Well testing is an important and valuable tool for assessing the performance of wells. It allows operators to determine the true potential of a well by measuring fluids and other reservoir properties. This information can help improve production rates, estimate reservoir volumes and identify if wells are capable of reaching the production capacity limit. In addition to evaluating the performance of a well, it can also be used for monitoring the health of the formation and the condition of the equipment.
Reservoir fluids produced from a well flow to a test separator and are separated into oil, gas and water. These samples are then sent to a test lab where their individual characteristics are measured. Depending on the type of well, there are several methods that can be used to measure the fluids and other properties. This information can be used to evaluate the performance of the well and its surrounding reservoir and determine which zones contribute to the overall fluid flow rate.
The most common type of well test is a drawdown visit this site or buildup test. This test involves flowing the well at a constant rate until pressure stabilizes (drawdown). Then the well is shut in and pressure is recorded to obtain a more detailed analysis. This can reveal a wide range of parameters, such as reservoir permeability and skin factor, average reservoir pressure and temperature and more.
Flowing test: During a flowing test, engineers will use a wireline formation tester to capture and measure downhole fluids and pressure in the zone of interest. This data can be used to identify the hydrocarbon composition of the mud, gas and oil. It can also be used to identify any contaminants, such as drilling fluids, that have entered the well. The data can then be used to compare with the predicted results of a well’s simulation model.
Interference test: The interference test is another common well testing technique. It provides a large-scale property trend for the reservoir and allows engineers to better understand the reservoir geometry including natural fractures, layering, distance to boundaries and more. This test can also be used to evaluate the effectiveness of the well’s completion design and detect communication between adjacent wells.
Rate transient: A rate transient test is an advanced well testing method that can reduce uncertainty associated with conventional well test analysis by allowing for more accurate modeling of the multiphase flow of reservoir hydrocarbons with fracturing fluids. The method can be applied to both symmetric and unconventional reservoirs.
In order to perform a rate transient test, an engineer will record the pressure and gallons per minute (GPM) of the well during a 60-minute period. The resulting pressure data can be compared to the predicted well response in a reservoir simulation. This can provide more reliable characterization of stimulated rock volume in multifractured unconventional wells, which can help in optimizing the positioning and spacing of wells during field development planning. In addition, it can also be used to assess the impact of fluids from drilled and undrilled wells on the measured pressure.