Experimentelle und theoretische Untersuchungen zum Schalldurchgangdurch Einfach- und Doppelplatten in Luft und Helium bel Drücken bis 50 bar

摘要

The thermal insulation in hot gas ducts of High Temperature Reactors (HTR) is subjected to dynamic loads due to pressure fluctuations. These fluctuations which are caused by turbomachines or by turbulent pipe flow may cause mechanical failures. To find out the transmission of sound energy through the structure of the insulation it is necessary to make investigations at pressures up to 50 bars with helium. The first part of this report deals with the radiation of sound by blowers and the propagation of sound in circular tubes. As an approximation to on insulation the transmission of sound through single and a double plate is calculated. Bases of the calculations are kown methods of room acoustics and Statistical Energy Analysis (SEA). These methods have originally been derived for conditions at ambient pressure. The transmission of sound through single and double plates was investigated in a tube at pressures up to 50 bars with air and helium as fluid. The results of these experiments were compared with the theoretical predictions. Espacially at higher frequencies the agreement between theory and experimental results are good. The main parameter influencing sound transmission isthe wave resistance.