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Revision 2683 - (show annotations) (download) (as text)
Fri Feb 22 01:31:37 2013 UTC (9 years, 11 months ago) by jpye
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Some updates on ascend.spec from Antonio Trande.
1 REQUIRE "johnpye/fprops/rankine_fprops.a4c";
2
3 (*------------------------------------------------------------------------------
4 REGENERATIVE RANKINE CYCLE
5 *)
6 (*
7 Add a boiler feedwater heater and two-stage turbine.
8 *)
9 MODEL rankine_regen_water;
10
11 BO IS_A boiler_simple;
12 TU1 IS_A turbine_simple;
13 BL IS_A tee; (* bleed *)
14 TU2 IS_A turbine_simple;
15 CO IS_A condenser_simple;
16 HE IS_A heater_open;
17 PU1 IS_A pump_simple;
18 PU2 IS_A pump_simple;
19
20 BO.cd.component :== 'water';
21 BO.cd.type :== 'pengrob';
22
23 (* main loop *)
24 BO.outlet, TU1.inlet ARE_THE_SAME;
25 TU1.outlet, BL.inlet ARE_THE_SAME;
26 BL.outlet, TU2.inlet ARE_THE_SAME;
27 TU2.outlet, CO.inlet ARE_THE_SAME;
28 CO.outlet, PU1.inlet ARE_THE_SAME;
29 PU1.outlet, HE.inlet ARE_THE_SAME;
30 HE.outlet, PU2.inlet ARE_THE_SAME;
31 PU2.outlet, BO.inlet ARE_THE_SAME;
32
33 (* bleed stream *)
34 BL.outlet_branch, HE.inlet_heat ARE_THE_SAME;
35 phi ALIASES BL.phi;
36 p_bleed ALIASES TU1.outlet.p;
37
38 p_bleed_ratio IS_A fraction;
39 p_bleed_ratio * (TU1.inlet.p - TU2.outlet.p) = (TU1.outlet.p - TU2.outlet.p);
40
41 mdot ALIASES BO.mdot;
42 cd ALIASES BO.inlet.cd;
43
44 T_H ALIASES BO.outlet.T;
45 T_C ALIASES CO.outlet.T;
46
47 eta IS_A fraction;
48 eta_eq:eta * (BO.Qdot_fuel) = TU1.Wdot + TU2.Wdot + PU1.Wdot + PU2.Wdot;
49
50 Wdot_TU1 ALIASES TU1.Wdot;
51 Wdot_TU2 ALIASES TU2.Wdot;
52 Wdot_PU1 ALIASES PU1.Wdot;
53 Wdot_PU2 ALIASES PU2.Wdot;
54 Qdot_fuel ALIASES BO.Qdot_fuel;
55
56 eta_carnot IS_A fraction;
57 eta_carnot_eq: eta_carnot = 1 - T_C / T_H;
58
59 eta_turb_tot IS_A fraction;
60 TU_out_is IS_A stream_state;
61 TU_out_is.cd, TU1.inlet.cd ARE_THE_SAME;
62 TU_out_is.p, TU2.outlet.p ARE_THE_SAME;
63 TU_out_is.s, TU1.inlet.s ARE_THE_SAME;
64 eta_turb_eq:eta_turb_tot * (TU1.inlet.h - TU_out_is.h) = (TU1.inlet.h - TU2.outlet.h);
65
66 (* some checking output... *)
67
68 phi_weston IS_A fraction;
69 phi_weston_eq:phi_weston * (TU1.outlet.h - PU1.outlet.h) = (PU2.inlet.h - PU1.outlet.h);
70 phi_eq:phi_weston = phi;
71
72 q_a IS_A specific_energy;
73 q_a_eq: q_a = TU1.inlet.h - PU2.outlet.h;
74
