IBPSA2011

One of the big challenges in comparing measured and simulated energy performance of buildings is that most energy models do not capture the significant impact of installation, operational and degradation HVAC system faults on actual energy performance in buildings. EnergyPlus, a comprehensive whole building performance simulation tool, also has limited capability of modeling HVAC faults. The research described in this paper identifies, characterizes and prioritizes common faults of HVAC equipment and control systems, some of which are incorporated in EnergyPlus.

The work presented in this paper aims to compare two different climates in Australia and Reunion Island and to identify the similarities in terms of bioclimatic design of low energy building.

Guidelines for the safe design of semi-open car parks require a minimum amount of open façade in order to ensure an effective removal of heat and smoke during a car fire. In this study the fire safety level is assessed by the use of validated Computational Fluid Dynamics (CFD) simulations of different design variants. The fire safety is assessed using temperature and sight length criteria for safe deployment of the fire department. Results show that 3 out of 7 studied variants did not meet these criteria.

Because of their low cost, small air conditioning, systems are often installed without any study on building envelope performance and without strictly complying with the rules of art. This article presents a pragmatic and global approach to diagnose performances of air-conditioned building relying on a numerical tool and dynamic simulations of buildings coupled with HVAC systems. Simulations calculate the required cooling power and evaluate the impact of the implementation and of maintenance.

In this paper, analysis is performed on the uncer-tainty in energy consumption calculated from whole-building energy models of two different building de-signs; a typical code compliant building, and the same building redesigned with high performance elements. We perform sensitivity analysis which reveals which parameters (out of approximately 900) influence the uncertainty in the consumption of energy in the build-ing model the most. We conclude that the most sensi-tive parameters of the model relate to building opera-tion (i.e.

The aim of thise paper is to take the advantage of CFD application in calculating, optimising, and designing air curtains used to separate smoke free zones in case of fire. Properly designed air curtain produces a pressure drop which forbids transversal flow through the opening. Most air curtains are tested on scaled down models which are difficult to extrapolate. The intention of this paper is to present the possibilities of CFD while designing air curtains used in fire safety engineering. 

Standardized building performance assessment is best expressed with a so-called normative calculation method, such as the CEN/ISO calculation standards. The normative calculation method has advantages of simplicity, transparency, robustness, and reproducibility. For systematic energy performance assessment at various scales, i.e., at the unit of analysis of one building up to a large-scale collection of buildings, the authors’ group developed the Energy Performance Standard Calculation Toolkit (EPSCT).

The paper aims to evaluate the thermal performance of a typical Chinese low-energy residential building in ‘Hot Summer and Cold Winter’ zone where two prototypes within a six-storey healthy housing with low-energy standards have been investigated. According to the building simulation study undertaken, prototype 1 has relatively good thermal performance compared to prototype 2.

This study investigates in detail conventional and advanced shading devices. Thermal and visual aspects are considered as well as advanced control strategies. The systems are compared regarding energy balances, daylight provision and visual comfort aspects (glare, view contact).  Outside mounted systems offer in all investigated cases best solar protection. A combination of external shading and internal glare protection can reduce the overall energy demand by more than 25% compared to a solar control glazing and/or only internal mounted shadings.

Assuming that isolating a building might not be the best solution to exploit the free renewable sources of its environment (outside air temperature, sky temperature, solar radiation…), a first identification step has been carried out to determine which sources should be exploited. Building energy simulations have been carried out, including various isolation levels and climatic conditions. Then, indicators have been defined in order to quantify the ability of the previous sources to cover the energy needs and the possibility for the building to exploit them.