Tikhonov regularization stabilizes multi-parameter estimation of geothermal heat exchangers

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Author(s)

Detail(s)

Original languageEnglish
Article number125479
Journal / PublicationEnergy
Volume262
Issue numberPart B
Online published20 Sept 2022
Publication statusPublished - 1 Jan 2023

Abstract

Parameter estimation from thermal response tests (TRTs) becomes unreliable when testing time reduces or the number of estimated parameters increases because of low identifiability and ill-posed mathematical feature. To overcome this challenge, this paper reports an inversion algorithm integrating a short-time temperature response model and the zero-order Tikhonov regularization strategy. We applied the algorithm to a reference sandbox dataset and examined four scenarios: simultaneous estimation of four, five, six, or seven parameters of U-shaped geothermal heat exchangers. The preliminary results indicate that the Tikhonov regularization can improve the accuracy and precision of the nonlinear multi-parameter estimation of ground heat exchangers for both long (>48 h) and short (<48 h) tests. The improved performance is contributed to the short-time model, which enables the short-time high-sensitivity data to be useable, and the regularization, which stabilizes the iterative optimization-solving procedure.

Research Area(s)

  • Ground heat exchangers, Parameter estimation, Short-time G function, Thermal response tests, Tikhonov regularization

Citation Format(s)

Tikhonov regularization stabilizes multi-parameter estimation of geothermal heat exchangers. / Du, Yufang; Li, Min; Li, Yong et al.
In: Energy, Vol. 262, No. Part B, 125479, 01.01.2023.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review