75 Wdot IS_A energy_rate;
76 Wdot_eq: Wdot = TU1.Wdot + TU2.Wdot + PU1.Wdot + PU2.Wdot;
77
78 cons_en: HE.inlet.mdot * HE.inlet.h + HE.inlet_heat.mdot * HE.inlet_heat.h = HE.outlet.mdot * HE.outlet.h;
79
80 x_turb_out ALIASES TU2.outlet.x;
81 METHODS
82 METHOD default_self;
83 RUN BO.default_self;
84 RUN TU1.default_self;
85 RUN TU2.default_self;
86 RUN CO.default_self;
87 RUN PU1.default_self;
88 RUN PU2.default_self;
89 BO.outlet.h := 4000 {kJ/kg};
90 p_bleed := 37 {bar};
91 TU1.outlet.h := 2300 {kJ/kg};
92 BL.cons_mass.included := FALSE;
93 (*HE.cons_mass.included := FALSE;*)
94 HE.cons_en.included := FALSE;
95 cons_en.included := FALSE;
96 HE.inlet.v := 100 {m^3/kg};
97 HE.inlet.p.nominal := 40 {bar};
98 HE.inlet.v.nominal := 1 {L/kg};
99 HE.inlet.h.nominal := 100 {kJ/kg};
100 END default_self;
101 METHOD solarpaces2010;
102 RUN ClearAll;
103 RUN default_self;
104 (* component efficiencies *)
105 FIX BO.eta; BO.eta := 1.0;
106 FIX TU1.eta; TU1.eta := 0.85;
107 FIX TU2.eta; TU2.eta := 0.85;
108 FIX PU1.eta; PU1.eta := 0.8;
109 FIX PU2.eta; PU2.eta := 0.8;
110 FIX Wdot; Wdot := 100 {MW};
111 (*
112 (* FIX CO.outlet.p; CO.outlet.p := 10 {kPa};*)
113 FIX CO.outlet.T; CO.outlet.T := 40 {K} + 273.15 {K};
114 FIX CO.outlet.x; CO.outlet.x := 1e-6;
115 FIX PU1.outlet.p; PU1.outlet.p := 7 {bar};
116 FIX PU2.outlet.p; PU2.outlet.p := 150 {bar};
117 PU2.outlet.p.upper_bound := 150 {bar};
118 FIX BO.outlet.T; BO.outlet.T := 580 {K} + 273.15 {K};
119 *)
120 (* turbine conditions *)
121 FIX TU1.inlet.p; TU1.inlet.p := 150 {bar};
122 FIX TU1.inlet.T; TU1.inlet.T := 580 {K} + 273.15 {K};
123 FIX TU1.outlet.p; TU1.outlet.p := 10.3 {bar};
124 FIX CO.outlet.T; CO.outlet.T := 40 {K} + 273.15 {K};
125 (* heater conditions *)
126 TU2.outlet.p := 10 {kPa};
127 (* FIX HE.outlet.p; HE.outlet.p := 0.7 {MPa}; *)
128 FIX CO.outlet.x; CO.outlet.x := 1e-6;
129 FIX HE.outlet.x; HE.outlet.x := 1e-6;
130 END solarpaces2010;
131 METHOD on_load;
132 RUN solarpaces2010;
133 (*
134 This model needs to be solved using QRSlv with convopt set to 'RELNOMSCALE'.
135 *)
136 SOLVER QRSlv;
137 OPTION convopt 'RELNOM_SCALE';
138 OPTION iterationlimit 400;
139 END on_load;
140 METHOD set_x_limit_correct_turb;
141 FREE PU2.outlet.p;
142 PU2.outlet.p.upper_bound := 150 {bar};
143 FIX TU2.outlet.x; TU2.outlet.x := 0.9;
144 (* a little corrctn to ensure we're comparing the same *overall* turbine eff *)
