Civil Engineering Reference
In-Depth Information
Tables 7.7
and
7.8
show the values of load match index and grid interaction
index of the LH, which were evaluated for different time bases.
Table 7.7
Effect of time base on the load match index
36
37
39
Daily
65
72
76
Monthly
69
79
80
Table 7.8
Effect of time base on the grid interaction index
Grid Interaction Index (
Eq. (7.5)
) 2009 (%) 2010 (%) 2011 (%)
Hourly
32
31
32
Daily
38
39
38
Monthly
40
50
51
7.3.6 Features and Limits of the Employed Model
The thermal building simulation in non-steady-state conditions (Beccali
et
al.
, 2003, 2005a, 2005b; Cellura
et al.
, 2010b) of the LH was developed
in TRNSYS 16.1 (Bradley and Kummert, 2005). The model deals with a
large number of variables; it shows some limits and does not take into
consideration the aspects summarized below:
1. The LH thermal plant is extremely complex. Therefore, many
recirculating nodes have been omitted in order to have a clearer,
simpler, and faster simulation;
2. TRNSYS offers limited tools to simulate the natural ventilation
behaviors of the LH. Schedules to model natural ventilation have been
assumed and used for the simulations;
3. Infiltration can be estimated with Type 571. It uses the following
formula to determine infiltration in air changes per hour (ASHRAE,
2009):
Search WWH ::
Custom Search