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Dynamics of Biological Systems, Chapter 2: Development of a General Environmental Control Model

Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org

Citation:  Chapter 2, Pages 2.1-2.55 (doi:10.13031/2013.34917) in Chapter 2, pp. 2.1-2.55 . Copyright 2003 American Society of Agricultural and Biological Engineers, St. Joseph, Mich.
Authors:   John S. Cundiff and Kyle R. Mankin
Keywords:   Headings. 2.1 Introduction, 2.1.1 Conservation of Mass, 2.1.2 Conservation of Energy, 2.2 Moisture Balance, 2.2.1 Humidity Ratio from Dry-bulb Temperature and Relative Humidity, 2.2.2 Humidity Ratio from Dry-bulb and Wet-bulb Temperatures, 2.3 Mass Flow of Dry Air, 2.4 Mass Flow of Moisture, 2.5 Energy Balance, 2.5.1 Passive Solar (Qp), 2.5.2 Supplemental Heat (Qf), 2.5.3 Released Heat (Qr)

First paragraph. Conservation of mass and conservation of energy are the two key issues in the solution of an environmental control problem. To develop these key issues, it is expedient to use the concept of a control volume developed in Chapter 1. The boundary of the control volume can be the entire exterior surface of a building or an arbitrary part of the total volume of product. For example, in the modeling of grain drying, the bulk is divided into thin layers and an individual layer is treated as a control volume.

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