Sökning: "aircraft panel"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden aircraft panel.

1. 1. Acoustical Characteristics of Aircraft Panels

   Författare :Bilong Liu; Leping Feng; Jie Pan; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; sound transmission loss; stiffener; stiffening; aircraft panel; cylindrical shell; turbulent boundary layer; TBL; noise; sound radiation; Acoustics; Akustik;

   Sammanfattning : A deterministic approach based on a modal expansion and modal receptance method has been developed to evaluate the airborne sound insulation of aircraft panels with stringer and ring frame attachments. Furthermore, this method was extended to predict the noise radiation of stiffening panel subjected to TBL excitation. LÄS MER

3. 2. Sound transmission through aircraft panels

   Författare :Biong Liu; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sound transmission loss; stiffener; stiffening; aircraft panel; cylindrical shell; Vehicle engineering; Farkostteknik;

   Sammanfattning : .... LÄS MER

4. 3. Cost Optimization of Aircraft Structures

   Författare :Markus Kaufmann; Dan Zenkert; Malin Åkermo; Per Wennhage; Erik Lund; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aircraft structures; optimization; cost estimation; manufacturing cost; direct operating cost; multiobjective optimization; multidisciplinary optimization; composites; airframe design; Vehicle engineering; Farkostteknik;

   Sammanfattning : Composite structures can lower the weight of an airliner significantly. Due to the higher process complexity and the high material cost, however, the low weight often comes with a significant increase in production cost. The application of cost-effective design strategies is one mean to meet this challenge. LÄS MER

5. 4. Numerical methods for load and response prediction for use in acoustic fatigue

   Författare :Johan Nilsson; Byggnadsmekanik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustic fatigue; Sonic fatigue; Computational Fluid Dynamics; Large Eddy Simulation; Finite Element Method; Random response analysis; Separated flow; High Re; Backward-facing step; Fence flow; Aircraft; Proper Orthogonal Decomposition; Acoustic fatigue; Sonic fatigue; Computational Fluid Dynamics; Large Eddy Simulation; Finite Element Method; Random response analysis; Separated flow; High Re; Backward-facing step; Fence flow; Aircraft; Proper Orthogonal Decomposition;

   Sammanfattning : Acoustic fatigue can occur in structural elements of an aircraft exposed to very high sound pressures. To deal with acoustic fatigue, mainly empirical methods have been applied and often late in the design phase. Current design guidelines have three main limitations. First, they do not say anything about the load intensities. LÄS MER

7. 5. A Panel Method for Supersonic Flow

   Författare :David Pettersson; Per Weinerfeldt; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MATHEMATICS; MATEMATIK;

   Sammanfattning : Supersonic airflow is usually described by a nonlinear hyperbolic system of equations. In this thesis we consider an aircraft represented by a union of thin plates orthogonal to the direction of Right, and describe the derivation of an approximate linear model for the airflow around it. The linear model is reduced to a system of integral equations. LÄS MER