In engineering, fluid flow and programming is a big deal. A thorough understanding of fluid flow fundamentals is a requirement for any mechanical engineer. Whether your sizing a pump for a pipeline, designing a heat exchanger, or trying to alleviate bottlenecks in pipeline gathering systems, fluid flow shows up in many cases in our profession/career. …
A dry gas reservoir is a reservoir that contains only gas. Further, the produced fluid is only gas, i.e. no liquid condensate drops out at the surface. Once again, to produce the material balance equation for a dry gas reservoir, we must consider the initial state and current state of the reservoir. At the same …
A wet gas reservoir is a reservoir that contains only gas. However as the gas rises to the surface, liquid drops out due to a decrease in temperature. Once again, to produce the material balance equation for a wet gas reservoir, we must consider the initial state and current state of the reservoir. In the …
A gas condensate reservoir is a reservoir that drops out liquid condensate in the reservoir as the reservoir falls below the dew point pressure. Once again, to produce the material balance equation for a gas condensate reservoir, we must consider the initial state and current state of the reservoir. In the back of our mind …
A saturated reservoir is a reservoir where the reservoir pressure has fallen below the bubble point pressure line. Black oil and volatile oil reservoirs exhibit saturated reservoir behavior, thus their material balance derivations are identical. Once again, to evaluate any material balance situation, we must consider the initial state and current state of the reservoir. …
If one understands thermodynamic states, one can get really good at deriving material balance relationships for different reservoirs. It’s simple, your first state is initial reservoir pressure and your second state is a pressure below reservoir pressure. For every material balance situation you are evaluating the reservoir at states during the depletion process. Then you …
The reservoir can produce different types of fluids. Each different fluid type has characteristics that petroleum engineers need to be aware of in order to produce the reservoir efficiently. Generally the reservoir fluid types are classified into 5 separate categories from a phase diagram. They are: Black Oil Volatile Oil Gas Condensate Wet Gas Dry …
In high school we all learn about the single phase diagram for pure substances. Unfortunately, petroleum engineers don’t normally use it. In petroleum engineering we are dealing with multiple-component mixtures. In these cases, the phase diagram is different. Instead of a single line separating the vapor and liquid phases, there is a two phase region …
So far we have considered reservoir pressures maintained above the dew point. At reservoir pressures above the dew point, only single phase gas exists. At pressures below the dew point, condensate evolves out of the gas becoming oil condensate in the reservoir. When this occurs, gas and oil coexist in the reservoir. Under these circumstances, …
In past discussions we looked at how to keep track of reservoir produced volumes below and above the bubble point for oil reservoirs. For gas reservoirs, we do the exact same thing using a separate set of formation volume factors and ratios. In some gas reservoirs, condensate evolves out of the gas as it is …
Previously we discussed the two phase oil formation volume factor. It accounted for both free gas and oil in the reservoir and had units of . In order to relate the liberated gas volumes to reservoir barrels, a gas formation volume factor () was developed. An illustration of how gas formation volume factor is defined …
So far we have considered reservoir pressures maintained above the bubble point. At reservoir pressures above the bubble point, only single phase oil exists. Below the bubble point, solution gas evolves out of the oil becoming free gas in the reservoir. When this occurs, the oil and gas coexist in the reservoir. When multiple phases …