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HeatExchangerSimplified.mso @ 68

Last change on this file since 68 was 68, checked in by gerson bicca, 16 years ago
added double pipe heat exchanger model and updated eml/heat_exchangers
Property svn:eol-style set to `native` Property svn:keywords set to `Id`
File size: 18.2 KB

Rev	Line
[45]	1	#--------------------------------------------------------------------
	2	# Author: Gerson Balbueno Bicca
	3	# $Id: HeatExchangerSimplified.mso 68 2006-11-27 20:37:59Z bicca $
	4	#--------------------------------------------------------------------
[1]	5	using "HEX_Engine";
	6	#=====================================================================
	7	# Basic Models for Simplified Heat Exchangers
	8	#=====================================================================
	9	Model HeatExchangerSimplified_Basic
	10	PARAMETERS
[26]	11	ext PP as CalcObject (Brief="External Physical Properties");
[45]	12	HE as CalcObject (Brief="STHE Calculations",File="heatex");
[26]	13	ext NComp as Integer (Brief="Number of Components");
	14	M(NComp) as molweight (Brief="Component Mol Weight");
[1]	15
	16	VARIABLES
	17
	18	in Inlet as Inlet_Main_Stream; # Hot and Cold Inlets
	19	out Outlet as Outlet_Main_Stream; # Hot and Cold Outlets
	20	Properties as Main_Properties; # Hot and Cold Properties
	21	Details as Details_Main;
	22	PressureDrop as Main_Pdrop;
	23
	24	SET
	25
	26	M = PP.MolecularWeight();
	27
	28	EQUATIONS
	29
	30	"Hot Stream Average Temperature"
	31	Properties.Hot.Average.T = 0.5Inlet.Hot.T + 0.5Outlet.Hot.T;
	32
	33	"Cold Stream Average Temperature"
	34	Properties.Cold.Average.T = 0.5Inlet.Cold.T + 0.5Outlet.Cold.T;
	35
	36	"Hot Stream Average Pressure"
	37	Properties.Hot.Average.P = 0.5Inlet.Hot.P+0.5Outlet.Hot.P;
	38
	39	"Cold Stream Average Pressure"
	40	Properties.Cold.Average.P = 0.5Inlet.Cold.P+0.5Outlet.Cold.P;
	41
	42	"Cold Stream Wall Temperature"
	43	Properties.Cold.Wall.Twall = 0.5Properties.Hot.Average.T + 0.5Properties.Cold.Average.T;
	44
	45	"Hot Stream Wall Temperature"
	46	Properties.Hot.Wall.Twall = 0.5Properties.Hot.Average.T + 0.5Properties.Cold.Average.T;
	47
	48	"Hot Stream Average Molecular Weight"
	49	Properties.Hot.Average.Mw = sum(M*Inlet.Hot.z);
	50
	51	"Cold Stream Average Molecular Weight"
	52	Properties.Cold.Average.Mw = sum(M*Inlet.Cold.z);
	53
	54
	55	if Inlet.Cold.v equal 0
[68]	56
[1]	57	then
[68]	58
	59	"Cold Stream Average Heat Capacity"
	60	Properties.Cold.Average.Cp = PP.LiquidCp(Properties.Cold.Average.T,Properties.Cold.Average.P,Inlet.Cold.z);
[1]	61
[68]	62	"Cold Stream Inlet Heat Capacity"
	63	Properties.Cold.Inlet.Cp = PP.LiquidCp(Inlet.Cold.T,Inlet.Cold.P,Inlet.Cold.z);
[1]	64
[68]	65	"Cold Stream Outlet Heat Capacity"
	66	Properties.Cold.Outlet.Cp = PP.LiquidCp(Outlet.Cold.T,Outlet.Cold.P,Outlet.Cold.z);
[1]	67
[68]	68	"Cold Stream Average Mass Density"
	69	Properties.Cold.Average.rho = PP.LiquidDensity(Properties.Cold.Average.T,Properties.Cold.Average.P,Inlet.Cold.z);
[1]	70
[68]	71	"Cold Stream Inlet Mass Density"
