models/johnpye/thermalequilibrium.a4c

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

(* 
	this model aims to show the evolution of thermal equilibrium between
	two containers of water/steam with a simple convection coefficient
	relation at the interface

	This simple model works without any realistic fluid properties. It's basically
	just demonstrating Newton's Law of Cooling.

	This model was used as a test case for the Integrator functionality in the
	PyGTK GUI.
*)
MODEL thermalequilibrium;
	T_1 IS_A temperature;
	T_2 IS_A temperature;
	m_1, m_2 IS_A mass;
	C_p IS_A specific_heat_capacity;
	h IS_A heat_transfer_coefficient;
	A IS_A area;

	Q IS_A energy_rate;
	Q = h*A*(T_1 - T_2); (* rate of heat transfer from 1 to 2 *)
	m_1*C_p*dT1dt = -Q;
	m_2*C_p*dT2dt = +Q;
	
	dT1dt IS_A temperature_rate;
	dT2dt IS_A temperature_rate;

	t IS_A time;
METHODS
METHOD on_load;
	FIX C_p, h, A, m_1, m_2, T_1, T_2;
	A := 1 {m^2};
	h := 10 {W/m^2/K};
	C_p := 4.2 {kJ/kg/K};
	m_1 := 10 {kg};
	m_2 := 10 {kg};

	T_1 := 500 {K};
	T_2 := 290 {K};

	t.ode_type := -1;

	T_1.ode_id := 1;
	dT1dt.ode_id := 1;
	T_1.ode_type := 1;
	dT1dt.ode_type := 2;

	T_2.ode_id := 2;
	dT2dt.ode_id := 2;
	T_2.ode_type := 1;
	dT2dt.ode_type := 2;

	Q.obs_id := 2;
	T_1.obs_id := 3;
	T_2.obs_id := 4;
	
END on_load;

END thermalequilibrium;
1	REQUIRE "ivpsystem.a4l";
2	REQUIRE "johnpye/thermo_types.a4c";
3
4	(*
5	this model aims to show the evolution of thermal equilibrium between
6	two containers of water/steam with a simple convection coefficient
7	relation at the interface
8
9	This simple model works without any realistic fluid properties. It's basically
10	just demonstrating Newton's Law of Cooling.
11
12	This model was used as a test case for the Integrator functionality in the
13	PyGTK GUI.
14	*)
15	MODEL thermalequilibrium;
16	T_1 IS_A temperature;
17	T_2 IS_A temperature;
18	m_1, m_2 IS_A mass;
19	C_p IS_A specific_heat_capacity;
20	h IS_A heat_transfer_coefficient;
21	A IS_A area;
22
23	Q IS_A energy_rate;
24	Q = hA(T_1 - T_2); (* rate of heat transfer from 1 to 2 *)
25	m_1C_pdT1dt = -Q;
26	m_2C_pdT2dt = +Q;
27
28	dT1dt IS_A temperature_rate;
29	dT2dt IS_A temperature_rate;
30
31	t IS_A time;
32	METHODS
33	METHOD on_load;
34	FIX C_p, h, A, m_1, m_2, T_1, T_2;
35	A := 1 {m^2};
36	h := 10 {W/m^2/K};
37	C_p := 4.2 {kJ/kg/K};
38	m_1 := 10 {kg};
39	m_2 := 10 {kg};
40
41	T_1 := 500 {K};
42	T_2 := 290 {K};
43
44	t.ode_type := -1;
45
46	T_1.ode_id := 1;
47	dT1dt.ode_id := 1;
48	T_1.ode_type := 1;
49	dT1dt.ode_type := 2;
50
51	T_2.ode_id := 2;
52	dT2dt.ode_id := 2;
53	T_2.ode_type := 1;
54	dT2dt.ode_type := 2;
55
56	Q.obs_id := 2;
57	T_1.obs_id := 3;
58	T_2.obs_id := 4;
59
60	END on_load;
61
62	END thermalequilibrium;