Submitted to: Encyclopedia of Agricultural, Food, and Biological Engineering
Publication Type: Book / Chapter
Publication Acceptance Date: January 28, 2002
Publication Date: August 14, 2003
Citation: FOX, R.D., DERKSEN, R.C. AIRFLOW MEASUREMENTS. ENCYCLOPEDIA OF AGRICULTURAL FOOD AND BIOLOGICAL ENGINEERING. 2003. DOI: 10.1081/E-EAFE 120006879. p. 21-24. Technical Abstract: Typical agricultural and food engineering applications where measuring air flow is required include pipe flow for food processing; flow in ducts for grain, fruit and vegetable drying and storage; flow in open areas such as room ventilation, machinery and wind velocities. There are many different methods for measuring airflow inconduits and in open spaces. This article summarizes the basic principles important to air flow measurement such as the equation of continuity, Bernoulli's theorem and Reynolds number. Then brief summaries of the principle of operation of fourteen of the most common airflow measurement methods are presented. In some cases, simplified drawings of basic equipment design are shown. This article introduces a broad cross-section of flow measuring instruments that can be used in agriculture and food engineering applications. Readers can use this synopsis of advantages and disadvantages of airflow measuring devices to assist in selecting suitable instruments for their particular application.