Pekka Tuomaala

VTT Technical Research Centre of Finland | vtt · Building Services and Indoor Environment

New solutions sometimes face challenges in acceptance as improvements and active citizen engagement plays a key role of resilient smart city development. This paper describes a set of actions in Helsinki as part of mySMARTLife project that are aimed to engage citizens in interaction. The actions range from online services and mobile applications to...

The EVICURES project developed a new user-friendly design model for intensive and intermediate care facilities. In this model staff, management, patients and their families, and corporate, hospital district and other co-operation partners jointly participated in the design work from day one. EVICURES is the first project to study evidence-based de...

Retrofitting of external walls and building façades of residential buildings is often considered as the most energy efficient renovation measure. This paper presents a webbased tool for remote monitoring of energetical performance of a multifunctional façade system for apartment building retrofitting, the "MeeFS" system (www.meefsretrofitting.eu/)....

In northern regions, society can be seriously interrupted by a prolonged electricity network blackout due to a winter storm that cuts off power, communication and road networks. Due to hard winter weather it is essential to enhance the resilience of society to avoid danger to life. This can be achieved by developing new models to enhance preparedne...

There are clear statistical facts indicating importance of evaluating individual thermal sensation in a more detailed manner in the future. The first such fact is apparent: all humans have more or less individual body composition and different tissue type (e.g., bone, muscle, fat, and skin) amounts and distributions. The second relevant fact is tha...

http://www.crismaproject.eu/deliverables/CRISMA_D432_public_print.pdf

Extreme winter storms in northern regions bring heavy snowfall, strong winds and cold weather. Winter storms accumulate snow on power lines, causing damage, power outages and communication breakdowns. They may disrupt society’s normal interactions, especially in sparsely populated areas, due to snow-blocked roads, isolating people and preventing re...

In this paper, we describe the application of two experimental methods on the determination of the heat release rate during the combustion of wood in stoves. The experimental methods are the oxygen consumption method and the carbon dioxide generation method and are adopted from the field of fire safety science. After outlining the basic ideas, we s...

This paper, based on research conducted under the EU FP7 “SuPerBuildings” project, presents current practice and approaches to comfort assessment and specification. The paper compares and discusses the results of different methods used for the calculation of thermal comfort: Fanger's PMV method, the adaptive predicted mean vote (aPMV) method, a Hum...

A new Human Thermal Model (HTM) has been developed at VTT Technical Research Centre of Finland (VTT) for predicting thermal behaviour of the human body. HTM is based on true anatomy and physiology of the human body, and it estimates human body tissue and skin temperature levels. HTM divides the body into sixteen different body parts each being furt...

This paper describes the basic features of a new advanced human thermal model (HTM), which is integrated with a building simulation tool. The thermal sensation calculation of the model has been validated using dynamical temperature step change test results. This new methodology seems promising, and significance of both internal (metabolic rate and...

Energy-efficiency seems to be one key-driver for whole building and construction industry in the future. Therefore, new construction and building service concepts are obviously needed. Most likely better thermal insulation levels and at least partly new heating and cooling solutions will be adopted. To avoid unpleasant indoor environment outcomes i...

The built environment is a significant part of our national wealth. The built environment is the physical environment created by people. It consists of the buildings and all networks serving the flow of traffic, energy, water, waste and digital information, and the assemblies, equipment and (built) natural elements connected to them. This publicati...

In this paper, the use of an uneven nodal network in floor heating simulation with finite difference heat balance method is examined. Two floor heating test cases, homogenous and multilayer floor, are presented. Temperature distributions on the floor surface and heat flows through the floor surface are simulated with even and uneven gridding approa...

The goal of the work was to fi nd out the best performance of a closed wet cooling tower system combined with chilled ceiling, serving a residential building. The research method was building simulation combined with optimisation. IDA-ICE was used for simulation together with GenOpt optimisation package. A closed wet cooling tower connected to chil...

This paper presents a concept for more realistic and reliable evaluation of thermal indoor environment. A detailed thermal model of a human body, interacting with building simulation model, makes it possible to predict transient tissue temperatures of a human body as well as local skin temperature levels in realistic working and living conditions....

The basic idea of a distributed simulation environment has been presented and elaborated in a new context, in which building energy simulators and district heating network simulator are hydraulically and thermally linked from the power plant via the district heating network to the internal room conditions in buildings. The models and software emplo...