145 FREE TU1.eta;
146 TU2.eta := 0.823;
147 FIX eta_turb_tot; eta_turb_tot := 0.85;
148 END set_x_limit_correct_turb;
149 METHOD cycle_plot;
150 EXTERNAL cycle_plot_rankine_regen2(SELF);
151 END cycle_plot;
152 METHOD moran_ex_8_5;
153 RUN default_self;
154 (*
155 This is Example 8.5 from Moran and Shapiro, 'Fundamentals of
156 Engineering Thermodynamics', 4th Ed.
157 *)
158 RUN ClearAll;
159 (* component efficiencies *)
160 FIX BO.eta; BO.eta := 1.0;
161 FIX TU1.eta; TU1.eta := 0.85;
162 FIX TU2.eta; TU2.eta := 0.85;
163 FIX PU1.eta; PU1.eta := 1.0;
164 FIX PU2.eta; PU2.eta := 1.0;
165 (* turbine conditions *)
166 FIX TU1.inlet.p; TU1.inlet.p := 8. {MPa};
167 FIX TU1.inlet.T; TU1.inlet.T := 480 {K} + 273.15 {K};
168 FIX TU1.outlet.p; TU1.outlet.p := 0.7 {MPa};
169 FIX TU2.outlet.p; TU2.outlet.p := 0.008 {MPa};
170 (* heater conditions *)
171 (* FIX HE.outlet.p; HE.outlet.p := 0.7 {MPa}; *)
172 FIX CO.outlet.x; CO.outlet.x := 0.0001;
173 FIX HE.outlet.x; HE.outlet.x := 0.0001;
174 FIX Wdot; Wdot := 100 {MW};
175 END moran_ex_8_5;
176 METHOD self_test;
177 (* solution values to the Moran & Shapiro example 8.5 problem *)
178 ASSERT abs(eta - 0.369) < 0.001;
179 ASSERT abs((TU1.Wdot+TU2.Wdot)/mdot - 984.4{kJ/kg}) < 1 {kJ/kg};
180 ASSERT abs(mdot - 3.69e5 {kg/h}) < 0.05e5 {kg/h};
181 ASSERT abs(CO.inlet.h - 2249.3 {kJ/kg}) < 1.0 {kJ/kg};
182 END self_test;
183 METHOD weston_ex_2_6;
184 (*
185 The scenario here is example 2.6 from K Weston (op. cit.), p. 55.
186 *)
187 RUN ClearAll;
188
189 (* all ideal components *)
190 FIX BO.eta; BO.eta := 1.0;
191 FIX TU1.eta; TU1.eta := 1.0;
192 FIX TU2.eta; TU2.eta := 1.0;
193 FIX PU1.eta; PU1.eta := 1.0;
194 FIX PU2.eta; PU2.eta := 1.0;
195
196 (* mass flow rate is arbitrary *)
197 FIX mdot;
198 mdot := 10 {kg/s};
199
200 (* max pressure constraint *)
201 FIX PU2.outlet.p;
202 PU2.outlet.p := 2000 {psi};
203 PU2.outlet.h := 1400 {btu/lbm}; (* guess *)
204
205 (* boiler max temp *)
206 FIX BO.outlet.T;
207 BO.outlet.T := 1460 {R};
208 BO.outlet.h := 1400 {btu/lbm}; (* guess *)
209
210 (* intermediate temperature setting *)
211 FIX TU1.outlet.p;
212 TU1.outlet.p := 200 {psi};
213 (* FIX TU1.outlet.T;
214 TU1.outlet.T := 860 {R}; (* 400 °F *)
215 TU1.outlet.h := 3000 {kJ/kg}; (* guess *) *)
216
217 (* minimum pressure constraint *)
218 FIX CO.outlet.p;
219 CO.outlet.p := 1 {psi};
220
221 (* condenser outlet is saturated liquid *)
222 FIX CO.outlet.h;
223 CO.outlet.h := 69.73 {btu/lbm};
224
225 (* remove the redundant balance equations *)
226 HE.cons_mass.included := TRUE;
227 HE.cons_en.included := TRUE;
228 BL.cons_mass.included := FALSE;
229 phi_weston_eq.included := TRUE;
230 phi_eq.included := FALSE;
231 cons_en.included := FALSE;
232
233 (* fix the bleed ratio *)
234 FIX BL.phi;
235 BL.phi := 0.251;
236
237 (* FIX BL.outlet.h;
238 BL.outlet.h := 355.5 {btu/lbm}; *)
239
240 (**
241 these values seem to be from another problem, need to check which ...
