溫室環控工程決策支援軟體之建立IV.溫室通風系統設計

Development of Decision Support Software for Greenhouse Environmental Control. IV. Design of Greenhouse Ventilation Systems

Two decision support software to support the natural ventilation and forced ventilation systems design were developed using MATLAB. The first program, entitled 'NV', short for Natural Ventilation, is based on steady-state energy balance. The second program, entitled 'VETH', is based on simultaneous steady-state energy balance and mass balance analysis. VETH deals with the coupled relationships of Ventilation, Evapotranspiration, Temperature and Humidity. Forced ventilation alone, pad and fan evaporative cooling system and fogging system designs are all within the scope of analysis utilizing the VETH software. Subprograms to calculate amount of water evaporated of a fogging system was included in VETH program. An example for designing and/or operating a fogging system is demonstrated using the VETH program. Both programs are user friendly and can be used as teaching/research tools in the field of controlled environment agriculture (CEA). 本文旨在介紹使用MATLAB程式語言建立的自然通風與強制通風系統設計軟體。第一套軟體取名為NV，為英文的自然通風（natural ventilation）的首字，係基於穩態能量守恆。第二套軟體取名為VETH，係基於穩態能量與質量守恆，探討通風（ventilation），蒸發散（evapotranspiration），溫度（temperature）與溼度（humidity）四者之間的關係。舉凡強制通風，使用水簾或噴霧系統的蒸發冷卻降溫系統均屬VETH軟體的探討範圍。本文同時示範如何使用VETH軟體設計噴霧系統。此兩套軟體頗適合溫室環境控制工程領域之教學，研究與實務分析之用。