000 04694nam a2200421 4500
005 20260818132652.0
008 180598 th eng
035 _a.b10030815
099 9 _aAIT Thesis no. WA-83-20
100 1 _aGamboa, Renato Simon
245 1 2 _aA groundwater simulation model for well fields at the Agno River Basin :
_bCentral Luzon, Philippines
260 _aBangkok :
_bAsian Institute of Technology,
_c1982
300 _aix, 121 p.
490 1 _aThesis ;
_vno. WA-83-20
500 _aA thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering, School of Engineering and Technology
502 _aThesis (M.Eng.) - Asian Institute of Technology, 1982
520 _aThe study was aimed at developing a computer model that will simulate the movement of groundwater at the Agno Groundwater Basin, Central Luzon, Philippines. The basin which is about 50 km by 54 km was modeled using a variable grid system. The finite difference equation developed for the model was solved by the modified interactive alternating direction implicit method using the Thomas Algorithm. The computer equivalent of the model was written in FORTRAN language and run in the IBM System/3031. Two grid systems were tried: 50 x 50 grid (800m x 2000m grid size) and 90 x 90 grid (400 m x 1000 m grid size) using two time increments: 30 days and 90 days. After testing for computer storage and time usage, and consistencies of computed results, the 50 x 50 grid system and 90 days time increment was used in the later part of the study. The aquifer type treated were two types: unconfined and confined. Further, the constant boundary treatments were al so two types. The first type is constant head throughout the simulation period, that is, the head is held at a constant value for the whole of the simulation period. The other is constant head at a time increment, that is, the head is held constant although out the iterations of a time step calculations. Calibration was done in two steps: blanket and selected adjustments of model parameters. For the comparison of computed results, available records on piezometric head observations and maps on piezometric head distribution were utilized. The model calibration resulted to a close duplication of the recorded responses on a general basis. The flow domain of the model was divided into four well field areas and each of which is considered as upstream or downstream well field according to its relative position in the general direction of the ground water flow. Using these arbitrary divisions of the modeled area, three different areal distribution of pumpings were developed for purposes of simulation. The three pumping schemes are: Scheme I - Uniform Pumping (all the wells in the well fields start pumping at the same time) , Scheme II - Upstream Start of Pumping (wells at the upstream well field start pumping first followed by the other well fields in the downstream direction) , and Scheme III - Downstream Start of Pumping (wells at the downstream well field start pumping first followed by the other well fields in the upstream direction) . Using the information on the crops to be planted, its water requirements and the cropping calendar for the modeled area, the groundwater withdrawals for each pumping scheme were determined and utilized to predict the responses of the aquifer.
650 0 _aWater, Underground
_xSimulation methods
650 0 _aWater, Underground
_xPhilippines
_xAgno River Basin
700 1 _aGupta, Ashim Das,
_eChairperson
700 0 _aTawatchai Tingsanchali,
_eExamination Committee
700 1 _aChristoph, Ing. Fried,
_eExamination Committee
710 2 _aUS-ASEAN Development Cooperation Programme,
_eScholarship Donor
810 2 _aAsian Institute of Technology.
_tThesis ;
_vno. WA-83-20
856 _3Full-Text
_uhttp://203.159.5.9/ait-thesis/detail.php?q=B21420
907 _a.b10030815
_bmnait
_cs
902 _a241009
998 _b2
_c951012
_dm
_ea
_fs
_g2
945 _lmnait
945 _lmnait
945 _lmnarc
942 _c20
942 _c40
909 _aBarcode : 30050003050209
_bCREATED : 1994-05-16
_cRECORD # : i10014275
_dLPATRON : 0
_eLCHKIN : -
_f# RENEWALS : 0
_g# OVERDUE : 0
_hIUSE3 : 0
_iTOT CHKOUT : 0
_jTOT RENEW : 0
909 _aBarcode : 30050003050191
_bCREATED : 1994-05-16
_cRECORD # : i10014287
_dLPATRON : 0
_eLCHKIN : -
_f# RENEWALS : 0
_g# OVERDUE : 0
_hIUSE3 : 0
_iTOT CHKOUT : 0
_jTOT RENEW : 0
909 _aBarcode : 30050160035894
_bCREATED : 2016-05-02
_cRECORD # : i12877694
_dLPATRON : 0
_eLCHKIN : -
_f# RENEWALS : 0
_g# OVERDUE : 0
_hIUSE3 : 0
_iTOT CHKOUT : 0
_jTOT RENEW : 0
999 _c52256
_d52256