This thesis offers new insights into the fluid flow behavior of automotive centrifugal compressors operating under near-stall conditions. Firstly it discusses the validation of three-dimensional computational fluid dynamics (CFD) unsteady simulations against acoustic experimental measurements using an original procedure based on plane wave pressure decomposition. It then examines the configuration of the CFD cases, highlighting the key parameters needed for a successful calculation. Moreover, it describes both the compressor mean and unsteady flow field from best-efficiency to near-surge operating points. Lastly, it provides readers with explanations of the various phenomena that arise when the mass flow rate is reduced and the compressor is driven to poor and noisy performance. Written for students, researchers and professionals who want to improve their understanding of the complex fluid flow behavior in centrifugal compressors, the thesis offers valuable practical insights into reducing the acoustic emissions of turbochargers.

This thesis offers new insights into the fluid flow behavior of automotive centrifugal compressors operating under near-stall conditions. Firstly it discusses the validation of three-dimensional computational fluid dynamics (CFD) unsteady simulations against acoustic experimental measurements using an original procedure based on plane wave pressure decomposition. It then examines the configuration of the CFD cases, highlighting the key parameters needed for a successful calculation. Moreover, it describes both the compressor mean and unsteady flow field from best-efficiency to near-surge operating points. Lastly, it provides readers with explanations of the various phenomena that arise when the mass flow rate is reduced and the compressor is driven to poor and noisy performance. Written for students, researchers and professionals who want to improve their understanding of the complex fluid flow behavior in centrifugal compressors, the thesis offers valuable practical insights into reducing the acoustic emissions of turbochargers.

Offering the most modern psychological techniques, this guide to breaking the habit of smoking provides useful advice so that readers can avoid paying for costly professional treatments. Using clear and concise language, this book focuses on developing readers' self-control and offers various approaches both for those looking to quit cold-turkey as well as those who prefer a slower approach. Although mostly aimed at smokers attempting to quit, whether it be for the first time or not, this book will also prove useful to doctors, educators, legislators, psychologists, and others who work towards improving healthcare and health education. "Ofreciendo las tecnicas psicologicas mas modernas, esta guia para romper el habito de fumar provee consejos utiles para que el lector no tenga que pagar por tratamientos profesionales costosos. Usando un lenguaje claro y conciso, este libro se enfoca en desarrollar el auto-control del lector y ofrece varios enfoques, tanto para aquellos que quieren dejar de fumar de golpe como para aquellos que prefieren dejar de fumar poco a poco. Aunque mayormente esta destinado a fumadores que buscan romper el habito, ya sea por primera vez o no, este libro tambien sera util para doctores, educadores, legisladores, psicologos y otros quienes trabajan para mejorar la salud y la ensenanza de la salud."