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a b s t r a c tA matched pair of 1930s semi-detached houses, in original condition and un-refurbished in terms of energy efficiency, were employed to measure the energy savings that might result from the use of zonal space heating control (ZC). The houses were adjoined and had the same synthetic, yet realistic, occupancy schedule, the same new central heating system, and were exposed to the same weather conditions. In one house the space heating was controlled conventionally (CC) according to minimum requirements in UK Building Regulation Part L1B for existing dwellings, whereas in the other house ZC was used to heat the rooms only when they were 'occupied'. Over an 8-week winter test period, the house with ZC used 11.8% less gas despite 2.4 percentage points drop in average daily boiler efficiency. Although zonal control reduced the mean indoor air temperature of the whole house by 0.6 • C, it did not reduce the average air temperature in rooms during the hours of active 'occupancy'. Normalisation and extrapolation of the results shows that, compared to CC, ZC could reduce annual gas demand for space heating by 12% in most regions of the UK, and that ZC would be a more effective energy efficiency measure in homes in the cooler, more northerly regions of the UK.

This paper presents a new approach, in applying the Pierce two-node model, to predict local skin temperatures of individual body parts with good accuracy. In this study, local skin temperature measurements at 24 sites on the bodies of 11 human subjects were carried out in a controlled environment under three different indoor conditions (i.e. neutral, warm and cold). The neutral condition measurements were used to adjust the local skin set-points in the model for each body part. Additional modifications to the calculation algorithm were introduced corresponding to different body parts. The local core set-points were then calculated, using a line search method, as the input values that allow the model to predict the skin temperatures with maximum deviation of ±0.1°C for the neutral condition. The model predictability was verified for the other two indoor conditions, and the results show that the modified model predicts local skin temperatures with average deviation of ±0.3°C.

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This study introduces a new Air Distribution Index (ADI) New to assess the ventilation performance in uniform and nonuniform thermal environments. The index comprises parameters for assessing the indoor thermal comfort and air quality in occupied spaces. The thermal comfort assessment was carried out using a virtual thermal manikin that is adjusted by a model of human thermoregulation and coupled with a psychological comfort model. The virtual manikin was used in a computational fluid dynamics (CFD) code to simulate tests in an environmental chamber that were largely conducted under thermally neutral conditions with mixing ventilation (MV) or displacement ventilation (DV) systems. Eight human subjects were used in the study that included measurement of their skin temperature, local and overall thermal sensation votes during their exposure to the MV and DV systems. The results from CFD predictions were compared with measurements in the test chamber. The predicted (ADI) New parameters, such as the thermal comfort, the ventilation effectiveness for both heat and contaminant removals as well as the local mean age of air, were compared with measured values in the chamber and found to be in good agreement. The results demonstrate that (ADI) New is a useful index for evaluating the performance of a ventilation system under uniform thermal environment and can also be applied to nonuniform environment.