Re: Type 19, Wall Modelling - Z-transfer function

["David Bradley" <bradley@xxxxxxxxxxxx>]

Dear Benoit,
   While I am not sure that this will entirely solve the problem, Type19 
knows that the first d parameter has to be 1.0 and assumes that it is. When 
entering your d coefficients, you should ignore this one and start with the 
next one: -3.1341550 in your case. If that does not entirely solve the 
problem then I would recommend that you look at TRNSYS example 5 - it 
employs a Type19 and you might check that the parameters that you are 
entering are resemble those in the example.
Cheers,
   David

At 01:28 PM 1/11/2002 +0100, Benoit Sicre wrote:
>Dear All
>
>My goal is to model a special kind of solar passive house, featuring a
>quite constant indoor temperature over the rooms. That is why I decided
>to use type 19 as a first approximation. Unfortunately the ASHRAE wall
>catalogue delivered with TRNSYS offers no kind of wall matching passive
>house yearly heat space heating requirement (according German
>regulation). I had to model myself the solid compound walls. For this, I
>used the b,c and d coefficients provided by PREP. Unluckily, I observed
>following phenomenon:
>   Despite freezing outdoor temperature and cozy 21 deg. Celsius indoor,
>after a couple of time steps my walls re-emitted a huge amount of energy
>back into the room (i.e. the heat flux through walls mistakenly went
>opposite, that means I observed heat gains instead of heat losses
>through walls).
>   Any explication, any guidance out there ?
>
>I will be very appreciative for any assistance.
>
>I appended here additional information:
>
>WALL DESCRIPTION (respectively length(m), heat conductivity (KJ/h-m-K),
>density and specific heat
>
>Outside wall resistance: 0.01638
>Finish: 0.0125 2.88 1922 .84
>Insulation layer: .32 .144 91 .84
>Lime sand brick work: .15 3.56 2002 .92
>Inside plaster: .0125 1.26 1249 1.09
>Inside wall resistance: .1044
>
>Coefficients provided by PREP:
>    0          .0000000      8.3765770      1.0000000
>    1          .0000000    -26.8543900     -3.1341550
>    2          .0000007     33.7374200      3.8412400
>    3          .0000192    -21.2426800     -2.3514930
>    4          .0000995      7.1570540       .7663302
>    5          .0001434     -1.2897260      -.1323513
>    6          .0000691       .1218972       .0117693
>    7          .0000119      -.0059488      -.0005253
>    8          .0000007       .0001414       .0000108
>
>Their implementation into my deck file:
>UNIT 19 TYPE 19 1 Room Passive House
>Param 13
>* Mode Va  K1  K2 K3 Cap   N To wo     Tmin        Tmax wmin  wmax
>   1    423 0.5 0  0  2000. 9 20 0.0075 T_room_set  145. 0.007 0.008
>Inp 11
>* T_a   w_a   T_v   mdot_v  w_v   w_I  N_people  Iact  Q_IR   Qint
>Wind
>   9,2   0,0   13,1  13,2    0,0   0,0  42,2      0,0   0,0    126,8
>9,7
>   0.    .0075 22.   204.    .0075 .25  4         4     600    0.0
>0.
>* Walls south,east,north,west
>PAR 50
>* # Type   A    rau  alpha  I  hc     Nb     Nc   Nd
>   1  1    46.75 0.7  .8     4  9.58   9      9    9
>*bn
>.0 .0 .0000007 .0000192 .0000995 .0001434 .0000691 .0000119 .0000007
>*cn
>8.3765770 -26.8543900 33.7374200 -21.2426800 7.1570540 -1.2897260
>.1218972
>-.0059488 .0001414
>*dn
>1. -3.1341550 3.8412400 -2.3514930 .7663302 -.1323513 .0117693 -.0005253
>.0000108
>   2 -1    81.37
>
>....
>
>Kind regards
>
>Benoit
>
>
>--
>Benoit SICRE
>
> >> Take a look at our new Internet-site at 
> http://www.tu-chemnitz.de/~sicre <<
>
>Theoretical Physics especially Computational Physics
>Technical University of Chemnitz
>Institute of physics
>D-09107 Chemnitz
>Germany
>
>Phone: (49) 371-531-3550
>Fax:   (49) 371-531-3233
>
>http://www.tu-chemnitz.de/~sicre

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