Abstract: A system for producing a material balance solution for well patterns in a hydrocarbon reservoir is described that automatically optimizes the fluid allocation factors for each well used in determining the solution. The system automatically optimizes estimates for the allocation factors to be used in the material balance solution by randomly generating a first generation of allocation factor strings, each string in the generation assigning allocation factors to each of the wells in the reservoir. A fitness function value is determined for each of the strings by evaluating a fitness function, wherein the fitness function comprises the sum of the differences between computed and measured field pressures for each pattern, and the sum of the differences between target allocation factors and the allocation factors specified within the string for each well. A succeeding generation of allocation factor strings is produced according to a genetic algorithm.

Abstract: A system for producing a material balance solution for well patterns in a hydrocarbon reservoir is described that automatically optimizes the fluid allocation factors for each well used in determining the solution. The system automatically optimizes estimates for the allocation factors to be used in the material balance solution by randomly generating a first generation of allocation factor strings, each string in the generation assigning allocation factors to each of the wells in the reservoir. A fitness function value is determined for each of the strings by evaluating a fitness function, wherein the fitness function comprises the sum of the differences between computed and measured field pressures for each pattern, and the sum of the differences between target allocation factors and the allocation factors specified within the string for each well. A succeeding generation of allocation factor strings is produced according to a genetic algorithm.

Abstract: Natural gas is reinjected into an earth formation for storage and/or stimulating the recovery of hydrocarbon liquids by mixing the gas with water at a pressure sufficient to maintain bubble flow of gas dispersed in a water flowstream in a range of volumetric gas fraction up to about twenty percent of total flow. A water and gas distribution system includes static flow mixers for maintaining uniform distribution of gas bubbles in the water flow stream through the distribution conduits. The mixers may comprise multi-stage bladed mixing elements of the same or opposite pitch and extending across the intersection of branch conduits with the main conduit of the distribution system. The water and gas may be mixed in an injection well having a tubing string extending within the well and having a distal end below the point of injection into an earth formation so that a uniform gas and water mixture enters the formation through the well perforations.