	72	Properties.Cold.Inlet.rho = PP.LiquidDensity(Inlet.Cold.T,Inlet.Cold.P,Inlet.Cold.z);
	73
	74	"Cold Stream Outlet Mass Density"
	75	Properties.Cold.Outlet.rho = PP.LiquidDensity(Outlet.Cold.T,Outlet.Cold.P,Outlet.Cold.z);
	76
	77	"Cold Stream Average Viscosity"
	78	Properties.Cold.Average.Mu = PP.LiquidViscosity(Properties.Cold.Average.T,Properties.Cold.Average.P,Inlet.Cold.z);
	79
	80	"Cold Stream inlet Viscosity"
	81	Properties.Cold.Inlet.Mu = PP.LiquidViscosity(Inlet.Cold.T,Inlet.Cold.P,Inlet.Cold.z);
[1]	82
[68]	83	"Cold Stream Outlet Viscosity"
	84	Properties.Cold.Outlet.Mu = PP.LiquidViscosity(Outlet.Cold.T,Outlet.Cold.P,Outlet.Cold.z);
[1]	85
[68]	86	"Cold Stream Average Conductivity"
	87	Properties.Cold.Average.K = PP.LiquidThermalConductivity(Properties.Cold.Average.T,Properties.Cold.Average.P,Inlet.Cold.z);
[1]	88
[68]	89	"Cold Stream Inlet Conductivity"
	90	Properties.Cold.Inlet.K = PP.LiquidThermalConductivity(Inlet.Cold.T,Inlet.Cold.P,Inlet.Cold.z);
[1]	91
[68]	92	"Cold Stream Outlet Conductivity"
	93	Properties.Cold.Outlet.K = PP.LiquidThermalConductivity(Outlet.Cold.T,Outlet.Cold.P,Outlet.Cold.z);
	94
	95	"Cold Stream Heat Capacity at Wall Temperature"
	96	Properties.Cold.Wall.Cp = PP.LiquidCp(Properties.Cold.Wall.Twall,Properties.Cold.Average.P,Inlet.Cold.z);
	97
	98	"Cold Stream Viscosity at Wall Temperature"
	99	Properties.Cold.Wall.Mu = PP.LiquidViscosity(Properties.Cold.Wall.Twall,Properties.Cold.Average.P,Inlet.Cold.z);
	100
	101	"Cold Stream Conductivity at Wall Temperature"
	102	Properties.Cold.Wall.K = PP.LiquidThermalConductivity(Properties.Cold.Wall.Twall,Properties.Cold.Average.P,Inlet.Cold.z);
	103
	104
[1]	105	else
	106
[68]	107	"Cold Stream Average Heat Capacity"
[1]	108	Properties.Cold.Average.Cp = PP.VapourCp(Properties.Cold.Average.T,Properties.Cold.Average.P,Inlet.Cold.z);
[68]	109
	110	"Cold Stream Inlet Heat Capacity"
[1]	111	Properties.Cold.Inlet.Cp = PP.VapourCp(Inlet.Cold.T,Inlet.Cold.P,Inlet.Cold.z);
[68]	112
	113	"Cold Stream Outlet Heat Capacity"
[1]	114	Properties.Cold.Outlet.Cp = PP.VapourCp(Outlet.Cold.T,Outlet.Cold.P,Outlet.Cold.z);
	115
[68]	116	"Cold Stream Average Mass Density"
	117	Properties.Cold.Average.rho = PP.VapourDensity(Properties.Cold.Average.T,Properties.Cold.Average.P,Inlet.Cold.z);
[1]	118
[68]	119	"Cold Stream Inlet Mass Density"
	120	Properties.Cold.Inlet.rho = PP.VapourDensity(Inlet.Cold.T,Inlet.Cold.P,Inlet.Cold.z);
[1]	121
[68]	122	"Cold Stream Outlet Mass Density"
	123	Properties.Cold.Outlet.rho = PP.VapourDensity(Outlet.Cold.T,Outlet.Cold.P,Outlet.Cold.z);
	124
	125	"Cold Stream Average Viscosity "
	126	Properties.Cold.Average.Mu = PP.VapourViscosity(Properties.Cold.Average.T,Properties.Cold.Average.P,Inlet.Cold.z);
	127
	128	"Cold Stream Inlet Viscosity "
	129	Properties.Cold.Inlet.Mu = PP.VapourViscosity(Inlet.Cold.T,Inlet.Cold.P,Inlet.Cold.z);
	130
	131	"Cold Stream Outlet Viscosity "
	132	Properties.Cold.Outlet.Mu = PP.VapourViscosity(Outlet.Cold.T,Outlet.Cold.P,Outlet.Cold.z);
	133
	134	"Cold Stream Average Conductivity "
