| omega_constants {kitagawa} | R Documentation |
Calculate any constants that depend on angular frequency \omega
Description
This function accesses the appropriate method to calculate the
\omega-dependent constant associated with the choice of c.type.
This function is not likely to be needed by the user.
Usage
omega_constants(omega = 0, c.type = c("alpha", "diffusivity_time"), ...)
## Default S3 method:
omega_constants(omega = 0, c.type = c("alpha", "diffusivity_time"), ...)
Arguments
omega |
frequency, |
c.type |
the constant to calculate |
... |
additional params passed to calculator. In the case of
|
Details
What is "omega"?
The name is in reference to
radial frequency \omega, which is defined as
\omega \equiv 2 \pi / \tau
where \tau is the period of oscillation.
What is the "alpha" calculation?
The parameter \alpha is defined as
\alpha \equiv r_w \sqrt{\omega S / T}
where r_w is the radius of the well,
where S is the storativity, and T is
transmissivity. See the parameter ... for details
on how to pass these values.
This definition is common to many papers on the topic. For example,
it corresponds to Equation 12 in Kitagawa et al (2011).
Because the computation of \alpha depends also on physical
properties, additional parameters can be
passed through (e.g. the transmissivity).
What is the "diffusivity_time" calculation?
This is a similar calculation to omega_norm. It uses
the effective hydraulic diffusivity D, which is defined in
this case as the ratio of transmissivity to storativity:
D \equiv \frac{T}{S}
Value
Values of the constant represented by c.type for the given
parameters
Warnings Issued
In the case c.type='alpha', the
parameters S., T., and Rs. should
be passed; otherwise, values are assumed to ensure the
calculation does not fail, and the results are essentially meaningless.
Warnings will be issued if any necessary parameters are missing, indicating default values were used.
Author(s)
A. J. Barbour <andy.barbour@gmail.com>
See Also
alpha_constants, well_response, and
kitagawa-package for references and more background.
Other ConstantsCalculators:
alpha_constants(),
kitagawa-constants
Examples
# alpha
omega_constants() # default is alpha, but will give warnings about S., T., Rs.
omega_constants(T.=1,S.=1,Rs.=1) # 0, no warnings
omega_constants(1:10) # sequence, with warnings about S., T., Rs.
omega_constants(1:10,T.=1,S.=1,Rs.=1) # sequence, no warnings
# diffusivity time
omega_constants(c.type="diffusivity_time", D.=1) # 0, no warnings
omega_constants(c.type="diff", D.=1) # 0, no warnings (arg matching)
omega_constants(c.type="diff") # 0, warnings about S., T. because no D.
omega_constants(c.type="diff", S.=1) # 0, warnings about T. because no D. or S.