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[EnergyPlus_Support] A question about CTFs
Dear all:
I want to use the CTF to calculate the heat transfer through the wall.
The form of the conduction transfer function solution is below equation:
Current Inside Conductive Flux = (Inside Term 0) * (Current Inside Face Temperature)
+(Inside Term 1) * (Previous Inside Face Temperature)
+(Inside Term 2) * (Inside Face Temperature 2 Time Steps Ago)
+(Inside Term 3) * (Inside Face Temperature 3 Time Steps Ago)
+ ...
+(Cross Term 0) * (Current Outside Face Temperature)
+(Cross Term 1) * (Previous Outside Face Temperature)
+(Cross Term 2) * (Outside Face Temperature 2 Time Steps Ago)
+(Cross Term 3) * (Outside Face Temperature 3 Time Steps Ago)
+ ...
+(Flux Term 1) * (Previous Inside Face Flux)
+(Flux Term 2) * (Inside Face Flux 2 Time Steps Ago)
+(Flux Term 3) * (Inside Face Flux 3 Time Steps Ago)
+ ...
and I get the CTFs in *.eio file, the value of CTFs is shown below:
Construction,EXTERWALL1_CONCRETE_2100, 4, 18, 0.167, 0.6033 , 0.900, 0.900, 0.700, 0.700,Rough
Material,SLUSH MORTAR, 0.0200, 0.930, 1800.000, 1062.000, 0.2151E-01
Material,EPS1, 0.0500, 0.040, 15.000, 1400.000, 1.250
Material,CONCRETE1_2100, 0.2000, 1.280, 2100.000, 920.000, 0.1562
Material,LIME MORTAR, 0.2000, 0.870, 1700.000, 1050.000, 0.2299
CTF,18,0.15049167E-07,-0.21682487E-18,0.67069711E-13, -0.15626633E-14
CTF,17,-0.26448243E-05,-0.15318301E-18,-0.66319653E-07, 0.15918648E-08
CTF,16, 0.15333157E-03,0.16905925E-18, 0.94242000E-05, -0.22710729E-06
CTF,15, -0.44145301E-02,-0.84324973E-17, -0.39650340E-03, 0.96432515E-05
CTF, 14,0.76655816E-01, 0.12202644E-14, 0.87375554E-02, -0.21485780E-03
CTF, 13, -0.88895541, 0.91721351E-13, -0.12139338 , 0.30224184E-02
CTF, 12, 7.3048382 , 0.37306641E-11, 1.1614489 , -0.29318711E-01
CTF, 11, -44.119610, 0.64830792E-10, -8.0375559 , 0.20599150
CTF, 10, 200.43401 , 0.56642175E-09, 41.419788 , -1.0792574
CTF, 9, -694.62120 ,0.25311226E-08, -161.69510 , 4.2897295
CTF, 8, 1849.9195 ,0.60119969E-08, 482.45677 , -13.050737
CTF, 7, -3792.0595 , 0.74054537E-08, -1102.8340 , 30.461354
CTF, 6, 5958.2866 , 0.47728248E-08,1923.9766, -54.337180
CTF, 5, -7099.4379 , 0.13441164E-08, -2534.5777 , 73.285778
CTF, 4, 6290.1754 , 0.27272593E-09, 2472.3625 , -73.274261
CTF, 3, -4008.4518 , -0.53020291E-10, -1727.2414 , 52.524960
CTF, 2, 1733.9872 , 0.29931675E-10, 815.66186 , -25.472846
CTF, 1, -455.33483 , -0.87445859E-11,-232.84147 , 7.4729689
CTF, 0, 54.733855 , 0.11687668E-11, 30.301279
The C languange source code of my program is shown below:
for(t=0;t<TotalNum;t++)
{
ZTi=0;
YTo=0;
Qqi=0;
for(j=1;j<=N;j++)
{
if(t-j>=0)
{
ZTi=ZTi+Z[j]*TI[t-j];
YTo=YTo+Y[j]*TO[t-j];
Qqi=Qqi+Q[j]*QI[t-j];
}
}
QI[t]=0-Z[0]*TI[t]-ZTi+Y[0]*TO[t]+YTo+Qqi;
// printf("%f\t%f\t%f\n",-Z[0]*TI[t],-ZTi,YTo,,Qqi);
}
After run this program, the result confuses me, because the heat flue is increasing with time increasing.
Anyone can told me why?
Wang Lei
[Non-text portions of this message have been removed]
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