[esp-r] Re: Convective heat transfer coefficient

[Geissler Achim]

Qiu,
I do not quite understand your question. The "periods" mentioned in the .htc generation are "per day", as in internal loads, for example. They have nothing to do with how long you run your simulation, they are used over and over again for every simulated day.
A file with two periods - p1 from midnight to 8:00, p2 from 8:00 to midnight may look like
====
*HC_CTL for zone TheBox
*Date,Wed Feb 27 08:37:48 2008
   2 # number control intervals
   6 # number of surfaces
# (South East Wall-3 West Top-5 Base-6)
  0.00     8.00 # start and end time of interval
   4 # CEN calculation control type
*Doc,CEN user edited hc coefficients
*basetop     0.0    0.0 #  index (within the zone) of a typcial base & top
*floor     5.000  0.700  8.000 #  CEN floor upwd_inside, downwd_inside, external
*ceiling   5.000  0.700  8.000 #  CEN ceiling upwd_inside, downwd_inside, external
*slope     5.000  0.700  8.000 #  CEN sloped upwd_inside, downwd_inside, external
*wall      2.500  2.500 16.000 #  CEN wall inside, partition, external
  8.00    24.00 # start and end time of interval
   3 # adaptive calculation control type
*Doc,User supplied adaptive hc correlations
   1.  -1.  -1.   0.  99.  99.  99.  99.
  99.  99.  99.  99.  99.  99.  99.  99.
  99.  99.  99.  99.  99.  99.  99.  99.
  99.  99.  99.  99.  99.  99.  99.  99.
  99.  99.  99.  99.  99.  99.  99.  99.
  99.  99.  99.  99.  99.  99.  99.  99.
  0 0.000 0.000# Air origin zone (+ chan. width and height if Bar-Cohen corr.)
====
when period 1 uses fixed CEN values and period two has "adaptive control" on surface one, inside and no changes (I am also not quite sure, what is used, then) on all other surfaces.
(ESRU: The help texts for these features could be more informative)
A simulation run with trace on heat transfer coefficients would probably help clarify what is happening, Qiu.
Mit freundlichen Grüssen / Best regards
 
Achim Geissler
> -----Original Message-----
> From: esp-r-bounces at lists.strath.ac.uk [mailto:esp-r-
> bounces at lists.strath.ac.uk] On Behalf Of Dr.QIU
> Sent: Monday, February 25, 2008 5:08 AM
> To: esp-r
> Subject: [esp-r] Convective heat transfer coefficient
> 
> Dear all,
> 
> I want to write a  "convective heat transfer"-".htc" file.
> I have 2 queations,
> 
> 1 If my simulation period is 2 weeks even one year, but my *.cnv file
> consists of one typical day's data of each time step. Is that ok?
> 
> 2 I have alternative options when I write "convective heat transfer" file,
> one option is to give every surface's convection for the first time step,
> subsquently the next time step,  while the other option is to give each
> time-step's convection for one surface, subsquently the next surface,
> which option is correct?
> 
> thank you in advance.
> Qiu
> 
> 　　　　　　　　Dr.QIU
> 　　　　　　　　zhongqiu at cityu.edu.hk
> 　　　　　　　　　　2008-02-22
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