English

This paper demonstrates a systematic approach towards exploring the impact of urban built form and the heat island effect on the levels of domestic energy consumption in London. The study combines GIS databases and a modified version of the Standard Assessment Procedure (SAP) algorithm in order to estimate the space heating demand of urban domestic energy users. The output data is aggregated to the Middle Layer Super Output Area (MLSOA) level.

Mixed-Mode ventilation is an innovative approach that maximizes the use of natural ventilation and uses supplementary mechanical cooling only when strictly required. The application of Mixed-Mode ventilation in severe arid climates and its integration with other passive cooling strategies is very challenging and has not been systematically studied. The paper will present an evaluation of the performance of different Mixed-Mode cooling strategies for a single-zone office space in four main arid cities that represent the diversity in arid climates.

This study analyses vertical temperature profiles for displacement ventilation depending on a ceiling height of an small office room. This study purposes to investigate the influence of the ceiling height on thermal comfort of the occupants. Numerical simulations are carried out for a modeled room which dimensions 5.3m by 5.44m by 2.5m, 3m and 3.5m ceiling height. A finite volume method is used for solving the governing equations and low Reynolds number k-ε model is applied as a turbulent model.

The present study aims to validate several cross and single-sided natural ventilation models implemented in the Building Hygrothermal and Energy Simulation program PowerDomus (Mendes et al., 2003) i.e. the British Standard (1999) model for cross ventilation and the de Gids and Phaff's (1982) and Larsen’s (2006) models for single-sided ventilation. Airflow rates obtained by those models are compared to the measurements performed in two full-scale buildings: one single room house located in a wind tunnel facility and one real three-storey building.

Air quality in aircraft cabins has long been criticized. Current widely-used air distribution systems on airplanes dilute inside generated pollutants by promoting air mixing and thus impose risks of infectious airborne disease transmission. In addition, low moisture content in cabin is believed to be responsible for headache, tiredness and lots of other unknown symptoms.

In order to assess the influence of energy reduction initiatives, to determine the expected annual cost, to calculate life cycle cost, emission impact, etc. it is crucial to be able to assess the energy consumption reasonably accurate.  The present work undertakes a theoretical and empirical study of the uncertainty of energy consumption assessment of domestic buildings. The calculated energy consumption of a number of almost identical domestic buildings in Denmark is compared with the measured energy consumption.

In practise many buildings show significant deviation between the predicted annual energy consumption and the actual energy consumption. One of the main reasons for the discrepancy is the difference between the assumptions made during the calculations and the actual conditions including occupants’ behaviour.  This paper presents two methods to consider uncertainty and spread of energy consumption calculations in practise, namely a simulation approach and a safety factor approach.

Increasing attention is being paid to the application of uncertainty and sensitivity analysis methods to model validation and building simulation. The idea is to let users to apply uncertainty bands to their model input data. These bands are then propagated through the model to determine the uncertainty bands of the simulation results. Mathematical methods to deal with uncertainties in computer simulations are well developed.

In this paper, a sensitivity analysis has been carried out on a set of variables identified during the building conceptual design stage. The sensitivity analysis is performed on a simple intermediate floor of a typical multi-storey office representative of the office building sector for different Italian climatic zones. The conclusions are drawn in terms of sensitivity indexes of energy performance indicators for a set of different design variables and for different climatic zones.

Sensitivity analysis is a key part of a comprehensive energy simulation study.  Monte-Carlo techniques have been successfully applied to many simulation tools. Several sampling techniques have been proposed in the literature; however to date there has been no comparison of their performance for typical building simulation applications. This paper examines the performance of simple random, stratified and Latin Hypercube sampling when applied to a typical building simulation problem.