Klimaat en behaaglijkheid in monumentale gebouwen

Een historisch (ambachtelijk gebouwd) gebouw wijkt in bouwfysische zin nogal af van wat de hedendaagse aannemer gewend is te bouwen. Muren bestaan bijvoorbeeld uit massief baksteenmetselwerk; vloeren en daken uit een relatief lichte houtconstructie waaraan een stucplafond of een laag pannen of leien is toegevoegd; ramen zijn uitgevoerd als ranke staal- of houtconstructies met een ‘enkele’ (enkelvoudige) geblazen of getrokken plaat glas in elke opening. De gebruikelijke aanpak om te voldoen aan de moderne eisen op gebied van energiebesparing en behaaglijkheid is dat men het oude gebouw zo veel mogelijk wil laten lijken op een modern gebouw. Men brengt isolatie aan, vervangt de ramen door moderne met dubbel (float)glas en voorziet het gebouw van verwarmings- of klimaatinstallaties alsof het een modern gebouw zou zijn. Dat kan ook anders, door aan de hand van een goede bouwfysische analyse op maat maatregelen te treffen. Zo kan het gebouw niet alleen slimmer en beter voldoen aan de gestelde eisen, ook kan veel meer van de bestaande bouwsubstantie (onaangetast) bewaard blijven. Ook om bepaalde schade te begrijpen (en goed te kunnen verhelpen), of juist om bepaalde schade te voorkomen, is een goede bouwfysische analyse vaak onontbeerlijk. Hoe verschaft men zich echter de kennis en informatie die nodig is om op een andere manier, slimmer dan gewoon volgens het staande gebruik, energie te besparen, behaaglijkheid te bevorderen, en schade te voorkomen. Meten is weten, zo luidt een bekende slogan. Wat moet je echter meten om een gebouw qua binnenklimaat te begrijpen? Op hoeveel plekken moet je meten, en wat en waar? En hoe word je wijs uit de enorme rijstebrijberg aan gegevens die je zo ter beschikking krijgt? Hoe kun je daarmee maatregelen bedenken en vooraf ook testen wat het effect van die maatregelen is. Het moderne onderzoek naar klimaat in gebouwen maakt daarbij gebruik van computermodellen van gebouwen. Die modellen zijn gebaseerd op tekeningen en meetgegevens. Zo wordt een model verkregen dat niet alleen het huidige gedrag van een oud gebouw verklaart, maar waarin ook het effect van maatregelen adequaat is te voorspellen. De voordracht licht deze methode toe en laat enkele praktijkvoorbeelden van de toepassing ervan zien

A sound indoor climate for a museum in a monumental building

Museums are often housed in monumental buildings. These buildings were originally not built for this purpose. For the preservation of the artefacts in a museum the indoor climate is often restricted to a very narrow interval for temperature, but most of all for relative humidity. This restricted indoor climate originally dates from the 1970-ties. This indoor climate, however, does not fit well into an old building. The indoor surface conditions near cold walls under winter conditions lead to mould building and other deterioration of the wall surfaces. But principally the museum conditions of artefacts near the cold walls are not in line with museum recommendations. For some typical Dutch museums case studies have been done to show the building physical effects of housing a museum climate in an old building. A number of well known Dutch museum were selected to be examined. The buildings and their HVAC systems were analysed in a methodical way. For at least a year temperature and relative humidity measurements were recorded in different rooms and at different external wall surfaces of the museums. Additionally outdoor climate, CO2, ventilation and infiltration measurements were recorded when needed. The results of this measurement campaign were a large number of indoor climate conditions in different museums in rooms and near external walls. There was a large contrast between the aimed indoor museum climate and the measured resultant indoor climate in rooms and near external walls. The aimed indoor climate in museums which are housed in monumental buildings should be reconsidered. In the Netherlands a multidisciplinary climate network of people involved with the museum climate like conservators, museum-, monumental building- and HVAC consultants and building physicists is formed to formulate new guidelines for the indoor climate in Dutch museums

Optimal setpoint operation of the climate control of a church

The report presents the characteristics of the Walloon Church in Delft (Netherlands) and a description of constraints for the indoor climate, giving criteria for the indoor air temperature and relative humidity with the focus on the preservation of the monumental organ. The setpoint operation of the HVAC system is evaluated by simulation using MatLab, Comsol and Simulink models. The next main model components are presented and combined in a single integrated SimuLink model: 1) a HAMbase Simulink building model for simulating the indoor temperature and relative humidity, 2) a Comsol PDE model for simulating detailed dynamic moisture transport in the monumental wood (organ) and 3) a Simulink controller model. The building model is validated with measurements. The main advantage of the integrated model is that it directly simulates the impact of HVAC control setpoint strategies on the indoor climate and the organ. Two types of control strategies are discussed. The first type is a limited indoor air temperature changing rate. The second type is a limited indoor air relative humidity changing rate. Recommendations from international literature suggest that 1) a changing rate of 2 K/h will preserve the interior of churches and 2) a limited drying rate is important for the conservation of monumental wood. This preliminary study shows that a limitation of indoor air temperature changing rate of 2 K/h can reduce the peak drying rates by a factor 20 and a limitation of the relative humidity changing rate of 2 %/h can reduce the peak drying rates by a factor 50. The second strategy has the disadvantage that the heating time is not constant.ve easy to create EU maps using MatLa

