Submitted by Maria.Kapsalaki on Tue, 06/17/2014 - 17:11
In order to solve the unbalance problem and increase the system efficiency of central heating, a new-style adjusting model in the building internal system —onoff valve adjusting system which is composed of by the on-off valve 、controller、 indoor temperature sensor is put forward.
Submitted by Maria.Kapsalaki on Tue, 06/17/2014 - 14:51
In this paper, we present a heating system with thermal storage using a heat pump which supplies heat to the thermal storage equipment installed in the crawl space of residential house insulated at the foundation walls. This system can charge heat by using cheap nighttime electricity and discharge the stored heat at daytime.
During the design process of heating systems, the designer must analyse various factors in order to determine the best design options. Therefore, the environmental aspects of a product should be included in the analysis and selection of design options if an environmentally - aware design is to be produced. If one wishes to assess a products environmental impact, its whole life cycle must be studied. The Life Cycle Assessment (or LCA) methodology is an example of one kind of environmental analysis which included the entire life-cycle of a product. However, this method has some limitations.
Within the European project - Friendly Heating - a local heating system is designed. The main goal is not to heat the monumental churches themselves, in order to prevent damage to valuable art works and the building itself. The idea is to provide a thermal comfort zone for the people in the pew using radiant heat sources. Measurements in a climate room are used to a) evaluate the local climate created by the bench heating system and b) evaluate the CFD model. The results will be used in ongoing research on the prediction of the indoor climate in a church under real climate conditions.
Achievement of thermal comfort can be improved if individual control of the environment is allowed,namely through a local heating system (LHS), consisting of individually controlled radiant heating panels, adapted to a common office desk to a seated person. The coupling with of a new radiative module enhances the simulating capabilities of an existing CFD numerical model. The added improvements are applied to the evaluation of the thermal performance o the LHS. A comparative analysis clearly demonstrates the relevance of a due consideration of radiative exchanges.
The Sint-Pieterschurch in the city of Ghent is one of the largest churches of the city. It was built in the 17th century. The city council wants to use the church not only for its religious functions, but also for cultural activities as concerts and exhibitions. To be able to do this the thermal comfort of the visitors has to be guaranteed. At this moment the church has no central heating system. Gas heaters are used during services. Installing a central heating system will influence the humidity and moisture behaviour of the church.
The objective of the annex 34 was to develop HVAC fault detection and diagnosis tools, which are closed to commercial products. The approach was to design a number of different computer based demonstration systems that could be interfaced to HVAC processes in buildings. By monitoring the operation of these demonstration systems, researchers were able to test a variety of fault detection and diagnosis methods and technique in a real environment, find possible shortcomings and obtain new ideas for further development.
In this paper the author analyses the different weaknesses of the HVAC systems in case of air contamination by a deliberate pollution of the inducted air due to vandalism, terrorism or any other motives.To prevent that danger he gives some advice about HVAC installation :A safe air intake is necessary, but the intake grille for ventilation must be inaccessible from outside the building and its position at ground level unsuitable.Air dampers must have effective sealing and be closed in the event of a bioterrorist attack.Recirculation systems can be contamined too from a source within the bui
Dynamic simulation calculations were operated using TRNSYS software applied to a low energy house. This article is the second one of a serie of two. The first one was dealing with ventilation. This one mainly concerns heating system and domestic hot water production through a gas boiler. It also gives general conclusions, some of them dealing with ventilation.
This report describes the characteristics of a thermodynamic concept, exergy, in association with building heating and cooling systems. It introduces the various forms of exergy and the mathematical formulations used to evaluate them. It gives an example of exergy calculation for space heating systems.