A simplified method to describe the dynamical heat output from heat storing stoves for small houses with a single or several successive firing batches is presented. Both measurements in a stove and theoretical and experimental studies of the combustion of single wood logs can be applied to study the heat input from the batch firing to the furnace w...

Environmental, epidemiological and economical reasons increase the pressure to design, construct and maintain better buildings in the future. Therefore, a new assembly of simulation routines for predicting both ventilation and heat transfer processes of buildings were studied. The work was limited to implementation and evaluation of new air flow an...

Several organizations and expert groups have released different test cases for the validation of building simulation tools. This study is a summary of validation results obtained by a new whole building simulation tool developed at a Finnish national research organization. Currently, this new simulation tool is focused on heat transfer and airflow...

In this paper, the thermal response of a homogenous slab to both step and sinusoidal excitations of temperature at one boundary is examined. The distribution of nodes for the purposes of heat balance thermal modelling is discussed. Errors in the heat flux at the external boundary are examined when even and uneven gridding approaches are applied. A...

A new approach is described for the calculation of radiative heat transfer within buildings. The progressive refinement method together and a fast view factor estimation algorithm are introduced, implemented and tested. Results obtained by the Improved Progressive Refinement Method (IPRM) are compared with the results from the standard matrix metho...

Simulation of air infiltration and ventilation, and heat transfer processes of buildings are combined in a building simulation program called BUS (version 3.2). The program applies and includes an effective sparse matrix solution method for a linear set of equations. A network assumption is adopted for both air flow and thermal simulation. An itera...

We studied the relation between the amount of textile and other soft fiber wall materials used in the office and the symptoms related to sick building syndrome in two identical, mechanically ventilated, eight-story office buildings. The study population consisted of 400 workers (85% of the source population): 264 males (66%) and 136 females (34%)....

This study tested the hypothesis that recirculated air in mechanically ventilated buildings causes symptoms commonly referred to as the sick building syndrome and perceptions of poor indoor air quality. A blinded, four-period crossover trial was carried out in two identical buildings, contrasting 70% return air (index phase) with 0% of return air (...

A new method for modelling multi-zone air infiltration and ventilation simulation and a simple test case are described. The network approach was used, and the solution was based on a fully implicit formulation of the flow equations. In the present version of the building simulation model (BUS version 2.1), the thermal behaviour of a building is neg...

The computer programs published so far have enabled the calculation of airflows at constant temperatures or of air temperatures at constant airflows. The first version of a new microcomputer program has now been developed in which the airflows and temperatures are calculated simultaneously. The time-dependency of temperatures, airflows and contamin...

The computer program for calculating the spread of contaminants in the multi-zone buildings is addressed. The theoretical foundation for the calculating method is presented. Air temperatures in the building zones, interzonal airflows and contaminant concentrations are all interdependent and change dynamically with time. The values of these function...

Energy-efficiency seems to be one key-driver for whole building and construction industry in the future. Therefore, new construction and building service concepts are obviously needed. Most likely better thermal insulation levels and at least partly new heating and cooling solutions will be adopted. To avoid unpleasant indoor environment outcomes i...

A new generation building simulation tool combines the most important inter-acting physical processes (air infiltration and ventilation, heat transfer, and indoor air quality) in an reliable, effective, and flexible way. Here, reliability has been ensured by adopting solution routines based on the fundamental physical laws: mass balance, momentum,...

Thermal comfort standards determine indoor conditions in buildings as well as the energy consumption for heating and cooling purposes. Existing thermal comfort standards are based on steady-state thermal conditions, and according to recent research these standards can not describe thermal comfort accurately enough with transient boundary conditions...

Improving Construction and Use through Integrated Design Solutions. First International Conference on CIB IDS 2009. Belloni, Kaisa; Kojima, Jun; Pinto Seppä, Isabel (eds.) VTT Symposium 259, 253 - 267 Quite wide global consensus seems to be achieved in a desire to improve energy-efficiency of both new and existing buildings when fulfilling internat...

In: Energy Visions 2050, 51-141

In: Huovila, P., Karvonen, A. & Raasakka, V. (eds.) . SB10 Finland, Sustainable Community - building SMART. Conference Proceedings. Espoo September 22-24, 2010, 66-67

SB10 Finland: Sustainable Community - buildingSMART, 74-75 (2-page abstract) New heating and cooling system design data is needed for utilization of renewable low-temperature heating and high-temperature cooling energy in very-low energy houses. This design data must also ensure the overall thermal comfort of the building user. There is a need for...