Improving the (museum) indoor climate in a flooded castle

Amerongen Castle, built in de period of 1674-1680, is an acknowledged special national museum with a historic cultural value (Kanjerproject). Next to the monumental value of the building, it has a special collection that exists of for example a ‘Van Meekeren’ cupboard, a valuable atlas called ‘Amsterdam 1724’ and painted portraits of monarchs like Willem de Zwijger. The building and the collection are subject to deterioration. As a result of a flood of the river Nederrijn, the basement was completely flooded with water in 1993 and in 1996. This made the deterioration worse. For a period of approximately a year and a half ICN (The Netherlands Institute for Cultural Heritage) has been measuring the indoor climate in the castle. It appeared that the indoor climate was indeed not favourable for the conservation of the collection. The purpose of the work is to understand the effects of flooding of a monumental building, to understand the impact of visitors and the presence of hygroscopic materials on the indoor climate. Finally the indoor climate of the building should be improved. On the basis of the measurements made by ICN the indoor climate of the different museum rooms was mapped. For the judgement of the indoor climate several techniques have been used, namely the climate evaluation chart, the climate evaluations map and the climate evaluation tables. A simulation model has been used to study the effects of flooding, visitor impact and hygroscopic materials in several museum rooms of Amerongen Castle. Finally the model was used to predict the effects of additional heating. The indoor climate of the building has long been influenced by flooding in the past. Visitors of the mu-seum rooms nowadays influence the indoor climate with their heat and moisture production. Generally, the heat production of persons is normative for the relative humidity in the room compared to the moisture pro-duction. The result is a decrease of the relative humidity in the room and an increase of RH near the cold walls. It appears that the indoor climate also depends for a large part on the furniture of the room. It is sta-bilized by the presence of hygroscopic materials in the room (furniture, carpet, curtains, etc.). The library e.g. has a filled bookcase. The presence of these hygroscopic objects (books) in the library seems to be re-sponsible for the comparatively stable relative humidity, in combination with the use of a mobile dehumidi-fier. Two studied heating systems (humidistatically controlled heating and floor heating) will lead to a more favorable indoor climate. Floor heating will be applied in the basement and the hall and long corridor on the first floor (beletage) and the humidistatically controlled heating system in the remaining museum rooms. The results seem to be promisin

Inverse Modeling of the Indoor Climate using a 2 State 5 Parameter Model in MatLab

This document shows how a simplified dynamic model can be derived from input-output signals. The input signal contains the external air temperature, relative humidity and solar irradiation. The output contains the indoor air temperature and relative humidity. The goal model consists of 2 states and 5 parameters with a physical meaning

The Use of COMSOL in Teaching Heat and Moisture Transport Modeling in Building Constructions

This paper presents the use of the multiphysics package COMSOL for teaching heat and moisture transport modeling in the research area of building physics. It includes a description on how COMSOL works and six exercises with 2D, 3D, steady state and transient models. It is concluded that COMSOL is a very useful tool for this kind of engineering education. Especially, the abstraction level of working with partial differential equations (PDEs) has the advantage that the theory (also based on PDEs) can be relative easily implemented in the models

Effect of Texting with Friends during Video Lectures on High School Students’ Learning

The purpose of this study was to examine high school students’ learning by looking at the effect of texting with friends through a computer chat program on their comprehension and memory of video lectures. Two videos were selected and two settings (texting and no-texting settings) were created. Students were asked to watch one video while being interrupted by a friend to text with them, and to watch another video without being interrupted. The results of the students’ video lecture comprehension and memory quizzes showed that the students scored lower while texting with friends, and that they scored differently between the two videos when texting with friends

An overview of experimental and simulation work on indoor climate and control in historic houses and monumental buildings

In Eindhoven University of Technology a unit of Building Physics and Systems (BPS) is working on topics of building physics and (HVAC) systems. The group has a number of experimental facilities and is working for more than 35 years on the computer simulation of the indoor climate in buildings in general and thermal comfort of people in particular. The group has a lot of contacts with institutes on the preservation of monumental buildings and collections. Therefore a special section is working on the topic of building physics and systems in monuments. This group of people is working on topics of heating, cooling and ventilation in historic houses and buildings, effects of humidification and dehumidification, monitoring and controls, pollution and soiling, the balance between conservation and human comfort and sustainability. The purpose of their work is threefold: getting a better knowledge of building physics and systems in monumental buildings, improving the indoor climate and durability for the buildings and their collections and propagation of this knowledge to students, engineers and architects in practice

Modeling the effect of climate change on the indoor climate

Within the new EU project ‘Climate for Culture’ researchers are investigating climate change impacts on UNESCO World Heritage Sites. Simulation results are expected to give information on the possible impact of climate change on the built cultural heritage and its indoor environment. This paper presents the current and new modeling approaches necessary for obtaining the required simulation results, by: Firstly, providing an overview of the current state of the art on the modeling of historic buildings at several scales using scientific computational software. Secondly, presenting an approach on how to incorporate the effect of climate change into the building models. Thirdly, providing a preliminary method for up-scaling building spatial level models onto a continental level. The latter provides maps that visualize the impact of external climate change on indoor climates of similar buildings spread over Europe