AN OBJECT-ORIENTED GREENHOUSE SIMULATION SOFTWARE SYSTEM .2. DESCRIPTION, VALIDATION AND USE OF A SIMPLE-MODEL

A simple model of greenhouse heat and mass exchanges was written in the Smalltalk object-oriented programming language and was integrated into a general greenhouse climate control and management software system (GX). The structure, operation and performance of the heat and mass exchange simulation subsystem is described and sample results of its use are given. The results show that the GX simulator can emulate the behavior of the greenhouse ecosystem and of its climate control system. Hence, by using the GX simulation subsystem, the results from a simulation using one control strategy can be compared to results from a simulation run with a different strategy. One can then determine the potential savings in terms of energy or other inputs (CO2, water, etc.) associated with the use of a given strategy. The GX-based simulator has shown potential for both teaching and research applications.