242 ASSERT abs(TU1.inlet.s - 1.5603 {btu/lbm/R}) < 0.01 {btu/lbm/R};
243 ASSERT abs(TU1.outlet.s - 1.5603 {btu/lbm/R}) < 0.01 {btu/lbm/R};
244 ASSERT abs(TU2.outlet.s - 1.5603 {btu/lbm/R}) < 0.01 {btu/lbm/R};
245 ASSERT abs(PU1.inlet.s - 0.1326 {btu/lbm/R}) < 0.001 {btu/lbm/R};
246 ASSERT abs(PU1.outlet.s - 0.1326 {btu/lbm/R}) < 0.002 {btu/lbm/R};
247 ASSERT abs(PU2.inlet.s - 0.5438 {btu/lbm/R}) < 0.002 {btu/lbm/R};
248 ASSERT abs(PU2.outlet.s - 0.5438 {btu/lbm/R}) < 0.002 {btu/lbm/R};
249
250 ASSERT abs(TU1.inlet.h - 1474.1 {btu/lbm}) < 1.5 {btu/lbm};
251 ASSERT abs(TU1.outlet.h - 1210.0 {btu/lbm}) < 1.5 {btu/lbm};
252 ASSERT abs(TU2.outlet.h - 871.0 {btu/lbm}) < 1.5 {btu/lbm};
253 ASSERT abs(PU1.inlet.h - 69.73 {btu/lbm}) < 0.001 {btu/lbm};
254 ASSERT abs(PU1.outlet.h - 69.73 {btu/lbm}) < 1.0 {btu/lbm};
255 ASSERT abs(PU2.inlet.h - 355.5 {btu/lbm}) < 1.5 {btu/lbm};
256 ASSERT abs(PU2.outlet.h - 355.5 {btu/lbm}) < 8 {btu/lbm};
257
258 ASSERT abs(w_net - 518.1 {btu/lbm}) < 0.3 {btu/lbm};
259
260 ASSERT abs(w_net * mdot - (TU1.Wdot + TU2.Wdot)) < 1 {W};
261
262 ASSERT abs(q_a - 1118.6 {btu/lbm}) < 7 {btu/lbm};
263
264 ASSERT abs(eta - 0.463) < 0.003;
265
266 ASSERT abs(phi - 0.251) < 0.001;
267 *)
268 END weston_ex_2_6;
269 END rankine_regen_water;
270
271
272 MODEL rankine_regen_common;
273 BO IS_A boiler_simple;
274 TU IS_A turbine_simple;
275 CO IS_A condenser_simple;
276 HE IS_A heater_closed;
277 PU IS_A pump_simple;
278
279 (* main loop *)
280 BO.outlet, TU.inlet ARE_THE_SAME;
281 TU.outlet, HE.inlet_heat ARE_THE_SAME;
282 HE.outlet_heat, CO.inlet ARE_THE_SAME;
283 CO.outlet, PU.inlet ARE_THE_SAME;
284 PU.outlet, HE.inlet ARE_THE_SAME;
285 HE.outlet, BO.inlet ARE_THE_SAME;
286
287 mdot ALIASES BO.mdot;
288 cd ALIASES BO.inlet.cd;
289
290 T_H ALIASES BO.outlet.T;
291 T_C ALIASES CO.outlet.T;
292
293 eta IS_A fraction;
294 eta_eq:eta * (BO.Qdot_fuel) = TU.Wdot + PU.Wdot;
295
296 Wdot_TU ALIASES TU.Wdot;
297 Wdot_PU ALIASES PU.Wdot;
298 Qdot_fuel ALIASES BO.Qdot_fuel;
299
300 eta_carnot IS_A fraction;
301 eta_carnot_eq: eta_carnot = 1 - T_C / T_H;
302
303 Wdot IS_A energy_rate;
304 Wdot_eq: Wdot = TU.Wdot + PU.Wdot;
305
306 T_ci ALIASES HE.inlet.T;
307 T_co ALIASES HE.outlet.T;
308 T_hi ALIASES HE.inlet_heat.T;
309 T_ho ALIASES HE.outlet_heat.T;
310
311 DE_cycle "cycle energy balance, should be zero" IS_A energy_rate;
312 DE_cycle = BO.Qdot + CO.Qdot - TU.Wdot - PU.Wdot;
313
314 x_turb_out ALIASES TU.outlet.x;
