4-1Study Area
4-1-1Location
Al-Tuwaitha (Nuclear Research Center ) is located about several kilometers south of the southern edge of Baghdad and within the Baghdad Governorate , between 44 27E and 44 35 E Longitude and 33 10 N and 33 15 N Latitude, and covers 1.2 square km. Aand the Tigris River passes near it fig (4-1). Lland use within 10 km of Al-Tuwaitha is predominately agricultural with scattered houses and villages in the outlying areas. No oil fields or refineries are located nearin the immediate vicinity of Al-Tuwaitha. In the past decade, agricultural operations have increased in the vicinity of Al-Tuwaitha.
4-1-2 Climate Al-Tuwaitha has a hot, dry climate , vassal to Baghdad climate that considered …show more content…
For steady-state models, the fixed head cell values should be the actual values and remain constant during the flow simulation. Used the value of initial hydraulic head for the cells that defines active cells in the last column in model equals to 29.7 m as fig (4-5)[] , while the active cells used 27.6 m where used value of minimum surface water elevation of Tigris river to begin toward a solution. [] . Either the fixed cells that represent the river used three values different in three scenarios , where used minimum , average , and maximum water surface elevation of Tigris river in three scenario . Tthe model simulated for three scenarios based on the values of elevation water of Tigris river in minimum , average , and maximum [].
Scenario 1 : used the values was 27.6 m
Scenario 2 : used the value was 28.7 m, and
Scenario 3 : the value 29.8 m was used . …show more content…
When the best match between observed and calculated values was found. The calibration target can also be achieved by automated parameter estimation or manual adjustment by trial and error procedure . The steady state model was recalibrated using seven7 head well data at different locations as fig (4-4), that obtained from previous studies .the steady- state model was calibrated by adjusting the hydraulic conductivity with manual trial and error method . Where calibration took more of 70 runs to determine suitable hydraulic conductivity for reaching to the minimum error between the observed and calculated heads.
4-2-2-9 Steady-state model