Analysis of the bottom-hole pressure versus flow rate data obtained from the test yields results that, when plotted on log-log paper, produce a straight line that reflects the stabilized deliverability of the well.Groundwater \(early view July 12, 2014\), doi: 10.1111/gwat.12235)/Rect/Subj(Typewritten Text)/Subtype/FreeText/T(proyster2)/Type/Annot> In the analyses, initial dimensionless time step of t D 0. Wells that are closer to the site are predicted to experience. Well drawdown (h d) is assumed positive when the water level drops in the well. At least one flow rate must then be maintained to stabilization in order to predict the current or future stabilized deliverability of the well. experience drawdowns of less than 0.5 feet at the well as a result of site operations. The isochronal and modified isochronal tests require that a well be produced at four different rates, each for a fixed period of time, separated by shut-in periods. The empirical method is based on holding the head or flow rate constant in order to maintain a target drawdown for as long as possible. case of a fully penetrating stream and pumping well. The method, however, does not lend itself well to the testing of low permeability wells where the time to stabilization given by Eq. Drawdown data were obtained in eight piezometer clusters, located on both sides of the stream. The conventional backpressure test requires that a gas well be flowed to stabilization at four different flow rates. The conventional backpressure test or flow-after-flow test, the isochronal test, and the modified isochronal tests are normally employed to predict the current and future deliverability of a gas well. Predicting the performance of a gas well is a process that has typically relied on using some form of multipoint well-testing procedure. In its simplest application, the new method allows an engineer to predict the AOF of a gas well which, when plotted on log-log paper along with the single stabilized point obtained from the pressure build-up or draw-down test, permits the construction of the stabilized deliverability curve and the determination of its equation. Using the new curves or their general equation, an IPR curve can be constructed. The curves may also be applied to unfractured wells by converting the apparent skin factor obtained from a pressure transient test to an equivalent ratio of external drainage radius to fracture half-length (xe/xf) using the apparent wellbore radius concept. The method utilizes new dimensionless IPR curves that were developed specifically for hydraulically fractured gas wells. Estimation of well efficiency under different pumping rate conditions suggests that the contribution of well loss to the total drawdown varies from 82 to 98 for well D8 and 95.5 to 99.93 for well D10, depending on the pumping rates and the applied models. This paper describes a method for predicting the deliverability of a gas well that requires only pressure build-up or draw-down test data. Their research focused on the development of dimensionless IPR curves for gas wells similar to Vogells curve for oil wells. Several researchers have worked to advance the theory of predicting gas well deliverability using a one-point test. Theis solution may also use distance-drawdown data from multiple wells instead of time. All of these methods require testing a well at a minimum of four flow rates. Hydraulic characteristics of the aquifer are used to predict the. Predicting the deliverability of a gas well is normally accomplished by conducting a four-point backpressure test, an isochronal test or a modified isochronal test.
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