WIMS Library Update Project

International Reactor Physics Experiments (IRPhE)

Heavy water benchmarks:

·         MINOR Single rods of natural uranium metal in several square lattice pitches. In this series four different fuel rods were used with different fuel radii and with cladding made of different types of aluminum alloys.

·         SRLUR Single rods of natural uranium metal in aluminum cladding in four different hexagonal lattices.

·         NORAHW Single rods of 3% enriched UO₂ fuel in stainless steel cladding in five different square lattice pitches.

·         WLRX Clusters of 19 rods made of 1.1% enriched UO₂ fuel in aluminum cladding closed in single aluminum housing. Three different lattice pitches have buckling values reported.

·         DIMPSGHW Clusters of 90 rods made of 1.14% enriched UO₂ fuel in aluminum cladding closed inside pressure and calandria tubes. Benchmarks with five different types of coolant were performed. (Unreliable material data and two different set of buckling values reported).

HWL Benchmark Cases Details

All benchmarks were analysed for k_eff uncertainty and (depending on data) on uncertainties in material and dimensional data.

2.1 Processed benchmarks

NORA-RESR-EXP-001

CRIT-BUCK-RRATE

Date: between August 1960 and February 1963

Experiments were carried out in the NORA zero-power critical facility with a core of 3% enriched SS-clad fuel elements and heavy water moderator. For all lattices measured B² with experimental error is reported and for some also r₂₈, the ratio of neutron captures in ²³⁸U above Cd cut-off and below, and d²⁸, the ratio between fission rates in ²³⁸U and ²³⁵U. The d²⁸ was measured in different facility (the fuel elements were taken to JEEPNIK core for d²⁸ determination).

References:

1.        Sheets N3 to N7

2.        K. Bryhn-Ingebrigtsen, et al., Heavy Water Lattices: 2^nd Pannel, IAEA 1963, p.251-254

3.        S. O. Larvin, et al., Exponential and Critical Experiments Vol. II: Symposium, IAEA 1964, p.161-179

MINOR-RESR-EXP-001 to 004

SUB-BUCK

Date: between January and September 1963

MINOR subcritical exponential facility consisted of experimental tank 140 cm in diameter and 280 cm high filled with heavy water. Fuel rods inside the tank are suspended from above. Measurements were started with "reference lattices", completely filled with one type of fuel. In the next step the two zone measurements were performed. First set of measurements is considered in this benchmark with three different types of fuel (MINOR, DIORIT and AQUILON). For all lattices the B_m² was measured and reported with error interval.

The MINOR facility is very well documented with all necessary data needed to evaluate the subcritical exponential benchmarks.

References:

1.        Sheets CH1 to CH4

2.        R. W. Meier, et al., Exponential and Critical Experiments Vol. II: Symposium, IAEA 1964, p.59-83

3.        H. R. Lutz, et al., Exponential and Critical Experiments Vol. II: Symposium, IAEA 1964, p.85-108

PDP-RESR- EXP-001

CRIT-BUCK-RRATE

Date: before 1961

PDP facility at Savannah River Laboratory (SRL) was SS tank 16 ft 2 3/4 inch in diameter. It was filled with different single rods or clusters and the moderator height was adjusted to critical level. In the radial direction the pile could be reduced with adding Li-Al poison rods to the outer regions of tank.

Single rod configurations with lattice numbers 1-7, 1-8, 1-9 and 1-12 (SRL-UR-7 to SRL-UR-12) are processed in this batch. The same rods were also used for cluster experiments.

References:

1.        Sheets US1 to US4

2.        T. J. Hurley, et al., Nuclear Science and Engineering: 12, p.341-347 (1962)

LRX-RESR-EXP-001

CRIT-BUCK-SPEC-COEF-RRATE-POWDIS

Date:

WAPD Westinghouse Atomic Power Division, LRX Facility

The cluster consists of 19 fuel rods arranged in hexagonal geometry with rod to rod spacing 0.60". 19 rods make up one fuel assembly surrounded with one Al cluster tube. Fuel assemblies were studied in core tank (126" I.D., 139.6" depth) in three different square lattice pitches and two different enrichments.

Core configuration with 2% enrichment has no B² measurements.

DIMPLE-HWR-EXP-001

CRIT-BUCK-SPEC-RRATE

Date:1960 - 1961

Bz and Br bucklings were measured and Lu/Mn reaction rates. From these the delta28 and rho28 were determined. Also kinf value was measured.