Expert Systems Research And Applications In Sand

Expert system is a program system with abundant professional knowledge and experiences. Through application of artificial intelligence technology and computer technology, according to knowledge and experiences provided by one or several experts in special professional domain, expert system can reason, judge and simulate decision process of human expert to solve complex problems which is difficult for human expert. In a word, expert system is a computer program system which can simulate human expert to solve speciality problems.Along with requirement of oilfield development, sand control measure is an important method for solving sand endangerment of oil well and enhancing oilfield development level. At present, sand production well numbers gradually increase in some oilfields and there are large numbers of operation well need sand-controlling every year. Because of complex geological and exploitation reasons for sand-production well, it is very difficult to judge whether oil well will produce sand in the process of production and then take proper sand control technologic measures. Field monitoring and analysis are mainly based on accumulative basic data and network data through application of artifical statistical method. However, basic data tracking and analysis need consuming a great quantity of manpower but human error is big which can influence scientific analysis and decision.Combined with expert system theory and oilfield sand-control technology, on the basis of analyzing theory foundation, method, strategy, technology and criterion of sand-control, making full use of professional knowledge, staff experiences and lessons of sand-control, applying knowledge organization and expression, knowledge description and acquisitions, inference method and strategy to sand-control technology, constructing production rule based on gray correlative mathematical model, and then through forward inference mechanism, comprehensive sand-control analysis and evaluation system based on expert system theory and technology was constructed with C# language. It has obtained successful application in Dagang oilfield. At the same time, the system is an open system which can supplement new sand-control technology along with perpetual study of expert knowledge. The system has functions of predicting sand-production of formation, studying sand-production mechanisms and regulations of reservoir, analyzing sand-control experiences of operated oil-well, selecting proper sand-control method, optimizing operation parameters and calculating productivity. The system is economically beneficial for improving accuracy and timeliness of sand-control, decreasing staff routine work amount and decreasing expense of sand-control operation.