	135	Properties.Cold.Average.K = PP.VapourThermalConductivity(Properties.Cold.Average.T,Properties.Cold.Average.P,Inlet.Cold.z);
	136
	137	"Cold Stream Inlet Conductivity "
	138	Properties.Cold.Inlet.K = PP.VapourThermalConductivity(Inlet.Cold.T,Inlet.Cold.P,Inlet.Cold.z);
	139
	140	"Cold Stream Outlet Conductivity "
	141	Properties.Cold.Outlet.K = PP.VapourThermalConductivity(Outlet.Cold.T,Outlet.Cold.P,Outlet.Cold.z);
[1]	142
[68]	143	"Cold Stream Heat Capacity at Wall Temperature"
	144	Properties.Cold.Wall.Cp = PP.VapourCp(Properties.Cold.Wall.Twall,Properties.Cold.Average.P,Inlet.Cold.z);
[1]	145
	146
[68]	147	"Cold Stream Viscosity at Wall Temperature"
	148	Properties.Cold.Wall.Mu = PP.VapourViscosity(Properties.Cold.Wall.Twall,Properties.Cold.Average.P,Inlet.Cold.z);
[1]	149
[68]	150	"Cold Stream Conductivity at Wall Temperature"
	151	Properties.Cold.Wall.K = PP.VapourThermalConductivity(Properties.Cold.Wall.Twall,Properties.Cold.Average.P,Inlet.Cold.z);
[1]	152
	153
	154
	155	end
	156
	157	if Inlet.Hot.v equal 0
	158
	159	then
	160
[68]	161	"Hot Stream Average Heat Capacity"
[1]	162	Properties.Hot.Average.Cp = PP.LiquidCp(Properties.Hot.Average.T,Properties.Hot.Average.P,Inlet.Hot.z);
[68]	163
	164	"Hot Stream Inlet Heat Capacity"
[1]	165	Properties.Hot.Inlet.Cp = PP.LiquidCp(Inlet.Hot.T,Inlet.Hot.P,Inlet.Hot.z);
[68]	166
	167	"Hot Stream Outlet Heat Capacity"
[1]	168	Properties.Hot.Outlet.Cp = PP.LiquidCp(Outlet.Hot.T,Outlet.Hot.P,Outlet.Hot.z);
	169
[68]	170	"Hot Stream Average Mass Density"
[1]	171	Properties.Hot.Average.rho = PP.LiquidDensity(Properties.Hot.Average.T,Properties.Hot.Average.P,Inlet.Hot.z);
[68]	172
	173	"Hot Stream Inlet Mass Density"
[1]	174	Properties.Hot.Inlet.rho = PP.LiquidDensity(Inlet.Hot.T,Inlet.Hot.P,Inlet.Hot.z);
[68]	175
	176	"Hot Stream Outlet Mass Density"
[1]	177	Properties.Hot.Outlet.rho = PP.LiquidDensity(Outlet.Hot.T,Outlet.Hot.P,Outlet.Hot.z);
	178
[68]	179	"Hot Stream Average Viscosity"
[1]	180	Properties.Hot.Average.Mu = PP.LiquidViscosity(Properties.Hot.Average.T,Properties.Hot.Average.P,Inlet.Hot.z);
[68]	181
	182	"Hot Stream Inlet Viscosity"
[1]	183	Properties.Hot.Inlet.Mu = PP.LiquidViscosity(Inlet.Hot.T,Inlet.Hot.P,Inlet.Hot.z);
[68]	184
	185	"Hot Stream Outlet Viscosity"
[1]	186	Properties.Hot.Outlet.Mu = PP.LiquidViscosity(Outlet.Hot.T,Outlet.Hot.P,Outlet.Hot.z);
	187
[68]	188	"Hot Stream Average Conductivity"
[1]	189	Properties.Hot.Average.K = PP.LiquidThermalConductivity(Properties.Hot.Average.T,Properties.Hot.Average.P,Inlet.Hot.z);
[68]	190
	191	"Hot Stream Inlet Conductivity"
[45]	192	Properties.Hot.Inlet.K = PP.LiquidThermalConductivity(Inlet.Hot.T,Inlet.Hot.P,Inlet.Hot.z);
[68]	193
	194	"Hot Stream Outlet Conductivity"
[1]	195	Properties.Hot.Outlet.K = PP.LiquidThermalConductivity(Outlet.Hot.T,Outlet.Hot.P,Outlet.Hot.z);
	196
[68]	197	"Hot Stream Heat Capacity at Wall Temperature"
[45]	198	Properties.Hot.Wall.Cp = PP.LiquidCp(Properties.Hot.Wall.Twall,Properties.Hot.Average.P,Inlet.Hot.z);
[1]	199
[68]	200	"Hot Stream Viscosity at Wall Temperature"
