109	johnpye	1294