Sökning: "ventilation ducts"
Visar resultat 1 - 5 av 9 avhandlingar innehållade orden ventilation ducts.
1. Ventilation and window opening in schools, Experiments and Analysis
Sammanfattning : The objective of this thesis is to study the application of ventilation in schools buildings. A number of studies of the application of different forms of ventilation are presented. The main part of the thesis focuses on window opening in a classroom. Analytical models for calculation of the air change caused by window airing are proposed. LÄS MER
2. Active Noise Control in Ventilation Systems : Practical Implementation Aspects
Sammanfattning : In many kinds of buildings, the ventilation is handled by a mechanical ventilation system. Such ventilation systems constitute a well known source of broadband noise. LÄS MER
3. Laboratory Ventilation Systems: An Analysis of the Function and Flow Stability of Different Ductwork Design Alternatives
Sammanfattning : One of the prerequisites for high safety in laboratories for chemical and microbiological research is a well-functioning ventilation system. The most typical safety measure in these laboratories is to use a fume hood as a place for activities that can cause dangerous emissions to the room air. LÄS MER
4. Active Control of Noise in Ventilation Systems : Analysis and Experiments
Sammanfattning : In many kinds of buildings, the ventilation system constitute a well known source of broadband noise. Traditionally, duct born noise is attenuated using passive resistive silencers which produce a high level of attenuation over a broad frequency range. However, they tend to become large and bulky if designed for low frequency attenuation. LÄS MER
5. Optimal damping and slow sound in ducts
Sammanfattning : The thesis is dedicated to expanding knowledge on two duct acoustic issues including: 1) the optimal damping of low frequency sound and 2) the development and application of ‘slow sound’.To address the first issue, the ‘Cremer impedance’ proposed more than half a century ago has been revisited and further developed. LÄS MER