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Guo, Boyun / Computer Assited Petroleum Production Engg 0750682701_chap06 Final Proof page 79 3.1.2007 8:40pm Compositor Name: SJoearun




                                                                                    WELL DELIVERABILITY  6/79
                               Table 6.7 Solution Given by WellheadNodalOil-GG.xls
                               WellheadNodalOil-GG.xls
                               Description: This spreadsheet calculates operating point based on CPR and Guo–Ghalambor TPR.
                               Instruction: (1) Select a unit system; (2) update parameter values in the Input data section; (3) click
                               Solution button; and (4) view result in the Solution section.
                               Input data                    U.S. Field units   SI units
                               Choke size:                   64 1/64 in.
                               Reservoir pressure:           3,000 psia
                               Total measured depth:         7,000 ft
                               Average inclination angle:    20 degrees
                               Tubing ID:                    1.995 in.
                               Gas production rate:          1,000,000 scfd
                               Gas-specific gravity:         0.7 air ¼ 1
                               Oil-specific gravity:         0.85 H 2 O ¼ 1
                               Water cut:                    30%
                               Water-specific gravity:       1.05 H 2 O ¼ 1
                                                               3
                               Solid production rate:        1 ft =d
                               Solid-specific gravity:       2.65 H 2 O ¼ 1
                               Tubing head temperature:      100 8F
                               Bottom-hole temperature:      160 8F
                               Absolute open flow (AOF):     2,000 bbl/d
                               Choke flow constant:          10
                               Choke GLR exponent:           0.546
                               Choke-size exponent:          1.89
                               Solution
                               A                             ¼ 3:1243196 in: 2
                               D                             ¼ 0.16625 ft
                               T av                          ¼ 622 8R
                               cos(u)                        ¼ 0.9397014
                               (Drv)                         ¼ 41.163012
                               f M                           ¼ 0.0409121
                               a                             ¼ 0.0001724
                               b                             ¼ 2.86E 06
                               c                             ¼ 1349785.1
                               d                             ¼ 3.8619968
                               e                             ¼ 0.0040702
                               M                             ¼ 20003.24
                               N                             ¼ 6.591Eþ09
                                                                                    3
                               Liquid production rate, q     ¼ 1,289 bbl/d      205 m =d
                               Bottom hole pressure, p wf    ¼ 1,659 psia       11.29 MPa
                               Wellhead pressure, p hf       ¼ 188 psia         1.28 MPa


                       6.3 Deliverability of Multilateral Well    p wf i  ¼ the average flowing bottom-lateral pressure in
                                                                       lateral i.
                       Following the work of Pernadi et al. (1996), several math-
                       ematical models have been proposed to predict the deliver-  The fluid flow in the curvic sections can be described by
                       ability of multilateral wells. Some of these models are
                       found from Salas et al. (1996), Larsen (1996), and Chen  p wf i ¼ f Ri p kf i ,q i  i ¼ 1, 2, .. . , n,  (6:27)
                       et al. (2000). Some of these models are oversimplified and  where
                       some others are too complex to use.
                         Consider a multilateral well trajectory depicted in  f Ri ¼ flow performance function of the curvic section of
                       Fig. 6.6. Nomenclatures are illustrated in Fig. 6.7. Suppose  lateral i
                       the well has n laterals and each lateral consists of three  p kf i  ¼ flowing pressure at the kick-out-point of lateral i.
                       sections: horizontal, curvic, and vertical. Let L i , R i , and
                       H i denote the length of the horizontal section, radius  The fluid flow in the vertical sections may be described by
                                                                               !
                       of curvature of the curvic section, and length of the  X
                                                                             i
                       vertical section of lateral i, respectively. Assuming the  p kf i  ¼ f hi p hf i  ,  q j  i ¼ 1, 2, ... , n,  (6:28)
                       pressure losses in the horizontal sections are negligible,  j¼1
                       pseudo–steady IPR of the laterals can be expressed as  where
                       follows:
                            	                                     f hi ¼ flow performance function of the vertical section
                       q i ¼ f L i p wf i i ¼ 1, 2, .. . , n,  (6:26)
                                                                       of lateral i
                       where                                      p hf i  ¼ flowing pressure at the top of lateral i.
                          q i ¼ production rate from lateral i     The following relation holds true at the junction points:
                         f Li ¼ inflow performance function of the horizontal
                                                                          i ¼ 1, 2, .. . , n         (6:29)
                             section of lateral i                p kf i  ¼ p hf i 1
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