Download or read book Aeroacoustic Noise Prediction of Automotive HVAC Systems written by Matthias Tautz and published by . This book was released on 2019-07-15 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aeroacoustic Noise Prediction of Automotive HVAC Systems written by Matthias Tautz and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Case History Acoustic Diagnostics of an Automotive HVAC System written by T. A. Brungart and published by . This book was released on 1992 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: The heating, ventilation, and air conditioning (HVAC) system of an automobile can be a source of acoustic annoyance, particularly when it is operated under maximum airflow conditions. In order to suggest possible design changes for the purpose of noise control, a systematic characterization of the acoustic sources and mechanisms must be conducted initially. This paper addresses such a characterization for a typical automotive system. The approach is based on acoustic intensity measurements of the stand-alone HVAC system operating under maximum airflow conditions in an anechoic chamber. The experimental data indicate that the centrifugal blower is the dominant source of noise, particularly at low frequencies, while separation zones, the flow over sharp edges within the HVAC system, louver flows, and flow-induced casing vibration are secondary sources of noise that become increasingly important as the frequency approaches 3 kHz. Qualification of these identified sources of sound is aided by detailed flow visualizations conducted underwater on an optically clear HVAC system utilizing similitude.

Download or read book A Method to Predict Automobile Aeroacoustic Near and Far Field Noise written by Douglas William Dietz and published by . This book was released on 2000 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Annual Index abstracts of SAE Technical Papers written by and published by . This book was released on 2006 with total page 1000 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Acoustic Diagnostics of an Automotive HVAC System written by and published by . This book was released on 1991 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: The heating, ventilation, and air conditioning (HVAC) system of an automobile can be a source of acoustic annoyance, particularly when it is operated under maximum airflow conditions. In order to suggest possible design changes for the purpose of noise control, a systematic characterization of the acoustic sources and mechanisms must be conducted initially. This report addresses such a characterization for a typical automotive system. The approach is based on acoustic intensity measurements of the stand-alone HVAC system operating under maximum airflow conditions in the ARL Penn State flow-through anechoic chamber. The experimental data indicate that the centrifugal blower is the dominant low-frequency source of noise, while separation zones and the flow over sharp edges within the HVAC system ducting are secondary sources of noise that become increasingly dominant as the frequency exceeds 3 kHz. Qualification of these identified sources of sound is aided by detailed flow visualizations of the subject system. Recommendations for acoustic improvements to the system are provided.

Download or read book A Computational Aeroacoustic Method for Near and Far field Vehicle Noise Predictions written by N. Sarigul-Klijn and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Noise Sources Characterization of Automotive HVAC Systems written by Vahid Madani and published by . This book was released on 2002 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aero Acoustic on Automotive Exhaust Systems written by Dirk Wiemeler and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: On automotive exhaust systems aero acoustic noise is a dominant and critical noise content, which is clearly objectively and subjectively detectable. Robust test procedures are established but the simulation of this noise content has not gained ground in the real life development processes. This thesis shows that the dominating characteristic of the aero acoustic noise of automotive systems is dipole noise. The simulation of these specific noise sources with classical computational areo acoustics is very cumbersome or even just impossible. The aim of the thesis is a review of the scaling law approach for compact source models, enabling the determination of the sound power emission of discret configurations based on empirical data. Application simulations show that the use of these source models is simple and that the accuracy is acceptable within the geometry limits analysed.

Download or read book Computational Aeroacoustics written by Jay C. Hardin and published by . This book was released on 1993 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aeroacoustic Noise Prediction and Acoustic Optimization of Mufflers written by Jobin Puthuparampil and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Noise control of large diesel and natural gas generators is achieved through industrial mufflers. Design of such mufflers relies heavily on general guidelines. But these guidelines are not suitable for complex mufflers; instead, automated optimization provides an effective means of design. Optimization of a plug flow muffler (PFM) is conducted in this work with two different approaches: 1) a relatively simple gradient-descent algorithm (L-BFGS-B) maximizing the transmission loss of the PFM, and 2) a multi-objective (transmission loss and pressure drop) simulation-based optimization using the Efficient Global Optimization (EGO) algorithm. The EGO algorithm is shown to be well suited for muffler optimization, performing vastly better than the commonly used NSGA-II algorithm. In addition, the initial steps towards the prediction of aeroacoustic noise (self-noise) in mufflers is accomplished through the CFD simulation of the tandem cylinder benchmark experiment.

