Abstract:

The formation of preponderance flow path will affect the result of water injection in a reservoir. How to recognize and predict
it becomes the focus of this research. In this paper, a method has been proposed to predict dominant flow path using ant colony
algorithm based on the theory of development fluid potential. It is believed that a development fluid potential includes gravitational
potential energy, pressure energy, kinetic energy and interfacial energy. The difference in fluid distribution in a reservoir determines
the differences of fluid potential in the reservoir. Ant colony algorithm is introduced into the reservoir development, and it is considered
that the formation of both the ant migration path and the preponderance flow path in the reservoir have the characteristics of regularity,
stochastic and optimality. The model of ant colony algorithm based on fluid potential field is proposed. The new methods have beenused in Donghe 1 oilfield, after establishing the fluid potential model in a reservoir, ant colony algorithm simulation is conducted in
fluid potential profile crossing wells. In initial simulation stage, the distribution of high density pheromones is different among different
rhythm layers controlled by development fluid potential distribution differences in inner layer, which means that the distributions of
preponderance flow path are different in different layers. In later simulation stage, controlled by fluid potential distribution differences
interlayer, high concentration pheromones are mainly distributed in the 2-2, 3-1 and 3-2 layers namely, the preponderance flow path is
well developed in these layers. Dynamic data have been used to verify it and the results are in good agreement.

Key words: preponderance flow path, fluid potential, reservoir development, ant colony algorithm