Sökning: "pass-by simulations"

Hittade 4 avhandlingar innehållade orden pass-by simulations.

1. 1. Predicting the sound field from aeroacoustic sources on moving vehicles : Towards an improved urban environment

   Författare :Nicolas Pignier; Ciarán O'Reilly; Susann Boij; Michael Carley; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; pass-by simulations; aeroacoustic sources; urban sound propagation; direct numerical beamforming; linear programming deconvolution; Kirchhoff approximation; moving sources; detached-eddy simulation; Ffowcs Williams-Hawkings; vehicle design; förbifartssimuleringar; aeroakustiska källor; urban ljudutbredning; direkt numerisk lobformning; avfaltning med hjälp av linjärprogrammering; Kirchhoffs approximation; rörliga källor; detached-eddy simulation; Ffowcs Williams-Hawkings; fordonsdesign; Vehicle and Maritime Engineering; Farkostteknik;

   Sammanfattning : In a society where environmental noise is becoming a major health and economical concern, sound emissions are an increasingly critical design factor for vehicle manufacturers. With about a quarter of the European population living close to roads with heavy traffic, traffic noise in urban landscapes has to be addressed first. LÄS MER

3. 2. Simulating rolling noise on ballasted and slab tracks: vibration, radiation, and pass-by signals

   Författare :Jannik Theyssen; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Railway rolling noise; Numerical modelling; Green s functions; Time domain; Spherical harmonics; Slab track; 2.5D FE BE;

   Sammanfattning : Shifting to rail-bound freight and passenger traffic is key in Europe's strategy towards transport decarbonisation. However, increasing railway traffic can increase environmental noise pollution. Rolling noise is often the dominant noise source. It originates from the interaction of the rough running surfaces of wheel and rail. LÄS MER

4. 3. Absorption of Sound : On the effects of field interaction on absorber performance

   Författare :Anna Färm; Mats Åbom; Ragnar Glav; Susann Boij; Gareth Bennett; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sound absorption; Porous absorbers; Bulk reaction; Local reaction; Boundary layer; Grazing flow; Temperature gradients; Surface impedance; Sound field; Pass-by noise; Vehicle and Maritime Engineering; Farkostteknik;

   Sammanfattning : Environmental noise has for decades been a well known problem, especially in urban areas. As noise requirements for vehicles are sharpened, noise reducing concepts are needed in early design stages requiring accurate simulations to support the design. LÄS MER

5. 4. Background road traffic noise synthesis

   Författare :Georgios Zachos; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; background traffic noise synthesis; auralisation; urban sound planning;

   Sammanfattning : As urban planning evolves along with societal life, new requirements that should be met are rising. One of those, is the inclusion of acoustic quality in urban environments, before, during, or after a planning process. To address this for a yet to be built area, metrics are needed that try to quantify acoustic quality. LÄS MER