Data lay row col rw rskin kskin b c p cwc pp input

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Unformatted text preview: they vary along the length of the open interval of the well (in which case any negative value should be specified above and the actual values then specified for each node or open interval in dataset 2d below). For example, if Rw = -1, then it is assumed that Rw varies along the length of the well and a real value of Rw must be defined for each node (or open interval) of this well in dataset 2d. Table A1–1.  Summary of parameter definition requirements for available well-loss options. Losstype NONE THIEM SKIN GENERAL SPECIFYcwc Parameter definition requirements for datasets 2c and (or) 2d RW — √ √ √ — Rskin — — √ — — Kskin — — √ — — B — — — √ — C — — — √ — P — — — √ — CWC — — — — √ For each node (or open interval) of this well the user must use either input format 1 or input format 2; in either case, dataset 2d must have │NNODES│ records: Input format 1, for NNODES > 0 2d-1. Data: LAY ROW COL {Rw Rskin Kskin B C P CWC PP} Input format 2, for NNODES < 0 2d-2. Data: Ztop Zbotm ROW COL {Rw Rskin Kskin B C P CWC PP} LAY, ROW, COL are the layer, row, and column numbers of each model cell (node) for the current well. If NNODES > 0, then a total of NNODES model cells (nodes) must be specified for each well (and dataset 2d must contain NNODES records). In the list of nodes defining the multi-node well, the data list must be constructed and ordered so that the first node listed represents the node closest to the wellhead, the last node listed represents the node furthest from the wellhead, and all nodes are listed in sequential order from the top to the bottom of the well (corresponding to the order of first to last well nodes). A particular node in the grid can be associated with more than one multi-node well. Ztop, Zbotm are the top and bottom elevations of the open intervals (or screened intervals) of a vertical well. These values are only read if NNODES < 0 in dataset 2a. The absolute value of NNODES indicates how many open intervals are to be defined, and so must correspond exactly to the number of records in dataset 2d for this well. In the list of intervals defining the multi-node well, the data list must be constructed and ordered so that the first interval listed represents the shallowest one, the last interval listed represents the deepest one, and all intervals are listed in sequential order from the top to the bottom of the well. If an interval partially or fully intersects a model layer, then a node will be defined in that cell. If more than one open interval intersects a particular layer, then a length-weighted average of the cell-to-well conductances Appendix 1—Data Input Instructions for Multi-Node Well (MNW2) Package 49 will be used to define the well-node characteristics; for purposes of calculating effects of partial penetration, the cumulative length of well screens will be assumed to be centered vertically within the thickness of the cell. If the well is a single-node well by definition of LOSSTYPE = NONE and the defined open interval straddles more than one model layer, then the well will be associated with the cell where the center of the open interval exists. LOSSTYPE variables if the relevant variables were set to a negative value in dataset 2c, then that means that they vary in value among nodes (or open intervals, if NNODES < 0) and should be defined here in dataset 2d according to the definitions given under dataset 2c. Which values are specified here, if any, depends on which were set to a negative value in dataset 2c. PP is the fraction of partial penetration for this cell (see PPFLAG in dataset 2b). Only specify if PPFLAG > 0 and NNODES > 0. Note 5: If NNODES < 0 and elevations indicate multiple well screens or open intervals within a single model layer, then the model will assign a single equivalent composite well screen for the node based on the ratio of the screen length to layer thickness (see additional discussion in text). However, if CWC values are specified explicitly by the user, then it is assumed that these values are already appropriate for the actual length of screen and are not further adjusted by this ratio (that is, equation 37 is not applied). If PUMPLOC ≠ 0: 2e. Data: {PUMPLAY PUMPROW PUMPCOL} {Zpump} PUMPLAY, PUMPROW, and PUMPCOL are the layer, row, and column numbers, respectively, of the cell (node) in this multi-node well where the pump intake (or outflow) is located. The location defined in dataset 2e should correspond with one of the nodes listed in 2d for this multi-node well. These variables are only read if PUMPLOC > 0 in 2b. Zpump is the elevation of the pump intake (or discharge pipe location for an injection well). Zpump is read only if PUMPLOC < 0; in this case, the model assumes that the borehole is vertical and will compute the layer of the grid in which the pump intake is located. Note 6: If the intake location (or discharge point for an injection well) is specified by node and that node does not correspond with...
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This document was uploaded on 01/20/2014.

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