Physical-Mathematical Foundations of the Penman Equation from the Perspective of the First Law of Thermodynamics and Energy Balance Theory  

作　　者：Martín Mundo-Molina Enrique De Coss-Gomez 

机构地区：[1]Investigation Centre Faculty of Engineer Autonomous, University of Chiapas, Tuxtla Gutierrez, Mexico [2]Investigation Centre CIDESTA, Tuxtla Gutierrez, Mexico

出　　处：《Journal of Water Resource and Protection》2017年第12期1377-1390,共14页水资源与保护（英文）

摘　　要：The evapotranspiration is indispensable for the planning and management of water resources in watersheds and for the design of important engineering projects. The accuracy of its estimation depends, among other things, on the proper determination of the date and frequency of irrigation. One of the most accurate equations for estimating the reference crop evapotranspiration (ETo) is the Penman-Monteith equation, which was derived from the Penman equation published in 1948, which in turn is based on the energy balance equation. In this paper we present the theoretical foundations of Penman’s equation from the perspective of the first law of thermodynamics and the theory of energy balance as a contribution for the students and engineers who use Penman’s or Penman-Monteith equations in a utilitarian way within the historical and theoretical framework of the origin of this equation.The evapotranspiration is indispensable for the planning and management of water resources in watersheds and for the design of important engineering projects. The accuracy of its estimation depends, among other things, on the proper determination of the date and frequency of irrigation. One of the most accurate equations for estimating the reference crop evapotranspiration (ETo) is the Penman-Monteith equation, which was derived from the Penman equation published in 1948, which in turn is based on the energy balance equation. In this paper we present the theoretical foundations of Penman’s equation from the perspective of the first law of thermodynamics and the theory of energy balance as a contribution for the students and engineers who use Penman’s or Penman-Monteith equations in a utilitarian way within the historical and theoretical framework of the origin of this equation.

关 键 词：EVAPOTRANSPIRATION Penman PENMAN-MONTEITH IRRIGATION REQUIREMENT 

分 类 号：O1[理学—数学]