Coupled THM analysis of the single-heater test at yucca mountain Page: 4 of 7
This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
trical-resistance tomography (ERT) were among the
techniques used to monitor the rock's water satura-
tion over time with the intent of estimating the
movement of steam condensate out of the system.
Section 2 of this paper presents a brief discussion of
these methods and results and of the temperature
history of the test. Section 3 presents a summary of
thermohydrologic (TH) and thermomechanical (TM)
simulations conducted for the SHT.
2 TEMPERATURE AND MOISTURE
One goal of the SHT was to raise rock temperature
near the heater to approximately 1400C and then to
monitor the predicted ensuing dry-out. Figure 2
shows the temperature history of a thermocouple lo-
cated near the heater midplane and within 0.25 m
(radially) of the heater. This figure shows that tem-
perature in the rock near the heater rose rapidly after
the heater was turned on, reaching 1000C at ap-
proximately 25 days after the start of heating. Tem-
perature then increased smoothly with heating,
reaching 1400C after 270 days of heating, when the
heater was turned off. Temperature in the rock near
the heater dropped quickly after the heater was
turned off, cooling to approximately 500C after
30 days of cooling (300 days from start of heating).
A few power outages occurred during the heating
phase of this test, causing the temperature to drop
rapidly during the outage, and then recover to near
pre-outage levels when power was restored. These
0 100 200 300
Figure 2. Temperature history of the SHT measured near the
heater. Sharp drop/recovery episodes are due to power outages.
Also shown are simulated temperatures calculated using the
NUFT TH model. (from Blair et al. 1998)
outages are evidenced by sharp drop/recovery epi-
sodes in the data.
Thermal neutron logging was used to monitor
moisture content in four boreholes during the SHT.
These are boreholes 15, 17, 22, and 23 in Figure 1.
They are oriented perpendicular to the heater and in
approximately the same plane as the ERT measure-
ment holes. The neutron-logging tool provides an es-
timate of the amount of water in a region within
about a 12-cm radius of the center of a borehole.
-5 -4 -3 -2 -1 0 1 2
Lateral distance (in)
3 4 5
-0.015-0.010-0.005 0.000 0.005 0.010 0.015
Volume fraction water
Figure 3. Moisture movement during the SHT, along a line perpendicular to and slightly below
the heater, as derived from neutron logging measurements
- - - case
Here’s what’s next.
This article can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Article.
Blair, S. C.; Buscheck, T. A.; Daily, W. D.; Lin, W. & Ramirez, A. L. Coupled THM analysis of the single-heater test at yucca mountain, article, January 25, 1999; Livermore, California. (digital.library.unt.edu/ark:/67531/metadc719035/m1/4/: accessed February 22, 2019), University of North Texas Libraries, Digital Library, digital.library.unt.edu; crediting UNT Libraries Government Documents Department.