Methodology for the Evaluation of Natural Ventilation in ... - Cham

Chapter 7.0Experimental ResultsExperiments were carried out on the reduced-scale air model described in Chapter 6. The resultsof those experiments are presented here, categorized by the type of ventilation: buoyancy-driven,wind-driven and combined buoyancy-wind driven flows. The airflow rates and temperaturedistributions are used to assess the ventilation scheme and then compare the reduced-scale airmodel to the prototype building that was monitored. The temperature data are presented aspredicted temperatures for a full-scale building, using the dimensionless methods presented inChapter 5. The data recorded using the reduced scale model require the use of the referencetemperatures to scale the recorded data for use in predicting full-scale building temperaturedistributions. This was completed using the reference temperature equation presented in Chapter5. The reference temperature was based on the heat flux, W/m 2 , the properties of the workingfluid used, and the height of the model.For the single zone case (a), there was only one heated zone with two heaters that had ameasured output of 500 watts. The two heated zone case (b) had twice the number of heatersand therefore twice the amount of heat at 1,000 watts. The full model experiments (c) had a totalof 2,000 watts of heat input. Diagrams for each of the configurations with the heaters are shownin Figure 44 a, b, and c. The reference temperatures were calculated using equation 7.1. Theresulting reference temperature differences are provided in Table 27.132 Q ATref2(7.1)cp gHIf the model accurately simulates the building, then:T T TT (7.2)Tref TM ref PTrefP TP T(7.3)T MrefM117