An Expert System for micro-irrigation systems design

System design is one of the most important factors to obtain the full potential of a micro-irrigation system. Micro-irrigation system design is based on a large number of theoretical, rational and empirical relationships and is a time-demanding job. An expert system would be of great help by supplying designers with various levels of experience with a knowledge base. In this paper we examine the criteria involved in implementing an expert system to be used in micro-irrigation system design and present the designing procedure in a format of rules or mathematical models so that it can be programmed in an expert system. The expert system proposed comprises three modules: emitter characteristics, sub-unit characteristics, and distribution pipe sizing and evaluation. The emitter characteristics module helps in the selection of emitters according to their flow rates, operating pressure, discharge exponent, manufacturer's coefficient, number of emitters per plant and emission uniformity. The sub-unit characteristics module concerns determination of the potential number of sub-units in the whole system and the surface area and shape for each sub-unit. The distribution pipe sizing and evaluation module identifies the lengths and diameters of pipes used in the distribution system and their location in the field and evaluates the adequacy of the designed system. At present the ES analytically considers technical optimisation only, whereas economic optimisation is sought through empirical norms as found in the literature, and is only applicable for rectangular sub-units.