Publicaties

Demand controlled ventilation (DCV) refers to a ventilation system with air flow rates that are controlled based on a measurement of an indoor air quality (IAQ) and/or on a thermal comfort parameter. DCV operates at reduced air flow rates during a large amount of the operation time and thus consumes less energy for fan operation and heating/cooling the supply air. The aim of the present research is to assess the IAQ, ventilation efficiency, and ...

Due to its inherent large thermal inertia, concrete core activation (CCA) could assist in active demand response schemes. By shifting the injection or extraction of thermal power in time, demand peaks that normally occur more or less simultaneously in clusters of buildings can be spread out in time. Furthermore, thanks to the low temperature differences allowed with respect to the room temperature, CCA is ideally combined with technologies that ...

A building energy simulation (BES) model of an educational building in Belgium, built according to the Passive House standard and equipped with demand controlled ventilation (DCV), is calibrated using real monitoring data. Measurements of room temperature, fan and heating power are used to calibrate the BES model. This calibration process involves a manual calibration based on an iterative approach. Results show that the simulation results fit ...

This paper presents a numerical model for a compact direct-contact cross-flow air/water heat exchanger where evaporating water cools down an air stream, and where an innovatively designed metallic direct evaporative pad enhances air-water interaction. The numerical model implements energy and mass conservation equations of humid air and water in a one-dimensional geometry by applying correlations for heat and mass transfer coefficients. The ...

Smart windows are used to reduce energy consumption and improve thermal and visual comfort mainly by controlling the solar flux entering into a building. This article presents a simulation study in which the impact of the applied control strategy on the overall energy consumption (heating, cooling and lighting) is investigated. A commercial building located in Montreal (Canada) with south-oriented integrated electrochromic windows is modeled. ...

Model Predictive Control (MPC) is a promising control method to reduce the energy use of buildings. Its commercialization is, however, hampered by the difficulty of obtaining a reliable controller model. This paper compares two approaches to obtain such controller model: (1) a white-box model approach for which a detailed first-principles building model is linearized, and (2) a system identification method using a grey-box model approach. The ...

With reducing energy demand and required installed mechanical system power of modern residences, alternate heat pump system configurations with a possible increased economic viability emerge. Against this background, this paper presents a numerically examined energy feasibility study of a solar driven heat pump system for a low energy residence in a moderate climate, where a covered flat plate solar collector served as the sole low temperature ...

Demand controlled ventilation (DCV) can reduce the energy use significantly compared to a constant air volume (CAV) system. However, there is still uncertainty about the indoor air quality (IAQ) and the ventilation effectiveness of the room. Aim of this paper is to assess the IAQ, ventilation effectiveness, local thermal comfort and energy efficiency of a DCV system in a school building. Measurements of CO2 concentrations and power consumption ...

The quest towards low-energy buildings renews interest in Concrete Core Activation (CCA), because its low heating and high cooling temperatures harmonize with low-exergy production systems. However, CCA is characterized by a large thermal capacity and thus large time constant, which hampers adequate control. Model based control strategies can overcome this challenge if accurate CCA thermal models are available. But, computation time reduction in ...