Estimation of groundwater flow from temperature monitoring in a borehole heat exchanger during a thermal response test

2017 ◽  
Vol 26 (3) ◽  
pp. 853-867 ◽  
Author(s):  
Mayumi Yoshioka ◽  
Shinichi Takakura ◽  
Youhei Uchida
Keyword(s):  
Heat Exchanger ◽  
Groundwater Flow ◽  
Thermal Response ◽  
Temperature Monitoring ◽  
Thermal Response Test ◽  
Borehole Heat Exchanger ◽  
Response Test

scholarly journals Comparison of Four Methods for Borehole Heat Exchanger Sizing Subject to Thermal Response Test Parameter Estimation

Energies ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 4067 ◽  
Author(s):  
Xuedan Zhang ◽  
Tiantian Zhang ◽  
Bingxi Li ◽  
Yiqiang Jiang
Keyword(s):  
Parameter Estimation ◽  
Heat Exchanger ◽  
Thermal Response ◽  
Data Interpretation ◽  
Relative Difference ◽  
Fluid Temperature ◽  
Thermal Response Test ◽  
Borehole Heat Exchanger ◽  
Response Test ◽  
The Impact

The impact of different parameter estimation results on the design length of a borehole heat exchanger has received very little attention. This paper provides an in-depth investigation of this problem, together with a full presentation of six data interpretation models and a comprehensive comparison of four representative sizing methods and their inter models. Six heat transfer models were employed to interpret the same thermal response test data set. It was found that the estimated parameters varied with the data interpretation model. The relative difference in borehole thermal resistance reached 34.4%, and this value was 11.9% for soil thermal conductivity. The resulting parameter estimation results were used to simulate mean fluid temperature for a single borehole and then to determine the borehole length for a large bore field. The variations in these two correlated parameters caused about 15% and 5% relative difference in mean fluid temperature in the beginning and at the end of the simulation period, respectively. For computing the borehole design length, software-based methods were more sensitive to the influence of parameter estimation results than simple equation-based methods. It is expected that these comparisons will be beneficial to anyone involved in the design of ground-coupled heat pump systems.

Evaluation of thermal short-circuiting and influence on thermal response test for borehole heat exchanger

Geothermics ◽  
2014 ◽  
Vol 50 ◽  
pp. 136-147 ◽  
Author(s):  
Yong Li ◽  
Jinfeng Mao ◽  
Shibin Geng ◽  
Xu Han ◽  
Hua Zhang
Keyword(s):  
Heat Exchanger ◽  
Thermal Response ◽  
Thermal Response Test ◽  
Borehole Heat Exchanger ◽  
Response Test

Ground thermal conductivity estimation using the thermal response test with a horizontal ground heat exchanger

Geothermics ◽  
2021 ◽  
Vol 96 ◽  
pp. 102213
Author(s):  
Esteban Urresta ◽  
Marcelo Moya ◽  
Carlos Campana ◽  
Carlos Cruz
Keyword(s):  
Thermal Conductivity ◽  
Heat Exchanger ◽  
Thermal Response ◽  
Ground Heat Exchanger ◽  
Thermal Response Test ◽  
Response Test

Thermal response test analysis for U-pipe vertical borehole heat exchangers under groundwater flow conditions

2021 ◽  
Vol 165 ◽  
pp. 391-404
Author(s):  
Teresa Magraner ◽  
Álvaro Montero ◽  
Antonio Cazorla-Marín ◽  
Carla Montagud-Montalvá ◽  
Julio Martos
Keyword(s):  
Groundwater Flow ◽  
Heat Exchangers ◽  
Thermal Response ◽  
Thermal Response Test ◽  
Flow Conditions ◽  
Test Analysis ◽  
Response Test ◽  
Borehole Heat Exchangers ◽  
Vertical Borehole

scholarly journals Method of Averaging the Effective Thermal Conductivity Based on Thermal Response Tests of Borehole Heat Exchangers

Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3737
Author(s):  
Aneta Sapińska-Śliwa ◽  
Tomasz Sliwa ◽  
Kazimierz Twardowski ◽  
Krzysztof Szymski ◽  
Andrzej Gonet ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Heat Exchanger ◽  
Effective Thermal Conductivity ◽  
Heat Exchangers ◽  
Thermal Response ◽  
Method Of Averaging ◽  
Thermal Response Test ◽  
Borehole Heat Exchanger ◽  
Measurement Results ◽  
Borehole Heat Exchangers

This work concerns borehole heat exchangers and their testing using apparatus for thermal response tests. In the theoretical part of the article, an equation was derived from the known equation of heat flow, on which the interpretation of the thermal response test was based. The practical part presents the results of several measurements taken in the AGH Laboratory of Geoenergetics. They were aimed at examining the potential heat exchange capacity between the heat carrier and rock mass. Measurement results in the form of graphs are shown in relation to the examined, briefly described wells. Result analysis made it possible to draw conclusions regarding the interpretation of the thermal response test. The method of averaging the measurement results was subjected to further study. The measuring apparatus recorded data at a frequency of one second, however such accuracy was too large to be analyzed efficiently. Therefore, an average of every 1 min, every 10 min, and every 60 min was proposed. The conclusions stemming from the differences in the values of effective thermal conductivity in the borehole heat exchanger, resulting from different data averaging, were described. In the case of three borehole heat exchangers, ground properties were identical. The effective thermal conductivity λeff was shown to depend on various borehole heat exchanger (BHE) designs, heat carrier flow geometry, and grout parameters. It is important to consider the position of the pipes relative to each other. As shown in the charts, the best (the highest) effective thermal conductivity λeff occurred in BHE-1 with a coaxial construction. At the same time, this value was closest to the theoretical value of thermal conductivity of rocks λ, determined on the basis of literature. The standard deviation and the coefficient of variation confirmed that the effective thermal conductivity λeff, calculated for different time intervals, showed little variation in value. The values of effective thermal conductivity λeff for each time interval for the same borehole exchanger were similar in value. The lowest values of effective thermal conductivity λeff most often appeared for analysis with averaging every 60 min, and the highest—for analysis with averaging every 1 min. For safety reasons, when designing (number of BHEs), safer values should be taken for analysis, i.e., lower, averaging every 60 min.

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