[45]	201	Properties.Hot.Wall.Mu = PP.LiquidViscosity(Properties.Hot.Wall.Twall,Properties.Hot.Average.P,Inlet.Hot.z);
[1]	202
[68]	203	"Hot Stream Conductivity at Wall Temperature"
[45]	204	Properties.Hot.Wall.K = PP.LiquidThermalConductivity(Properties.Hot.Wall.Twall,Properties.Hot.Average.P,Inlet.Hot.z);
[1]	205
	206
	207	else
	208
[68]	209	"Hot Stream Average Heat Capacity"
[1]	210	Properties.Hot.Average.Cp = PP.VapourCp(Properties.Hot.Average.T,Properties.Hot.Average.P,Inlet.Hot.z);
[68]	211
	212	"Hot Stream Inlet Heat Capacity"
[1]	213	Properties.Hot.Inlet.Cp = PP.VapourCp(Inlet.Hot.T,Inlet.Hot.P,Inlet.Hot.z);
[68]	214
	215	"Hot Stream Outlet Heat Capacity"
[1]	216	Properties.Hot.Outlet.Cp = PP.VapourCp(Outlet.Hot.T,Outlet.Hot.P,Outlet.Hot.z);
	217
[68]	218	"Hot Stream Average Mass Density"
[1]	219	Properties.Hot.Average.rho = PP.VapourDensity(Properties.Hot.Average.T,Properties.Hot.Average.P,Inlet.Hot.z);
[68]	220
	221	"Hot Stream Inlet Mass Density"
[1]	222	Properties.Hot.Inlet.rho = PP.VapourDensity(Inlet.Hot.T,Inlet.Hot.P,Inlet.Hot.z);
[68]	223
	224	"Hot Stream Outlet Mass Density"
[1]	225	Properties.Hot.Outlet.rho = PP.VapourDensity(Outlet.Hot.T,Outlet.Hot.P,Outlet.Hot.z);
	226
[68]	227	"Hot Stream Average Viscosity"
[1]	228	Properties.Hot.Average.Mu = PP.VapourViscosity(Properties.Hot.Average.T,Properties.Hot.Average.P,Inlet.Hot.z);
[68]	229
	230	"Hot Stream Inlet Viscosity"
[1]	231	Properties.Hot.Inlet.Mu = PP.VapourViscosity(Inlet.Hot.T,Inlet.Hot.P,Inlet.Hot.z);
[68]	232
	233	"Hot Stream Outlet Viscosity"
[1]	234	Properties.Hot.Outlet.Mu = PP.VapourViscosity(Outlet.Hot.T,Outlet.Hot.P,Outlet.Hot.z);
	235
[68]	236	"Hot Stream Average Conductivity"
[1]	237	Properties.Hot.Average.K = PP.VapourThermalConductivity(Properties.Hot.Average.T,Properties.Hot.Average.P,Inlet.Hot.z);
[68]	238
	239	"Hot Stream Inlet Conductivity"
[45]	240	Properties.Hot.Inlet.K = PP.VapourThermalConductivity(Inlet.Hot.T,Inlet.Hot.P,Inlet.Hot.z);
[68]	241
	242	"Hot Stream Outlet Conductivity"
[1]	243	Properties.Hot.Outlet.K = PP.VapourThermalConductivity(Outlet.Hot.T,Outlet.Hot.P,Outlet.Hot.z);
	244
[68]	245	"Hot Stream Heat Capacity at Wall Temperature"
[45]	246	Properties.Hot.Wall.Cp = PP.VapourCp(Properties.Hot.Wall.Twall,Properties.Hot.Average.P,Inlet.Hot.z);
[1]	247
[68]	248	"Hot Stream Viscosity at Wall Temperature"
[45]	249	Properties.Hot.Wall.Mu = PP.VapourViscosity(Properties.Hot.Wall.Twall,Properties.Hot.Average.P,Inlet.Hot.z);
[1]	250
[68]	251	"Hot Stream Conductivity at Wall Temperature"
[45]	252	Properties.Hot.Wall.K = PP.VapourThermalConductivity(Properties.Hot.Wall.Twall,Properties.Hot.Average.P,Inlet.Hot.z);
[1]	253
	254
	255	end
	256
[68]	257
[1]	258	#=====================================================================
	259	# Thermal Details
	260	#=====================================================================
	261	"Hot Stream Heat Capacity"
	262	Details.Ch =Inlet.Hot.F*Properties.Hot.Average.Cp;
	263
	264	"Cold Stream Heat Capacity"
	265	Details.Cc =Inlet.Cold.F*Properties.Cold.Average.Cp;
	266
[45]	267	"Minimum Heat Capacity"
	268	Details.Cmin = min([Details.Ch,Details.Cc]);
