یک مدل شبیه سازی برای تعیین صرفه جویی انرژی تهویه هوا در ساختمان اداره

Energy saving and energy efficient equipment are attracting a lot of attention due to the escalating energy costs world wide. Selection of Heating, Ventilation and Air-Conditioning (HVAC) system for buildings is considered to play a vital role in energy consumption. However, proper selection of such a system depends primarily on an accurate cooling load calculation method. ASHRAE has developed different methods to estimate the accuracy of cooling load calculations. In this paper a method based on the finite difference technique is implemented to estimate the cooling load in an office building. The office building is cooled by a ceiling radiant cooling panel (CRCP) coupled with fan coil unit (FCU) using 100% fresh air. The simulation model of the office building showed that significant energy reduction could be obtained when using a ceiling radiant cooling panel.

To apply an explicit method in practice, consider the nodal subvolume of Figure 1. denotes to the rate of heat addition (external or internal) to the node. This element can be considered as an arbitrary subvolume of outer part of a building wall. Assume one dimensional flow and node i represents the subvolume having thermal capacity Ci, and connected by resistance Rij1 and Rij2 which stand for convective and conductive resistances respectively. If the node i is exposed to the solar heat input qi and has a temperature Tt at time t, then for a time interval Δt the quantity of heat Q entering the node i is expressed as [1]:

From the previous study the following conclusion can be drawn as follows: Selection of Heating, Ventilation and Air-Conditioning (HVAC) system for buildings is considered to play a vital role in energy consumption. The simulation model of the office building showed that significant energy reduction could be obtained when using a ceiling radiant cooling panel. The above comparisons (figure 15) have shown that the CRCP/DOAS system saves 17.3% energy over the VAV system with recirculation air. On the other hand, the CRCP/DOAS system with 100% fresh air can save more than 26.1% of input power over a VAV system with 100% fresh air. Simulation model should be used to evaluate cooling load calculation of the buildings.