315 METHODS
316 METHOD default_self;
317 RUN BO.default_self;
318 RUN TU.default_self;
319 RUN CO.default_self;
320 RUN PU.default_self;
321 RUN HE.default_self;
322 HE.cons_mass_heat.included := FALSE;
323 END default_self;
324 METHOD cycle_plot;
325 EXTERNAL cycle_plot_rankine_regen1(SELF);
326 END cycle_plot;
327 METHOD heater_plot;
328 EXTERNAL heater_closed_plot(SELF);
329 END heater_plot;
330 END rankine_regen_common;
331
332
333 MODEL rankine_regen_toluene REFINES rankine_regen_common;
334 BO.cd.component :== 'toluene';
335 BO.cd.type :== 'helmholtz';
336 HE.inlet_heat.T = HE.outlet.T + 33 {K};
337 (* HE.outlet_heat.T = HE.inlet.T + 12 {K};*)
338 METHODS
339 METHOD on_load;
340 RUN default_self;
341 FIX BO.outlet.T; BO.outlet.T := 375. {K} + 273.15 {K}; (* lowered for toluene *)
342 FIX PU.outlet.p; PU.outlet.p := 150 {bar};
343 FIX CO.outlet.T; CO.outlet.T := 40 {K} + 273.15 {K};
344 FIX CO.outlet.x; CO.outlet.x := 1e-6;
345 FIX Wdot; Wdot := 100 {MW};
346
347 FIX BO.eta; BO.eta := 1.0;
348 FIX TU.eta; TU.eta := 0.85;
349 FIX PU.eta; PU.eta := 0.8;
350
351 SOLVER QRSlv;
352 OPTION convopt 'RELNOM_SCALE';
353 OPTION iterationlimit 200;
354 END on_load;
355 METHOD default_self;
356 RUN rankine_regen_common::default_self;
357 PU.inlet.h := 400 {kJ/kg};
358 BO.outlet.h := 400 {kJ/kg};
359 CO.outlet.h := 400 {kJ/kg};
360 CO.outlet.p := 10 {kPa};
361 END default_self;
362 END rankine_regen_toluene;
363
364
365 MODEL rankine_regen_ammonia REFINES rankine_regen_common;
366 BO.cd.component :== 'ammonia';
367 BO.cd.type :== 'helmholtz';
368 METHODS
369 METHOD on_load;
370 RUN default_self;
371 FIX BO.outlet.T; BO.outlet.T := 580 {K} + 273.15 {K};
372 FIX PU.outlet.p; PU.outlet.p := 150 {bar};
373 FIX CO.outlet.T; CO.outlet.T := 40 {K} + 273.15 {K};
374 FIX CO.outlet.x; CO.outlet.x := 1e-6;
375 FIX HE.outlet.T; HE.outlet.T := 150.1 {K} + 273.15 {K};
376 FIX Wdot; Wdot := 100 {MW};
377
378 FIX BO.eta; BO.eta := 1.0;
379 FIX TU.eta; TU.eta := 0.85;
380 FIX PU.eta; PU.eta := 0.8;
381
382 SOLVER QRSlv;
383 OPTION convopt 'RELNOM_SCALE';
384 OPTION iterationlimit 200;
385 END on_load;
386 METHOD default_self;
387 RUN rankine_regen_common::default_self;
388 PU.inlet.h := 400 {kJ/kg};
389 BO.outlet.h := 400 {kJ/kg};
390 CO.outlet.h := 400 {kJ/kg};
391 CO.outlet.p := 10 {kPa};
392 END default_self;
393 END rankine_regen_ammonia;

john.pye@anu.edu.au
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