	269
	270	"Maximum Heat Capacity"
	271	Details.Cmax = max([Details.Ch,Details.Cc]);
	272
	273	"Heat Capacity Ratio"
	274	Details.Cr = Details.Cmin/Details.Cmax;
[1]	275	#=====================================================================
	276	# Energy Balance
	277	#=====================================================================
	278	"Energy Balance Hot Stream"
	279	Details.Q = Inlet.Hot.F*(Inlet.Hot.h-Outlet.Hot.h);
	280
	281	"Energy Balance Cold Stream"
	282	Details.Q =-Inlet.Cold.F*(Inlet.Cold.h-Outlet.Cold.h);
	283
	284	#=====================================================================
	285	# Material Balance
	286	#=====================================================================
	287	"Flow Mass Inlet Cold Stream"
	288	Properties.Cold.Inlet.Fw = sum(MInlet.Cold.z)Inlet.Cold.F;
	289
	290	"Flow Mass Outlet Cold Stream"
	291	Properties.Cold.Outlet.Fw = sum(MOutlet.Cold.z)Outlet.Cold.F;
	292
	293	"Flow Mass Inlet Hot Stream"
	294	Properties.Hot.Inlet.Fw = sum(MInlet.Hot.z)Inlet.Hot.F;
	295
	296	"Flow Mass Outlet Hot Stream"
	297	Properties.Hot.Outlet.Fw = sum(MOutlet.Hot.z)Outlet.Hot.F;
	298
	299	"Molar Balance Hot Stream"
	300	Inlet.Hot.F = Outlet.Hot.F;
	301
	302	"Molar Balance Cold Stream"
	303	Inlet.Cold.F = Outlet.Cold.F;
	304
	305	#======================================
	306	# Constraints
	307	#======================================
	308	"Hot Stream Molar Fraction Constraint"
	309	Outlet.Hot.z=Inlet.Hot.z;
	310
	311	"Cold Stream Molar Fraction Constraint"
	312	Outlet.Cold.z=Inlet.Cold.z;
	313
	314	"No Phase Change In Cold Stream"
	315	Inlet.Cold.v=Outlet.Cold.v;
	316
	317	"No Phase Change In Hot Stream"
	318	Inlet.Hot.v=Outlet.Hot.v;
	319
	320	#======================================
	321	# Pressure Drop
	322	#======================================
	323
	324	"Pressure Drop Hot Stream"
	325	Outlet.Hot.P = Inlet.Hot.P - PressureDrop.Hot.Pdrop;
	326
	327	"Pressure Drop Cold Stream"
	328	Outlet.Cold.P = Inlet.Cold.P - PressureDrop.Cold.Pdrop;
	329
	330	"Fraction of Inlet Pressure : Hot Stream"
	331	PressureDrop.Hot.Pdrop = Inlet.Hot.P*PressureDrop.Hot.FPdrop;
	332
	333	"Fraction of Inlet Pressure : Cold Stream"
	334	PressureDrop.Cold.Pdrop = Inlet.Cold.P*PressureDrop.Cold.FPdrop;
	335
	336
	337	end
	338
	339	Model Heatex_Basic_NTU as HeatExchangerSimplified_Basic
	340	#=====================================================================
	341	# Basic Model for Heat Exchangers - NTU Method
	342	#=====================================================================
	343	VARIABLES
	344
	345	Eft as positive (Brief="Effectiveness",Default=0.05,Lower=1e-8);
	346
	347	EQUATIONS
	348
	349	"Energy Balance"
	350	Details.Q = EftDetails.Cmin(Inlet.Hot.T-Inlet.Cold.T);
	351
	352
	353	end
	354
	355	Model Heatex_Basic_LMTD as HeatExchangerSimplified_Basic
	356	#=====================================================================
	357	# Basic Model for Heat Exchangers - LMTD Method
	358	#=====================================================================
	359	VARIABLES
	360
