BURNOUT CONDITIONS FOR NONUNIFORMLY HEATED ROD IN ANNULAR GEOMETRY. WATER AT 1000 PSIA

Technical Report · Sat Jun 01 04:00:00 EDT 1963

DOI:https://doi.org/10.2172/4703410· OSTI ID:4703410

Janssen, E.; Kervinen, J. A.

Tests were run to determine the burnout conditions for a nonuniformly heated rod in an annular geometry. Two special electrically heated rods were used; the cosine rod, which gave an approximate cosine axial heat flux distribution; and the truncated cosine rod, identical to the cosine, except for one end cut short. The rod to be tested was placed in a circular tube test section to form the annular flow path for the water coolant. Only the rod was heated; the outer surface (tube) was essentially adiabatic. Orientation was vertical, with flow upward. The tests were run at the following conditions: rod OD, C.540 inch; tube ID, 0.875 inch; hydraulic diameter, 0.335 inch; heated length of cosine rod, 108 inches; heated length of truncated cosine, 91 inches; pressure, 1000 psia; flow rate, 0.84 x 10/sup 6/ to 1.40 x 10/sup 6/ lb/hr-ft/sup 2/; and steam quality at exit, 12 to 35%. For each flow and iniet subcooling, the electrical power was increased until burnout was reached, thus establishing a burnout condition. Each nonuniform rod was instrumented with thermocouples in the region of anticipated burnout. The local heat flux and local quality at each position at which a thermocouple indicated a temperature rise, were determined for each burnout run. The local heat flux at burnout was plotted versus the local quality at burnout, for the two nonuniform rods. The uniform rod burnout correlation was superposed for comparison. The nonuniform rod data points averaged from 9 to 20% low. The magnitude of this deviation is considered small, and of the same order as that for the uniform rod data upon which the correlation was originally based. It was concluded that the uniform rod burnout correlation can be used to predict burnout for cosine heat flux distribution. It is tacit in this conclusion that burnout depends only on local conditions of quality and flow. A method for predicting burnout for a nonuniform heat flux distribution was developed and applied to all the cosine and truncated cosine rod data. The predicted average heat flux at burnout is within +11%, --2.5% of the measured average heat flux. The method predicts the most probable position at which burnout will occur, and accurately predicts the power level at which burnout will occur. (auth)

• Research Organization: General Electric Co. Atomic Power Equipment Dept., San Jose, Calif.
• NSA Number: NSA-17-030659
• OSTI ID: 4703410
• Report Number(s): GEAP-3755
• Country of Publication: United States
• Language: English

Related Subjects

BURNOUT
CONFIGURATION
COOLING
DIAGRAMS
DISTRIBUTION
ELECTRICITY
ENGINEERING AND EQUIPMENT
ERRORS
FLUID FLOW
HEATING
HYDRAULICS
LABORATORY EQUIPMENT
MEASURED VALUES
PRESSURE
QUANTITATIVE ANALYSIS
RODS
STEAM
STEAM QUALITY
SUBCOOLING
TEMPERATURE
THERMOCOUPLES
TUBES
VARIATIONS
VELOCITY
WATER