Embedded water-based surface heating part 2: experimental validation

The transient operation of an embedded water based floor heating system has been studied by means of a numerical simulation tool. Prior to this study, Caccavelli et al. (1994) experimentally derived reference data for the specific setup. This paper constitutes an attempt to experimentally validate the numerical simulation tool that was recently developed by Karlsson (2010). The thermal response of the system is tested in both long (16 h) and short (30 min) cycle experiments where the water flow alter between on and off. Temperature distribution, within the floor construction, and the heat exchange process are studied throughout the test cycles. The model underestimates the steady state heat exchange from the pipe loop by 16% when boundary conditions and thermal properties according to the reference case are applied. Temperatures at the floor surface are assed with good precision while temperatures at the core of the concrete slab are underestimated by up to 1.5°C. Amplitudes, phase shifts, rise and delay times at different measurement points are simulated with good precision. A sensitivity analysis is performed where material parameters and boundary conditions are analysed. None of the tested parameters can independently explain the observed general trend in temperature deviations between simulations and measurements

A BIM based decision support system for building maintenance

Available data about asset condition and performances can be conveyed into different Key Performance Indicators (KPIs). Many KPIs measuring technical, functional and economic/financial asset performances can be found in literature. Nevertheless, they are often strictly related to a specific scope, thus they provide an incomplete depiction of the whole assets performances. The objective of this research is to provide facility managers and asset owners with an easy instrument to prioritize maintenance. In order to reduce costs related to its use, the instrument, developed in the form of a Decision Support System (DSS), is based on existing and reliable performances metrics and leverages new technologies like Building Information Modelling (BIM). Accordingly, the Facility Condition Index (FCI) is combined with the D index, a KPI related to the age of building components, developed by the authors. The joint use of the FCI and the D index, allows facility managers to make more conscious decisions. The proposed DSS helps in the definition of the best maintenance plan, providing a ranking of building components which require more urgent maintenance interventions. Although the DSS should be tested measuring its ability to preserve buildings and their performances on a long term, the first results are positive, as confirmed by the application to a case study on an office building in Italy. Moreover, the usability of the instrument has been appreciated by the users in a medium size Italian company

A new approach to provide sustainable solutions for residential sector

An energy-efficient appliance normally presents a lower energy con-sumption compared to a less efficient one, with a higher initial investment, alt-hough this not always happens. Additionally, each appliance, presents very dif-ferent features, leading to some difficulties on its choice by the consumer (deci-sion-agent). On the other hand, each consumer, has specific and distinguished needs from other consumers, namely of social, economic or environmental nature. Even by adopting these criteria, this is not an isolated guarantee of an optimal solution for the consumer. It is then necessary to complement this approach with multicriteria, combined with optimization techniques. Evolutionary Algorithms (EA), could be used as an optimization technique, to provide sustainable solutions to the consumer, from the market. In this paper, it’s presented an approach that integrates both concepts, where at the end, it shall be presented a case study, to demonstrate the application of the proposed method.info:eu-repo/semantics/publishedVersio