Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Short-term correction using the cylindrical heat source #44

Open
MassimoCimmino opened this issue Dec 10, 2019 · 4 comments
Open

Short-term correction using the cylindrical heat source #44

MassimoCimmino opened this issue Dec 10, 2019 · 4 comments
Assignees
Labels
Milestone

Comments

@MassimoCimmino
Copy link
Owner

This issue concerns the implementation of the infinite line source and cylindrical heat source solutions to correct the short-term response of geothermal bore fields.

@MassimoCimmino MassimoCimmino self-assigned this Dec 10, 2019
@MassimoCimmino MassimoCimmino added this to the v2.0.0 milestone Jan 8, 2021
@icupeiro
Copy link

Is this something that could be implemented as a method? I saw this issue and it reminded me of this piece of code from our previous works

def shortTermCorrection(time, gFunc, r_b, aSoi):
    
    def _CHS(u, Fo, p):
        CHS_integrand = 1./(u**2*pi**2)*(np.exp(-u**2*Fo) - 1.0) / (j1(u)**2 + y1(u)**2) * (j0(p*u)*y1(u) - j1(u)*y0(p*2))
        return CHS_integrand
    
    def _ILS(t, aSoi, dis):
        ILS = exp1(dis**2/(4*aSoi*t))
        return ILS
    
    for i in range(len(time)):
        ILS = _ILS(time[i], aSoi, r_b)
        CHS, err = quad(
            _CHS, 1e-12, 100., args=(aSoi*time[i]/r_b**2, 1.))
        gFunc[i] = gFunc[i] + 2*pi*CHS - 0.5*ILS

    return gFunc

@MassimoCimmino
Copy link
Owner Author

I tend to remember that the code presently in the branch issue44 is indeed from our previous work.

The development of the common interface for #33 will be a good opportunity to re-implement this into a method for the (still in development) g-function class.

@MassimoCimmino MassimoCimmino modified the milestones: v2.0.0, v2.1.0 May 20, 2021
@MassimoCimmino MassimoCimmino modified the milestones: v2.1.0, v2.2.0 Aug 26, 2021
@j-c-cook
Copy link
Contributor

j-c-cook commented Nov 12, 2021

Could the MIFT solution be applied to short-time steps, or is it still not applicable until the breaking time, t_b = 5*r_b**2/alpha?

Is there a specific reference that is going to be utilized to address this issue?

@MassimoCimmino
Copy link
Owner Author

The validity range of the MIFT solution is the same as for the uniform temperature condition. The breaking time t_b is related to the difference between heat emitted by a line source (at the center of the borehole) and heat emitted at the borehole wall. It is an estimation of the time it takes for the two source geometries to have matching temperatures at r=r_b.

The methodology in the above comments is inspired by Li et al. (2014) [1].

There is a distinction to make on the validity range of the g-function between the prediction of borehole wall temperatures (T_b) due to heat extracted at the borehole wall (Q_b), and the prediction of fluid temperatures (T_f) due to heat extracted from the fluid loop (Q_f). The correction using the CHS applies to the first case. The second case requires some transient heat transfer model for the inside of the boreholes.


[1] Li, M., Li, P., Chan, V. and Lai, A.C., 2014. Full-scale temperature response function (G-function) for heat transfer by borehole ground heat exchangers (GHEs) from sub-hour to decades. Applied Energy, 136, pp.197-205.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
Projects
None yet
Development

No branches or pull requests

3 participants