PE4511 Homework #5 Name ClassID
Short answers
(5 pts) How many types of aquifer geometries? Please illustrate them.
(5 pts) What is the indication of active water influx? Please present the mass conservation equation.
(2 pts) How many types of aquifer flow regimes?
(5 pts) What is the procedure to calculate cumulative water influx using the principle of superposition?
(5 pts) How many methods we discussed to calculate cumulative water influx based on the van Everdingen and Hurst model? What are the differences among them?
(8 pts) Please calculate the cumulative water influx using the pot aquifer model from a pressure drop of 200 psi at the oil-water contact. Reservoir and aquifer have the following properties as in the table:(10 pts) Please calculate the cumulative water influx after 100 days, 200 days, 300 days, and 400 days under the steady state flowing condition. The estimated water influx constant is 130 bbl/day/psi, initial reservoir pressure is 3500 psi, and pressure history as given in the following table:
(10 pts) Please calculate the cumulative water influx at the end of 1, 2 and 5 years into a circular reservoir with an aquifer of infinite extent in the unsteady state flow regime. The initial and reservoir pressure are 2500, 2498, 2496, and 2490 psi, respectively. The reservoir and aquifer properties are provided in the following table:
Given a cylindrical reservoir, its outer radius is 1500 ft, it has an infinite large edge aquifer. The aquifer has the following properties: permeability as 36 md, porosity as 0.19, water viscosity is 1 cp, and total compressibility is 9*10-6 1/psi, aquifer thickness is 60 ft, and encroachment angle is 180o. Pressure is measured at the different time, as illustrated in the following table. Please do the following calculation:
(10 pts) Please calculate the cumulative water influx by the end of 2nd, 4th, 6th, 8th month using van Everdingen model with one step pressure drop (for example, pressure drop at the end of 2nd month is Pi-P2=4000-3800=200 psi). Plot the results.
(10) Please calculate the cumulative water influx by the end of 2nd, 4th, 6th, 8th month using principle of superposition. And plot and compare the difference of your results from methods used in a) and b).
(Bonus 50) Please calculate the cumulative water influx by the end of 2nd, 4th, 6th, 8th month using the half pressure drops method we discussed in the class.
(Bonus 50) Please calculate the cumulative water influx by the end of 2nd, 4th, 6th, 8th month using Tracy-Carter model
T (months) P (psi)
0 4000
2 3800
4 3660
6 3560
8 3490
For this question, you are encouraged to use Excel worksheet. If so, please submit clear specification procedure you did in writing and specification of parameters and results, as seen in the following example. Bonus points varies from 10~50 pts depending on the quality of work.
If you can come up some brief coding for the calculation using Excel Macros, each piece is worth of 100 bonus points.
Each 100 bonus points = additional 5 pts in your homework final evaluation.
You can work on the bonus problems and submit the results until the final week of this semester.