Advanced Testing Method for Ground Thermal Conductivity
Abstract
A new method is developed that can quickly and more accurately determine the effective ground thermal conductivity (GTC) based on thermal response test (TRT) results. Ground thermal conductivity is an important parameter for sizing ground heat exchangers (GHEXs) used by geothermal heat pump systems. The conventional GTC test method usually requires a TRT for 48 hours with a very stable electric power supply throughout the entire test. In contrast, the new method reduces the required test time by 40%–60% or more, and it can determine GTC even with an unstable or intermittent power supply. Consequently, it can significantly reduce the cost of GTC testing and increase its use, which will enable optimal design of geothermal heat pump systems. Further, this new method provides more information about the thermal properties of the GHEX and the ground than previous techniques. It can verify the installation quality of GHEXs and has the potential, if developed, to characterize the heterogeneous thermal properties of the ground formation surrounding the GHEXs.
- Authors:
-
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Geothermal Design Center Inc., Asheville, NC (United States)
- Univ. of Tennessee, Knoxville, TN (United States)
- Publication Date:
- Research Org.:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Building Technologies Research and Integration Center (BTRIC)
- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- OSTI Identifier:
- 1354667
- Report Number(s):
- ORNL/TM-2017/208
ED2701000; CEED509; CRADA/NFE-16-06144
- DOE Contract Number:
- AC05-00OR22725
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 47 OTHER INSTRUMENTATION
Citation Formats
Liu, Xiaobing, Clemenzi, Rick, and Liu, Su. Advanced Testing Method for Ground Thermal Conductivity. United States: N. p., 2017.
Web. doi:10.2172/1354667.
Liu, Xiaobing, Clemenzi, Rick, & Liu, Su. Advanced Testing Method for Ground Thermal Conductivity. United States. doi:10.2172/1354667.
Liu, Xiaobing, Clemenzi, Rick, and Liu, Su. 2017.
"Advanced Testing Method for Ground Thermal Conductivity". United States.
doi:10.2172/1354667. https://www.osti.gov/servlets/purl/1354667.
@article{osti_1354667,
title = {Advanced Testing Method for Ground Thermal Conductivity},
author = {Liu, Xiaobing and Clemenzi, Rick and Liu, Su},
abstractNote = {A new method is developed that can quickly and more accurately determine the effective ground thermal conductivity (GTC) based on thermal response test (TRT) results. Ground thermal conductivity is an important parameter for sizing ground heat exchangers (GHEXs) used by geothermal heat pump systems. The conventional GTC test method usually requires a TRT for 48 hours with a very stable electric power supply throughout the entire test. In contrast, the new method reduces the required test time by 40%–60% or more, and it can determine GTC even with an unstable or intermittent power supply. Consequently, it can significantly reduce the cost of GTC testing and increase its use, which will enable optimal design of geothermal heat pump systems. Further, this new method provides more information about the thermal properties of the GHEX and the ground than previous techniques. It can verify the installation quality of GHEXs and has the potential, if developed, to characterize the heterogeneous thermal properties of the ground formation surrounding the GHEXs.},
doi = {10.2172/1354667},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 4
}
-
Reillex™ HPQ resin was developed by Los Alamos Laboratory and Reilly Industries Inc. in an effort to increase safety and process efficiency during the recovery and purification of plutonium. Ionac™ A-641, another strong base macroporous anion exchange resin used in the nuclear industry, was known to undergo a runaway reaction in hot nitric acid solutions. Because of this, an extensive amount of thermal analyses testing on the Reillex™ HPQ resin in SRNL was performed in 1999-2001 prior to use. A report on the thermal stability qualification of the Reillex™ HPQ resin in 8M (35%) and 12M (53%) HNO 3 wasmore »
-
Soil and rock classification according to thermal conductivity: Design of ground-coupled heat pump systems: Final report
This study establishes the ranges of values of thermal conductivity and thermal diffusivity of the various soils and rocks in the United States and provides this information in a form that can be used in the design of ground-coupled heat pump systems. It presents a simple classification system for use in the identification of soils and rocks by persons not trained in soil mechanics or petrology. This technical document is given practical application in a companion field manual for the identification and classification of thermal conductivity of the various soils and rocks that can be encountered in the United States.more »