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develop a presence in social media, etc. Interns will be selected competitively by the Acoustics Today Advisory Committee at the May meeting of ASA. Selected individuals will receive a small honorarium at the end of their internship as well as free registration at ASA meetings (if they attend) while they are interns. Interns will also be listed on the magazine masthead during their internship and will be invited to participate in
book Review Continued from page 49
Still, in order to keep the text accessible for a graduate student audience, the author does well not to assume the reader is an expert in any one of these fields and includes enough back- ground for the text to stand on its own.
Chapter 1 presents an overview of all the basic equations and notational to set the stage for the rest of the text. This allows the reader to quickly become comfortable with the nota-
tion which is complicated because of the broad nature of the content. The four page nomenclature section at the end of Chapter 1 is nicely formatted, but I would have preferred that is was printed on the inside of the front/back cover to make it easier to access.
The remainder of the text is arranged into three main sections. Section one (chapters 2–6) lays the framework for the fol- lowing sections by examining acoustic, vortical, and entropy disturbances in turn assuming the reader has had only an introductory course in fluid mechanics. Section two (chapters 7–9) deals with flame-flow interactions assuming the reader has only an undergraduate exposure to combustion. The discussion deals with ignition and internal flame processes such as burning rates and extinction. The discussions on flow disturbances are tied into their impact on flame dynamics.
Finally, section three (chapters 10–12) looks at transient and time-harmonic phenomena such as flashback and methods for stabilization. The final two chapters deal with forced response both from the perspective of the flame dynamics and the heat release. These are the most applied chapters in the text and offer many suggestions and topics for further exploration.
The layout of the book has some nice features. Each chap- ter has its own references section and, with the exception of Chapter 10, a set of exercises. The exercises are primarily ana- lytical in nature (derivations, proofs, etc.), which is appropri- ate for the target audience. There are “aside” sections within
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the text that offer focused discussions of related topics that either clarify or expand on topics in the main text. For ex- ample, the section on “general results for temporal instability” in Chapter 3 includes an aside on “vortex mutual induction.” This gives the reader a glimpse into topics that are beyond
the scope of the text but are central to a full understanding of combustion dynamics.
As with any text written concurrent to active research, some concession must be made on topics of contention. For example, in Chapter 2, the basic discussion of flow perturba- tions is couched in terms of a triple decomposition such that a flow quantity is separated into a base value, an ensemble mean quantity exhibiting the coherent structures, and a time varying component identified with turbulent fluctuations.
The author comments that the time average, or base value, is representative of the laminar flow that would exist if the same boundary conditions were imposed in the absence of turbu- lence. This is a debatable position because it is simple to prove that turbulence itself modifies the mean flow in an insepa- rable manner, so it is not correct to assume that the base flow can be equated to a laminar flow. For this reason, the triple decomposition is difficult to justify and even more difficult
to demonstrate in practice. But, in the absence of some other better formulation, the author adopts this common approach. The result of the author’s approach is a text that is very acces- sible and can also act as a valuable reference for the seasoned researcher. Because of the assumed knowledge base of the target audience, the text can act as an introduction to com- bustion for those coming strictly from a physical acoustics
or fluid mechanics background. The inclusion of numerous references provides an excellent starting point for a more focused study. And finally, the avoidance of electronic means of enhancing the text ensure that longevity of this work as an excellent resource.
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