Download or read book Automotive Acoustics Conference 2015 written by Wolfgang Siebenpfeiffer and published by Springer Vieweg. This book was released on 2019-08-29 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elektrofahrzeuge sind für Entwickler der Fahrzeugakustik ebenso eine Herausforderung wie eine höhere NVH-Performance durch Leichtbaustrukturen und kleinere Motoren mit Turbolader. Die Automobilforschung muss das Akustikmanagement im Fahrzeug neu denken. Die internationale Automotive Acoustics Conference bietet dazu als Fachtagung das notwendige Expertenwissen, um die künftigen Anforderungen an Antriebsstrang, Antriebssysteme und Fahrzeugarchitekturen zu erfüllen. Simulationsprozesse und Verfahren der Multiphysik sind dabei essenziell, um Ruhe in die Passagierkabine zu bringen. Die Konferenz zur car acoustics bietet dazu neustes Expertenwissen.

Download or read book The International Vehicle Aerodynamics Conference written by IMechE and published by Woodhead Publishing. This book was released on 2014-11-12 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerodynamics has never been more central to the development of cars, commercial vehicles, motorbikes, trains and human powered vehicles, driven by the need for efficiency: reducing carbon dioxide emissions, reducing fuel consumption, increasing range and alleviating problems associated with traffic congestion. Reducing vehicle weight makes it more challenging to ensure that they are stable and handle well over a wide range of environmental conditions. Lighter structures are also more vulnerable to aerodynamically induced vibration. Alongside this, customers demand an environment that is quiet, comfortable and maintains their vision of the world around them in all weathers. These aims must be met by designing vehicles that engage customers emotionally, promoting the brand values of manufacturers and operators. This can only be done by collaboration between designers and aerodynamicists. Examine the latest developments in vehicle aerodynamic development Explore opportunities to network and share experiences around different areas Focus on future challenges and the engineering knowledge and technology required to resolve them Discuss other areas of development including handling and stability, tyre aerodynamics and modelling, aeroacoustics and fluid structure interaction

Download or read book Aeroacoustics Acoustic wave propagation aircraft noise prediction aeroacoustic instrumentation written by Ira R. Schwartz and published by . This book was released on 1976 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Noise Prediction Using Hybrid Aeroacoustic Methods for Generic Test Cases written by and published by . This book was released on 2015 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Direct and Large Eddy Simulation X written by Dimokratis G.E. Grigoriadis and published by Springer. This book was released on 2017-10-06 with total page 523 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses nearly all aspects of the state of the art in LES & DNS of turbulent flows, ranging from flows in biological systems and the environment to external aerodynamics, domestic and centralized energy production, combustion, propulsion as well as applications of industrial interest. Following the advances in increased computational power and efficiency, several contributions are devoted to LES & DNS of challenging applications, mainly in the area of turbomachinery, including flame modeling, combustion processes and aeroacoustics. The book includes work presented at the tenth Workshop on 'Direct and Large-Eddy Simulation' (DLES-10), which was hosted in Cyprus by the University of Cyprus, from May 27 to 29, 2015. The goal of the workshop was to establish a state of the art in DNS, LES and related techniques for the computation and modeling of turbulent and transitional flows. The book is of interest to scientists and engineers, both in the early stages of their career and at a more senior level.

Download or read book Aeroacoustic Noise Prediction and the Dynamics of Shear Layers and Jets Using the Nonlinear Parabolized Stability Equations written by Lawrence C. Cheung and published by . This book was released on 2007 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last portion of this study, we present an extension to the PSE that is based on the method of multiple scales. We show how the multiple scale PSE method can be used to handle more general inlet forcing schemes and capture additional frequencies not present in the traditional nonlinear PSE approach. This extended method is also applied to supersonic and subsonic shear layers, and compared to results from DNS calculations.