TABLE OF CONTENTS - The Professional Green Building Council

Theme B: Creating a livable, healthy and environmentally viable citiesξ240.87 0.52uca16.99cm/s 15.04cm/sComparing Systems 1 and 2, System 1 had a higher cavity airflow velocity as wellas greater temperature differences except hca,4. For these reasons, System 1 for Step5 had higher convective thermal transfer coefficients as in Step 4. ComparingTables 6 and 8, it is shown that the convective thermal transfer coefficients in Step5 are higher than those in Step 4. This is because convective thermal transfer hasincreased due to airflow movement within the cavity in Step 5. Table 9 showscomparison of the estimated convective heat transfer coefficients with the literaturevalues. Significant discrepancies exist between the estimated and reference valuesfor Step 5 for similar reasons explained in Step 4.Table 9: Comparison of the estimated values with literature values with the cavity openSystem 1 System 2estimate literatur estimate literatur literaturd e d e evalues values values valueshca ,27.03 1.6 6.47 1.65 [5]hca ,39.5 1.43 3.99 1.51 [5]hca ,47.23 2.47 5.62 4.37 [5]7. VALIDATIONValidation processes were conducted performed to check whether the calibratedmodel is capable of accurately predicting the system’s response. Park et al [8]explain the validation process for System 1, thus the process for System 2 is onlyprovided here. For the purpose of validation, an experiment was conducted forabout 127 hours (Aug 25, 2007 - Aug 30, 2007) with a sampling time of 1 minute.The weather varied significantly from clear to rainy during the experiment. Duringthe experiment, the louver slat angles and the airflow regimes were “randomly”changed and these changes were logged and reproduced exactly in the calculation.513