ABSTRACT
This chapter establishes the essential groundwork for this book. Therefore, it first starts with the energy units, conversions, and dimensional analysis. The base and derived quantities, relationships between quantities, and quantity equations are discussed. The multiples and submultiples in SI unit system are presented, and an introduction is provided for dimensional analysis. Furthermore, conversion factors for energy related units between SI and I-P are also provided.
The chapter then moves into and briefly reviews thermodynamics, introducing the basic concepts: the laws of thermodynamics, and the energy and mass balance concepts before getting into different modes of heat transfer for different geometries. The chapter then relates the heat transfer analyses to different energy applications, for instance, heat transfer through walls or windows, which is essential for determining heating or cooling loads of buildings. Furthermore, analysis of heat exchangers for numerous applications (also common in greenhouse operations) is presented as well. And then, the chapter introduces the study of psychrometrics, which deals with thermodynamic properties of moist air. Using these properties, engineering situations and processes involving moist air are analyzed, covering perfect gas relations and describing their use in thermal comfort problems, particularly in greenhouse environments. One of the subsections covers fuels, combustion of fuels, theoretical and excess air requirements for combustion, flue gas and carbon emissions, as well as the cost comparisons of different heating fuels. As the piping systems for water, natural gas, oil, etc., are all designed using the principles of fluid mechanics, the chapter then focuses on the required essentials of fluid mechanics. A dedicated subsection covers fundamental fluid mechanics, which is essential for handling general heating, ventilating, and air-conditioning processes. And finally, since solar energy powers virtually everything in the Earth and atmosphere system and is a vitally important energy resource for greenhouse operations, this chapter has a fully dedicated section on light, radiation, characteristics of solar radiation, and relevant data. The solar spectrum, direct and diffuse components of solar radiation, as well as the temporal and spatial distributions of solar energy are studied in depth before the chapter ends.
Plenty of numerical examples are provided in each and every subsection of the chapter to demonstrate and fully grasp the relevant concepts easily.
