[TRNSYS-users] Type557a's problems

[Jeff Thornton]

<Hello, I encountered some problems when I used Type 557a, such as:
1. when I set parameters 24(i.e. insulation indicator) at 1 or 2, the
results is nearly as the same as ones with this parameters set at 0. It
seems that the parameter don't play any roles in results. >

For a system with deep boreholes, the impact of the insulation on the
surface of the field will have very little impact on the results.  Even
with NO insulation, the earth temperature more than 2 meters down is
barely affected.

<2. How to determine the initial temperature of ground or storage volume
within this type? which parameters are related to the initial
temperature?>

The model asks for several parameters that control the intial temperatures
of the storage volume and the far field.  The parameters are as follows:

Initial surface temperature --> set the intial storage volume surface
temperature
Initial thermal gradient  --> sets the inital storage volume temperature
distribution with depth

The next four parameters:

Number of preheating years
Maximum preheat temperature
Minimum preheat temperature
Preheat phase delay

allow the user to run a series of years of heating/cooling that can be
used to "pre-condition the storage volume before the simulations start and
therefore avoid a multi-year analysis.

The parameters:

Average air temperature
Amplitude of air temperature
Air temperature phase delay

are used to set the temperature distribution of the far field soil
(surrounding the storage volume) as a function of time of year and depth.

Please let us know if you have any other questions.

Jeff


Jeff Thornton
President - TESS, LLC

2916 Marketplace Drive - Suite 104
Madison WI 53719 USA

Phone: 608-274-2577
Fax: 608-278-1475
E-mail: thornton at tess-inc.com
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