[45]	361	DT0 as temp_delta (Brief="Temperature Difference at Inlet",Lower=1);
	362	DTL as temp_delta (Brief="Temperature Difference at Outlet",Lower=1);
[26]	363	LMTD as temp_delta (Brief="Logarithmic Mean Temperature Difference",Lower=1);
	364	Fc as positive (Brief="LMTD Correction Factor",Lower=0.5);
[45]	365	MTD as temp_delta (Brief="Mean Temperature Difference",Lower=1);
[1]	366
	367	EQUATIONS
[45]	368	#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
	369	# Log Mean Temperature Difference
	370	#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
	371	if abs(DT0 - DTL) > 0.05*max(abs([DT0,DTL]))
	372
	373	then
	374	"Log Mean Temperature Difference"
	375	LMTD= (DT0-DTL)/ln(DT0/DTL);
[1]	376
[45]	377	else
	378
	379	if DT0*DTL equal 0
	380
	381	then
	382	"Log Mean Temperature Difference"
	383	LMTD = 0.5*(DT0+DTL);
	384
	385	else
	386	"Log Mean Temperature Difference"
	387	LMTD = 0.5(DT0+DTL)(1-(DT0-DTL)^2/(DT0DTL)(1+(DT0-DTL)^2/(DT0*DTL)/2)/12);
	388
	389	end
	390
	391	end
	392
[1]	393	"Exchange Surface Area"
[26]	394	Details.Q = Details.UDetails.AMTD;
[1]	395
	396	"Mean Temperature Difference"
	397	MTD = Fc*LMTD;
	398
	399	end
	400
	401
	402	#=====================================================================
	403	# Concrete Models for Simplified Heat Exchangers
	404	#=====================================================================
	405
	406	#=====================================================================
	407	# LMTD Method
	408	#=====================================================================
	409
	410	Model HeatExchanger_LMTD as Heatex_Basic_LMTD
	411
[45]	412	PARAMETERS
	413
	414	Side as Integer (Brief="Flow Direction",Lower=0,Upper=1);
	415
	416	SET
	417
	418	Side = HE.FlowDir(); # Return Flow Direction
	419
[1]	420	EQUATIONS
[45]	421	#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
	422	# Flow Direction
	423	#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
	424	if Side equal 0
	425	#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
	426	# Cocurrent Flow
	427	#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
	428	then
	429	"Temperature Difference at Inlet"
	430	DT0 = Inlet.Hot.T - Inlet.Cold.T;
[1]	431
[45]	432	"Temperature Difference at Outlet"
	433	DTL = Outlet.Hot.T - Outlet.Cold.T;
[1]	434
[45]	435	else
	436	#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
	437	# Counter Flow
	438	#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
	439	"Temperature Difference at Inlet"
	440	DT0 = Inlet.Hot.T - Outlet.Cold.T;
	441
	442	"Temperature Difference at Outlet"
	443	DTL = Outlet.Hot.T - Inlet.Cold.T;
[1]	444	end
	445
[45]	446	end
	447
[1]	448	Model E_Shell_LMTD as Heatex_Basic_LMTD
	449	#=====================================================================
	450	# Shell and Tubes Heat Exchanger with 1 shell pass - LMTD Method
	451	#=====================================================================
	452	EQUATIONS
[45]	453	"Temperature Difference at Inlet"
	454	DT0 = Inlet.Hot.T - Outlet.Cold.T;
[1]	455
[45]	456	"Temperature Difference at Outlet"
	457	DTL = Outlet.Hot.T - Inlet.Cold.T;
