TEMPERATURE DISTRIBUTION MODERATOR AND REFLECTOR REACTOR CORE. EXPERIMENTAL GAS COOLED REACTOR

Technical Report · Mon Apr 25 04:00:00 EDT 1960

DOI:https://doi.org/10.2172/4719545· OSTI ID:4719545

Cheng, F

A study was made to determine the coolant flow required to prevent the temperature of the graphite moderator and reflector blocks from exceeding 1100 deg F at full-power operating conditions. The temperature distribution in the graphite blocks was also determined. Tha moderator was primarily cooled by coolant flowing in the 1/8-inch annulus formed by the fuel-assembly sleeves and the fuel-channel holes in the moderator blocks. Coolant flow in the controlrod channels and in the experimental-tube coolant annuli also cooled the moderator, and this effect was considered in setting moderator-annulus coolant flow. The coolant flows required for each of four zones in the reactor core were determined. The total moderator-annulus coolant flow (excluding 16 unfueled channels) was 15,200 lb/hr. The moderator-block temperature distributions for fullpower reactor operation after 20 years of operation are given. The maximum temperature (1100 deg F average over the cross section) occurred near the top of the graphite block. The temperature in the majority of the graphite columns varied from 600 to 1000 deg F over the lower half of the column and from 1000 to 1100 deg F over the top half of the column. The maximum graphite surface temperature was less than 1100 deg F. Reflector-block temperatures (average over the cross section) did not exceed 1060 deg F. The axial temperature distribution was approximately linear over the length of the column and varied from 560 deg F at the bottom to 1050 deg F at the top. Axial temperature distribution for each reflector column is also shown. The maximum temperature difference over a column cross section was less than 150 deg F for normal full-power operation. A maximum temperature difference of 450 deg F over a column cross section was calculated for the condition in which one of the fuel channels has 3500 lb/hr of coolant with no fuel assemblies. The time required for this temperature difference to develop in the column is about 10 minutes after start of unloading. (auth)

• Research Organization: Allis-Chalmers Mfg. Co. Atomic Energy Div., Washington, D.C.
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-017550
• OSTI ID: 4719545
• Report Number(s): TID-18098; EGCR-STUDY-II-226
• Country of Publication: United States
• Language: English

Related Subjects

CONTROL ELEMENTS
DISTRIBUTION
EGCR
FUEL ELEMENTS
GAS COOLANT
GAS FLOW
GRAPHITE MODERATOR
HIGH TEMPERATURE
POWER PLANTS
REACTOR CORE
REACTOR TECHNOLOGY
REACTORS
REFLECTORS
SURFACES
TEMPERATURE
ZONES