The Measurement of Air Flow: 5th Edition (in SI Units) deals primarily with the measurement (expressed in SI units) of the speed of air in motion relative to solid boundaries or surfaces. The methods described apply not only to air flow but also to the flow of other gases with little, if any, modification, except as regards the numerical values of the various physical properties occurring in the equations. Furthermore, much of the theory applies to the flow of both liquids and gases. Comprised of 13 chapters, this volume begins with an overview of the general principles of the pressure-tube anemometer used in measuring pressure difference from which the speed of flow can be deduced. The reader is then introduced to the characteristics of pitot and static tubes in incompressible flow; pitot and static observations in compressible flow; and the flow of air in pipes of circular cross-section. Subsequent chapters focus on the measurement of incompressible flow in pipes by pitot and static traverse methods; methods of flow measurement based upon the rates of cooling of hot bodies; and the measurement of pulsating flow. This book is intended for students and engineers and for other practitioners concerned with the measurement of the speed of air flow.