models/steam/thermalequilibrium3.a4c

REQUIRE "ivpsystem.a4l";
REQUIRE "johnpye/thermo_types.a4c";
REQUIRE "johnpye/steam/iapwssat.a4c";

IMPORT "johnpye/extpy/extpy";
IMPORT "johnpye/listnotes";
IMPORT "johnpye/solve";

(* 
	Simplified version of models/johnpye/thermalequilibrium2.a4c. This one uses
	saturated steam properties only (and is not suitable for cases where
	properties pass outside those limits).

	NOTE: set the starting step to 0.1 and the minimum step to 0.01 s, and
	integrate from 0 to 3000 s.
*)
ADD NOTES IN thermalequilibrium3;
	'solver' name {QRSlv}
	'QRSlv' iterationlimit {50}
	'QRSlv' singtol {1e-10}
	(* following are not implemented yet *)
	'LSODE' minstep {0.01} 
	'LSODE' firststep {0.1}
	'LSODE' duration {3000}
END NOTES;

MODEL thermalequilibrium3;
	S[1..2] IS_A iapwssat;
	m[1..2] IS_A mass;
	h IS_A heat_transfer_coefficient;
	A IS_A area;

	p ALIASES S[1].p;
	S[2].p = S[1].p;

	Q IS_A energy_rate;
	Q = h*A*(S[1].T - S[2].T); (* rate of heat transfer from 1 to 2 *)
	m[1]*dhdt[1] = -Q;
	m[2]*dhdt[2] = +Q;
	
	dhdt[1..2] IS_A delta_specific_power;

	t IS_A time;
METHODS
METHOD specify;
	FIX	h, A, m[1..2], S[1..2].h, p;
END specify;	
METHOD values;
	A := 1 {m^2};
	h := 10 {W/m^2/K};

	p := 1 {bar};

	m[1] := 2 {kg};
	S[1].h := 1000 {kJ/kg};
	m[2] := 10 {kg};
	S[2].h := 2000 {kJ/kg};
END values;
METHOD ode_init;
	FOR i IN [1..2] DO
		S[i].h.ode_id := i;
		dhdt[i].ode_id := i;
		S[i].h.ode_type := 1;
		dhdt[i].ode_type := 2;
	END FOR;

	Q.obs_id := 2;
	S[1].h.obs_id := 3;
	S[2].h.obs_id := 4;

	t.ode_type := -1;
	t := 0 {s};
END ode_init;
METHOD on_load;
	RUN reset;
	RUN values;
	EXTERNAL setup_solver(SELF);
	EXTERNAL solve(SELF);
	RUN ode_init;
END on_load;

END thermalequilibrium3;

1	johnpye	1042	REQUIRE "ivpsystem.a4l";
2			REQUIRE "johnpye/thermo_types.a4c";
3			REQUIRE "johnpye/steam/iapwssat.a4c";
4
5			IMPORT "johnpye/extpy/extpy";
6			IMPORT "johnpye/listnotes";
7			IMPORT "johnpye/solve";
8
9			(*
10	johnpye	1043	Simplified version of models/johnpye/thermalequilibrium2.a4c. This one uses
11			saturated steam properties only (and is not suitable for cases where
12			properties pass outside those limits).
13	johnpye	1042
14			NOTE: set the starting step to 0.1 and the minimum step to 0.01 s, and
15			integrate from 0 to 3000 s.
16			*)
17			ADD NOTES IN thermalequilibrium3;
18			'solver' name {QRSlv}
19			'QRSlv' iterationlimit {50}
20			'QRSlv' singtol {1e-10}
21			(* following are not implemented yet *)
22			'LSODE' minstep {0.01}
23			'LSODE' firststep {0.1}
24			'LSODE' duration {3000}
25			END NOTES;
26
27			MODEL thermalequilibrium3;
28			S[1..2] IS_A iapwssat;
29			m[1..2] IS_A mass;
30			h IS_A heat_transfer_coefficient;
31			A IS_A area;
32
33			p ALIASES S[1].p;
34			S[2].p = S[1].p;
35
36			Q IS_A energy_rate;
37			Q = hA(S[1].T - S[2].T); (* rate of heat transfer from 1 to 2 *)
38			m[1]*dhdt[1] = -Q;
39			m[2]*dhdt[2] = +Q;
40
41			dhdt[1..2] IS_A delta_specific_power;
42
43			t IS_A time;
44			METHODS
45			METHOD specify;
46			FIX h, A, m[1..2], S[1..2].h, p;
47			END specify;
48			METHOD values;
49			A := 1 {m^2};
50			h := 10 {W/m^2/K};
51
52			p := 1 {bar};
53
54			m[1] := 2 {kg};
55			S[1].h := 1000 {kJ/kg};
56			m[2] := 10 {kg};
57			S[2].h := 2000 {kJ/kg};
58			END values;
59			METHOD ode_init;
60			FOR i IN [1..2] DO
61			S[i].h.ode_id := i;
62			dhdt[i].ode_id := i;
63			S[i].h.ode_type := 1;
64			dhdt[i].ode_type := 2;
65			END FOR;
66
67			Q.obs_id := 2;
68			S[1].h.obs_id := 3;
69			S[2].h.obs_id := 4;
70
71			t.ode_type := -1;
72			t := 0 {s};
73			END ode_init;
74			METHOD on_load;
75			RUN reset;
76			RUN values;
77			EXTERNAL setup_solver(SELF);
78			EXTERNAL solve(SELF);
79			RUN ode_init;
80			END on_load;
81
82			END thermalequilibrium3;
83