IJV11

The approval of the Technical Building Code has meant major changes in the construction of multi-storey buildings in Spain. One of the most important revisions, with respect to the buildings erected prior to the Technical Building Code, has been the obligation to ventilate each one of its rooms. Depending on the use and occupancy a minimum flow rate of ventilation is required in each room.

The type and thickness of insulation on the topside horizontal of cold pitched roofs has a significant role in controlling air movement, energy conservation and moisture transfer reduction through the ceiling to the loft (roof void) space. To investigate its importance, a numerical model using a HAM software package on a Matlab platform with a Simulink simulation tool has been developed using insitu measurements of airflows from the dwelling space through the ceiling to the loft of three houses of different configurations and loft space. Considering typical UK roof underlay (i.e.

Natural ventilation in residential dwellings is very important for occupants’ health and comfort. Previous studies by the authors have concluded that natural ventilation performance in dwellings can be enhanced by positioning the two groups of window openings (bedroom windows and living room windows) in opposite directions or perpendicular to each other; and/or the use of side-hung windows. However, the buildings selected for those studies were located in an isolated site, for the purpose of focused evaluation of the influence of various configuration parameters and window types.

It is still difficult to confirm from available data if global warming and climate changes have played a role in increasing heat-related injuries. However, it is certain that global warming can increase the frequency and intensity of heat waves, which can cause discomfort to the human body and, in the worst case, can lead to more heat illness casualties. Recent worldwide natural disasters, such as the Tohoku earthquake in Japan, flooding in Thailand, and the Pakistan heat wave show that climate change is truly a fact.

Air tightness is an important property of building envelopes.  It is a key factor in determining infiltration and related wall-performance properties such as indoor air quality, maintainability and moisture balance.  Air leakage in U.S. houses consumes roughly 1/3 of the HVAC energy but provides most of the ventilation used to control IAQ.  There are several methods for measuring air tightness that may result in different values and sometimes quite different uncertainties.

This paper reports on research carried out to develop natural ventilation control strategies for densely occupied learning spaces with the intention of improving indoor air quality and heating energy consumption. Investigations were carried out for two test cases according to the characteristics given in CIBSE Guide A (2006) and Building Bulletin (BB) 101 (UK Department for Education, 2006). The performance of these test cases were assessed using dynamic thermal simulation with fixed CO2 set-points, based on which opening dampers are controlled.

This paper presents results of a Large Eddy Simulation (LES) of buoyancy-driven natural ventilation in which two unequal heat sources are used to drive the flow. The aim of this work was to assess the performance of LES in modelling turbulent thermal plumes in a naturally ventilated enclosure and to analyse their interaction with each other. The sub-grid scales of the flow have been resolved by using the Smagorinsky sub-grid scale model. It was found that LES results for the interface height agree well with the theoretical predictions of Linden and Kaye (2006).

In many locations mechanical ventilation has been the most widely used principle of ventilation over the last 50 years but the conventional system design must be revised to comply with future energy requirements. This paper examines the options and describes a concept for the design of mechanical ventilation systems with minimal pressure loss and minimal energy use.  This can provide comfort ventilation and avoid overheating through increased ventilation and night cooling.

A double skin façade (DSF) aims at reducing heating and cooling loads by taking advantage of daylight and utilizing heated air for space heating. To take advantage of a DSF a sophisticated design is required. In this paper a DSF building that has overheating problems was selected to verify the causes and propose remedial solutions. The problem was verified by analyzing the measured solar radiation, inside and outside temperature and air velocity. The results of the measurement analysis showed that airflow congestion caused overheating inside the building.

The paper presents the development of a mathematical model and a simulation tool for the transient prediction of the indoor climate and the heat loads in a car cabin, under real operating conditions. The main objectives were to develop a tool which facilitates, for example, the design of a cabin HVAC system or an on-line control. The model is based on the energy balance between the cabin and the outdoor environment accounting for conduction, convection and shortwave and longwave radiation.