DimensionlessDrawDown: The dimensionles drawdown of well pumping test

In petrmaca/GTest: The Pumping Test for Groundwater wells

Description

The dimensional drawdown of pumping test calcuated using the stehfest algorithm and aquifer parameters.

Usage

DimensionlessDrawDown(Gwinput)

Arguments

Gwinput	list of TD vector of dimensionless time calculated as aquifer Transmisivity[m2/s] * time[s] / well radius [m] / storativity [-], Cbar dimensionless welbore storage constant,,Skin skin effect factor
...	another agruments

Value

The dimensionless drawdown calculated for each time of TD.

References

R. G. Agarwal, R. Al-Hussainy and H. J. Ramey Jr., <e2><80><9c>An Investigation of Wellbore Storage and Skin Effect in Unsteady Liquid Flow: I. Analytical Treatment,<e2><80><9d> SPE Journal, Vol. 10, No. 3, 1970, pp. 279-290.

Stehfest, H. 1970. Algorithm 368 numerical inversion of Laplace transforms. Communication of ACM 13, no. 1: 47<e2><80><93>49.

Walton, W.C. 2006. Aquifer Test Modeling. Boca Raton, Florida: CRC Press, Taylor & Francis Group.

Examples

# Artifitial exmaple of unconfined aquifer with following parameters of pumping test
# Pumped well discharge rate [m3/s]
Q=0.0045
# Aquifer Transmisivity [m2/s]
Transm=0.012
# Well radius [m]
Rv=1.2
# Storativity [-]
STRR=0.0001
# Time [s]
T = c( 1.88,2.36,2.97,3.74,4.71,5.93,7.46,9.40,11.83,14.89)
# Dimesionles time [-]
TD=T*Transm/Rv/Rv/STRR
# Well drawdown during pumping test [m]
S =c(0.006,0.008,0.010,0.012,0.015,0.019,0.024,0.03,0.038,0.047)
# Dimensionless drawdown [-]
dlS = (S*2*3.14*Transm)/Q
# Aquifer parameters
Cbar= 1562.858133
Skin = 4.976677
#calcutating the dimensionless drawdown using stehfest algorithm
Kytlice_2018_15_05 = PumpingTestDataLoad(Q=Q,Storativity = STRR,
Transmisivity = Transm,Radius = Rv,Time = T,DrawDown = S,WellTestType = "IsotropicMediumBesselR")
Gwinput = SetStehfestData(Kytlice_2018_15_05$DimlesTime,10,Cbar,Skin,WellTestType= "IsotropicMediumBesselR")
simDD <- DimensionlessDrawDown(Gwinput)
# Comparison plot
plot(TD,dlS, pch=19,ylab="Dimensionless Drawdown [-]",xlab = "Dimensionless Time [-]")
lines(TD,simDD,col="red")

petrmaca/GTest documentation built on May 29, 2019, 11:44 a.m.