ASHRAE AB-10-012

Abstract

<strong>INTRODUCTION</strong> <br>The DX air cooling coil model is a key module in modeling or simulating an overall cooling system to facilitate the system's design, operation, and maintenance. Generally, all engineering simulation or modeling programs include an element modeling module for DX cooling coils, but individual programs may use different modeling methods and thus have different performance. For example, EnergyPlus is one of the most popular building energy simulation tools which was originally based on Blast and DOE-2 and has been improved during one decade. However, although it is often used as a benchmark for comparative analysis, its performance is still very sensitive to user inputs. For example, the selection of the rated air flow rate has a significant impact on the DX coil sensible cooling capacity. Within the wide range of rated air flow rate suggested by EnergyPlus, an individual user may select a different rated air flow rate so that the predication could be very different (Hand et. al, 2005). Recently, Yang and Li (2009) developed a GRDB DX coils modeling method. This method was validated by extensive laboratory testing and demonstrated to have good accuracy and to be easy to use. The objective of this paper is to perform an extensive comparative analysis between this GRDB DX cooling coil modeling method and the DX cooling coil modeling method used in EnergyPlus.