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Contents of /trunk/models/johnpye/fprops/heatex_pinch.a4c

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Revision 2674 - (show annotations) (download) (as text)
Thu Jan 24 02:27:41 2013 UTC (9 years, 5 months ago) by jpye
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Brayton cycle models working OK know with new FPROPS.
1 REQUIRE "johnpye/fprops/rankine_fprops.a4c";
2 IMPORT "johnpye/fprops/heatex_pinch";
3 IMPORT "johnpye/extpy/extpy";
4 IMPORT "johnpye/fprops/regenerator_plot";
5
6 MODEL heatex_pinch_data;
7 (* this model exists simply to convey the necessary component data to the
8 external relation that solves the heat exchanger behaviour. *)
9 component IS_A symbol_constant;
10 type IS_A symbol_constant;
11
12 component_hot IS_A symbol_constant;
13 type_hot IS_A symbol_constant;
14
15 n IS_A integer_constant;
16 END heatex_pinch_data;
17
18 MODEL heatex_pinch REFINES stream_equipment;
19 inlet_hot, outlet_hot IS_A stream_node;
20
21 inlet.p, outlet.p ARE_THE_SAME;
22 inlet_hot.p, outlet_hot.p ARE_THE_SAME;
23 inlet_hot.cd, outlet_hot.cd ARE_THE_SAME;
24
25 inlet_hot.mdot, outlet_hot.mdot ARE_THE_SAME;
26 mdot_hot ALIASES inlet_hot.mdot;
27
28 hxd IS_A heatex_pinch_data;
29 hxd.component, inlet.cd.component ARE_THE_SAME;
30 hxd.component_hot, inlet_hot.cd.component ARE_THE_SAME;
31 hxd.type, inlet.cd.type ARE_THE_SAME;
32 hxd.type_hot, inlet_hot.cd.type ARE_THE_SAME;
33 n ALIASES hxd.n;
34
35 Qdot IS_A energy_rate;
36 DT_pinch "pinch temperature is the most-negative temperature difference (T_H-T_C) anywhere across the heat exchanger" IS_A delta_temperature;
37
38 outlet.h = inlet.h + Qdot/inlet.mdot;
39 outlet_hot.h = inlet_hot.h - Qdot/inlet_hot.mdot;
40
41 pinch_ext: heatex_DT_phmphmQ(
42 inlet.p, inlet.h, inlet.mdot, inlet_hot.p, inlet_hot.h, inlet_hot.mdot, Qdot : INPUT;
43 DT_pinch : OUTPUT;
44 hxd : DATA
45 );
46 METHODS
47 METHOD regenerator_plot;
48 EXTERNAL regenerator_plot_fprops(SELF);
49 END regenerator_plot;
50 END heatex_pinch;
51
52 (* test case -- HEL from brayton_split model *)
53 MODEL heatex_pinch_test REFINES heatex_pinch;
54 inlet.cd.component :== 'carbondioxide';
55 inlet.cd.type :== 'helmholtz';
56 inlet_hot.cd.component :== 'carbondioxide';
57 inlet_hot.cd.type :== 'helmholtz';
58 n :== 8;
59 METHODS
60 METHOD on_load;
61 RUN heatex_pinch::default_self;
62 (* in this configuration, we iterate to calculate the heat transfer
63 occuring for a particular pinch temperature *)
64 FIX inlet.p := 200 {bar};
65 FIX inlet_hot.p := 74 {bar};
66 FIX inlet_hot.T := 100 {K} + 273.15 {K};
67 FIX inlet.T := 31 {K} + 273.15 {K};
68 FIX mdot_hot := 1.1 {kg/s};
69 FIX mdot := 0.81 {kg/s};
70 FIX DT_pinch := 10 {K};
71 END on_load;
72 END heatex_pinch_test;

john.pye@anu.edu.au
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