control

This paper presents the development of a simulation tool based on the Matlab computational environment for building temperature performance analysis with automatic control. The simulation tool contains mathematical models for buildings, HVAC (Heating, Ventilation and Air Conditioning) systems, sensors, weather data and control algorithms. The building mathematical model is described in terms of statespace variables, with a lumped approach for the room air governing equations energy and mass balances. In this context, the simulation tool structure and components are explained.

This paper describes a performance-based evolution model using Genetic Algorith as the evolution algorithm and CFD as the evaluation mechanism. The advantages of such an evolutionary performance-based design approach is that diverse instances of the state space can be investigated in relation to specific goal requirements that will enhance the possibility of discovering a variety of potential solutions. The model allows the user to explore and visualize the design evolution and its form generation in an attempt to stimulate the designer creativity that might contribute to their output.

This paper describes a fault detection method developed for application to variable-air-volume (VAV) boxes. VPACC (VAV Box Performance Assessment Control Charts) is a fault detection tool that uses a small number of control charts to assess the performance of VAV boxes. The underlying
approach, while developed for a specific type of equipment and control sequence, is general in nature and can be adapted to other types of VAV boxes. VPACC has been tested using emulation,

To obtain stable control of VAV systems, many considerations must be accommodated properly. Local and central control loops affect each other in ways that in many cases can lead to problems of poor control and even instability. In a VAV system (utilizing demand controlled ventilation), the stability of the supply air temperature must be very carefully commissioned. While stable control can be obtained more easily at full flow rates, instability can often become a problem during reduced flow rates.

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.

The aim of that study was to develop a fuzzy controller for naturally ventilated buildings. This paper describes the process of designing a supervisory control to provide thermal comfort and adequate air distribution inside a single-sided naturally ventilated test room.

Variable Air Volume system use VAV boxes that serve open areas for five or more occupants, each zone is controlled with a single space temperature sensor. But VAV zone control strategies remained the same for the last years, so the designers have to consider that system : it provides a high quality environment for occupants, it permits the use of a smaller air-distribution system that is low cost and does not compromise building comfort or operating efficiency.