Search for dissertations about: "duct air"

Showing result 1 - 5 of 32 swedish dissertations containing the words duct air.

2. 1. Integrated Duct Aerodynamics

   Author : Elias Siggeirsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DDES; RANS; CFD; Compressor duct; Spalart-Allmaras;

   Abstract : Air traffic is rapidly increasing, with no sign of slowing down, resulting in increased green-house gases emission. With emission criteria becoming stricter every year, the aircraft design is subjected to continuous improvements. The development of more efficient aircraft engines plays a central role in the strive towards lower emission levels. READ MORE

4. 2. Studies of flow duct acoustics with applications to turbocharged engines

   Author : Hans Rämmal; Hans Boden; Mats Åbom; Antonio Torregrosa; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; IC-engine; turbocharger; duct termination; flow duct; exhaust system; inlet system; acoustic source; one-port; two-port; source model; transmission loss; two-port matrix; reflection coefficient; source strength; multi-load method; Acoustics; Akustik;

   Abstract : A number of experimental and theoretical studies, performed in the field of technical flow duct acoustics are presented in this thesis. The acoustical methods treated are implemented on turbocharged IC-engines and engine gas exchange system components. A new method based on the well-known two-load technique has been developed. READ MORE

5. 3. Aerodynamics of an Aeroengine Intermediate Compressor Duct: Effects from an Integrated Bleed System

   Author : Elias Siggeirsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Intermediate Compressor Duct; S-shaped duct; DDES; Hybrid RANS LES; Dual-time-stepping; Bleed system; rotor off-take; SBES; CFD; Turbomachinery;

   Abstract : With the successful development of high-bypass-ratio turbofan engines, major aerodynamic components have been optimized and continuous efficiency improvements are getting harder to maintain. Therefore, to meet the requirements of lower emission of greenhouse gases, auxiliary modules such as intermediate ducts are receiving increasing interest. READ MORE

6. 4. Acoustic Characterization of Turbochargers and Pipe Terminations

   Author : Heiki Tiikoja; Mats Åbom; Francisco Denia; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustical two-port; turbocharger; transmission loss; sound generation; compressor; turbine; IC-engine; inlet system; exhaust system; flow duct; duct termination; reflection coefficient;

   Abstract : In search for quieter engines there is a need for a better understanding of the acoustic properties of engine intake and exhaust system components. Besides mufflers which have the purpose of reducing pressure pulses originating from the internal combustion (IC) engine, there are many components in a modern car exhaust and intake system, e.g. READ MORE

7. 5. Turbulent Forced Convection Air Cooling of Electronics with Heat Sinks Under Flow Bypass Conditions

   Author : Hans Jonsson; KTH; []
   Keywords : forced convection; heat transfer; pressure drop; turbulent; air cooling; bypass; plate; strip; pin; fin; heat sink; electronics; experimental; numerical; CFD; TECHNOLOGY; TEKNIKVETENSKAP;

   Abstract : Air cooling is still the dominant method for dissipating theheat produced by electronic components. In a typical electronicdevice, the components are situated on a Printed Circuit Board(PCB). For most applications natural convection is sufficientto cool the components. READ MORE