English

The numerical evaluation of room air movement is made by systematic discretization of space and the dependent variables. This makes possible to replace the governing differential equations with simple algebraic equation. The dynamic model of the temperature is based on the energy balance equation, considering a given flow field. The temperature in a given control volume depends on the temperatures of its corresponding neighbours. This form of the model is. not appropriate for control theory.

The performance of a glazed solar chimney for heat recovery in naturally-ventilated buildings was investigated using the CFD technique. The CFO program was validated against experimental data from the literature and good agreement between the prediction and measurement was achieved. The predicted ventilation rate increased with the chimney wall temperature. The effects of solar heat gain and glazing type were investigated. It was shown that in order to maximise the ventilation rate in a cold winter, double or even triple glazing should be used.

This paper describes the measured and calculated results of airflow rates and pollutant concentration profiles in an airtight test house, the aim being to evaluate the calculation model COMIS for multizone air infiltration and pollutant transport. Firstly, the leakage areas of internal doors, exterior walls and windows were measured by the fan pressurization method. Secondly, two measurements were carried out, assuming that the test house consisted of ten zones.

A two-dimensional turbulence k-e model is used to predict distribution of air velocity, temperature and turbulence kinetic energy in an air-conditioned room using ceiling air supply. Mixing characteristics of the airflow are analyzed under different air supply velocities and temperatures. A modified Archimedes number is correlated with the parameter ·characterizing heat transfer, ventilation system, and turbulence kinetic energy of room air flow. Significant correlations have been shown.

An experimental setup is presented that can measure concentrations generated around a pulsating source of carbon dioxide (C02) that simulates human respiration. The experimental setup is used to study the relationship between the ventilation efficiency and the pollutant removal efficiency of a space. These are two key parameters which describe the ability of a space in providing a comfortable and healthy environment for its occupants. Preliminary results obtained so far have focused on the conditions inside a small test chamber.

A house without a heating system in our cold climate - is it possible? In each of Goteborg, Malmo and possibly also in Hannover, about 20 terrace houses which are so energy efficient that they need no special system for heating are under construction. The Swedish Council for Building Research (BFR) is providing financial assistance.

The steepest descent and simulated annealing optimization techniques are used to simultaneously estimate the effective mixing volumes and air exchange rates of a large partition less building exhibiting heterogeneous spatial air flow conditions. The optimization is conducted using varying quantities and qualities of simulated tracer gas measurements. A simulated three-compartment system is numerically investigated to assess the performance of the parameter estimation methods.

The Interactive Window hair System was a sterling effort by Colt International, aimed at developing an integrated and modular product for use in naturally ventilated buildings. Milton Park Ltd piloted the system in a passive solar building completed for Marston Book Services. How well has the building performed?

The performance of a heat-pipe heat recovery unit was tested in a two-zone chamber with a horizontal partition. Air velocity was found to have a significant effect on the effectiveness of heat recovery. The effectiveness decreased with increasing air velocity. Simulation of air flow was carried out for the test chamber under natural ventilation conditions. It was shown that a heat-pipe heat exchanger can be used to reclaim exhaust heat in naturally ventilated buildings to effect energy conservation.