ventilation

This paper provides a summary of the methods and results of performance testing for a coupled Indoor/Outdoor Environmental Simulator (C-I/O-ES). The simulator consists of an IEQ chamber, a climate chamber, and a replaceable separation/test wall assembly. Both chambers have stainless steel interior surfaces and are equipped with independent heating, ventilating, and air-conditioning (HVAC) systems for simulating indoor and outdoor thermal and air quality conditions, respectively.

The authors have proposed a system for stabilizing air temperature using direct heat exchange between granulated phase change materials (PCM) and air. This paper describes experiments in which air whose temperature is periodically changed to simulate changes of outdoor air temperature is passed through a bed of granulated PCM. These experiments demonstrate that output air temperature is stabilized and remains within the phase change temperature range. Results calculated by a computer simulation program described in a previous paper duplicate the experimental results.

The CEN TC 156 / WG2 (ventilation for residential buildings) has prepared a new European draft for the test method of Heat Recovery Units (prEN 13141-7). This method should ensure a common way of testing these units all over Europe. In order to determine if the draft procedure is sufficient enough, both VTT and CETIAT has proceeded to some tests according to the new European standard on the same unit. Results on this first intercomparison give interesting data on the test method applied.

Even in cold climates, offices normally need to be cooled due to the internal heat loads from people, equipment and lighting. Either a chilled ceiling or chilled beams with cooled water as medium or chilled air can be used. In the case with chilled ceiling or chilled beams, a constant air volume system (CAV) is used. In the case of air only, a variable air volume (VAV) system must be used. This paper presents the advantages of the two methods of cooling with respect to energy use, which was calculated from climate data.

The paper describes a system solution developed in Sweden for domestic buildings with pre-cast concrete units where the floor consists of a 0,06 meter thick concrete slab with a framework casted into the slab and a beam. The beams acts as floor beams forming a cavity of about 0,3 meter that are used for plumbing, electric installations and transport of air for heating and ventilation. The air is blown from the cavity into the rooms through narrow slots along the walls. Air for heating is recirculated through a ventilation plant consisting of filter, heating element and a fan.

Every city or town has a market to supply fresh food to its residents. A market has the function of displaying fresh food, auctioning it, and supplying it to consumers. A market must fulfill this role throughout the year even in cold, snowy areas, and this calls for a large, covered space. At the same time, vehicles of various sizes drive in and out of the market premises to transport food into and out of the market. These vehicles emit exhaust gas, however, and the introduction of a large amount of fresh air into the market space is indispensable for maintaining good air quality.

Theoretically if the thermal properties of a building envelope and the power of the HVAC systems are known, then air infiltration becomes the only one unknown component of the thermal balance of a building and could be defined from it. In reality, all data are approximate. Modern measurements and data processing techniques allow one to evade this obstacle.

The new perspective technology in building heat supply and climatisation, are given in this paper. The main energy-saving solutions are following: architectural and layout design taking into account the influence of solar radiation and wind direction; high thermal insulation of building envelope and glazing; mechanical supply-and-exhaust ventilation systems for each flat; Ground heat and exhaust air heat recovery for hot water supply; doublepipe heating system for each flat, horizontal, equipped with flat heat meters and thermostatic valves installed at each room heater.

Historically, industrial buildings have been simple constructions with no insulation. Ventilation has been natural through openings in the walls and in the roof. Around 1970 we started investigating airflows in large industrial premises by water model studies. This lead to a better understanding of the ventilation airflow patterns in heavy industries. In the following years, the principles were applied in practice. At the present, more than 30 large plants have been designed according to these principles and valuable experience has been gained.

An evaluation of different ventilation principles and their application in various premises like bars and restaurants has been conducted. Measurements of nicotine concentrations revealed a strong dependency on ventilation solutions. In restaurants and bars where the ventilation systems are properly designed it is possible to fulfill requirements issued by the Norwegian authorities.