Hybrid Laminar Flow Control (HLFC) is a promising technology due to its large reductions in skin friction drag. There have been great effort in aerodynamic research over the last decades. Coming closer to a possible integration of the technology into passenger aircraft, the investigation of the suction system, structure and manufacturing becomes more important in research and development. The high possible fuel savings of the HLFC technology are reduced by various failure modes and conditions where laminarity is lost. Extra contingency fuel for these cases can keep the operational reliability of the aircraft high, but strongly reduces the efficiency. So the objective is to minimize the loss of laminarity where possible. Some conditions, such as cirrus cloud encountering, that result in a total loss, can not be avoided (with todays route planning). By taking reliability aspects into account for the system design, it is possible reduce the impact of component failures. In this paper, different system architectures have been analyzed with respect to system reliability. It has been shown that it is not reasonable to improve the reliability on subsystem-level, because the system effort would be too high. There are two promising approaches: the first is to have a higher number of subsystems and to take into account that one or maybe two of them can fail. The k-out-of-n study showed, that the probability that two or more subsystems fail is very low. Therefore it is possible to guarantee a certain percentage of the overall system function. The second approach is the use of a cross-linked HLFC system, where the port and starboard wing suction systems are connected by a cross duct. In failure cases the compressor on one side can operate both sides simultaneously. The system failure rate was decreased significantly with this approach. The disadvantages are that the components are oversized for normal operation and the cross ducting between the two wing suction systems represents extra weight. The reliability analyses also showed, that the plenum chamber and ducting are important. Due to space constraints it is unlikely that they will be redundant, so their failure rate will limit the overall failure rate.
System reliability analysis of HLFC suction system architectures
2013
13 Seiten, 9 Bilder, 2 Tabellen, 25 Quellen
Conference paper
Storage medium
English
Suction System Design for Transonic HLFC Wing
AIAA | 2022
|Suction System Design for Transonic HLFC Wing
TIBKAT | 2022
|Optimal Suction Design for HLFC Applications
AIAA | 2003
|AERODYNAMIC DESIGN AND ANALYSIS OF HLFC WINGS WITHIN THE EUROPEAN PROJECT HLFC-WIN
British Library Conference Proceedings | 2022
|