	458
[1]	459	"LMTD Correction Factor"
	460	Fc = HE.EshellCorrectionFactor(Inlet.Hot.T,Outlet.Hot.T,Inlet.Cold.T,Outlet.Cold.T);
	461
	462	end
	463
	464	Model F_Shell_LMTD as Heatex_Basic_LMTD
	465	#=====================================================================
	466	# Shell and Tubes Heat Exchanger with 2 shell passes - LMTD Method
	467	#=====================================================================
	468	EQUATIONS
[45]	469	"Temperature Difference at Inlet"
	470	DT0 = Inlet.Hot.T - Outlet.Cold.T;
[1]	471
[45]	472	"Temperature Difference at Outlet"
	473	DTL = Outlet.Hot.T - Inlet.Cold.T;
	474
[1]	475	"LMTD Correction Factor"
	476	Fc = HE.FshellCorrectionFactor(Inlet.Hot.T,Outlet.Hot.T,Inlet.Cold.T,Outlet.Cold.T);
	477
	478	end
	479
	480	#=====================================================================
	481	# NTU Method
	482	#=====================================================================
	483
	484	Model HeatExchanger_NTU as Heatex_Basic_NTU
[68]	485
	486	PARAMETERS
[1]	487
[68]	488	Side as Integer (Brief="Flow Direction",Lower=0,Upper=1);
	489
	490	SET
	491
	492	Side = HE.FlowDir(); # Return Flow Direction
	493
[1]	494	EQUATIONS
[68]	495
	496	if Details.Cr equal 0
	497
	498	then
[1]	499	"Effectiveness"
[68]	500	Eft = 1-exp(-Details.NTU);
[1]	501
[68]	502	else
	503
	504	if Side equal 0
	505
	506	then
	507	"Effectiveness in Cocurrent Flow"
	508	Eft = (1-exp(-Details.NTU*(1+Details.Cr)))/(1+Details.Cr);
	509
	510	else
	511
	512	if Details.Cr equal 1
	513
	514	then
	515	"Effectiveness in Counter Flow"
	516	Eft = Details.NTU/(1+Details.NTU);
	517
	518	else
	519	"Effectiveness in Counter Flow"
	520	Eft(1-Details.Crexp(-Details.NTU(1-Details.Cr))) = (1-exp(-Details.NTU(1-Details.Cr)));
	521
[1]	522	end
	523
[68]	524	end
	525
	526
	527	end
	528
	529
	530	end
	531
[1]	532	Model E_Shell_NTU as Heatex_Basic_NTU
	533	#=====================================================================
	534	# Shell and Tubes Heat Exchanger with 1 shell pass - NTU Method
	535	#=====================================================================
	536	EQUATIONS
	537	"TEMA E Shell Effectiveness"
	538	Eft = 2(1+Details.Cr+sqrt(1+Details.Cr^2)((1+exp(-Details.NTUsqrt(1+Details.Cr^2)))/(1-exp(-Details.NTUsqrt(1+Details.Cr^2)))) )^-1;
	539
	540	end
	541
	542	Model F_Shell_NTU as Heatex_Basic_NTU
	543	#=====================================================================
	544	# Shell and Tubes Heat Exchanger with 2 shell passes - NTU Method
	545	#=====================================================================
	546	VARIABLES
	547
	548	Eft1 as positive (Brief="Effectiveness Correction",Lower=0.01,Upper=1,Default=0.5);
	549
	550	EQUATIONS
	551
	552	"Effectiveness Correction"
	553	Eft1 = 2(1+Details.Cr+sqrt(1+Details.Cr^2)((1+exp(-Details.NTUsqrt(1+Details.Cr^2)))/(1-exp(-Details.NTUsqrt(1+Details.Cr^2)))) )^-1;
	554
	555	"TEMA F Shell Effectiveness"
	556	Eft = ( ((1-Eft1Details.Cr)/(1-Eft1))^2 -1 )( ((1-Eft1*Details.Cr)/(1-Eft1))^2 - Details.Cr )^-1;
	557
	558	end

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