SINBAD ABSTRACT NEA-1517/103
NESDIP-2 Benchmark Experiment (ASPIS)
1. Name of Experiment:
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NESDIP-2 Benchmark Experiment (ASPIS)
2. Purpose and Phenomena Tested:
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Neutron transport in a shield simulating the radial shield of a PWR,
including the cavity region and the backing shield.
3. Description of the Source and Experimental Configuration:
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The source is a fission plate constructed of 93% enriched uranium aluminium
alloy driven by a thermal flux from the extended graphite reflector of the
NESTOR reactor. The effective radius of the fission plate is 56 cm and the
thickness 2 mm. The energy spectrum of the source is that of neutrons
emitted from the fission of U-235. The absolute source strength is
determined by fission product counting and the spatial distribution via
detailed low energy flux mapping with activation detectors.
The shield simulates the radial shield of a PWR and consists of 12.1 cm of
water, a 6.3 cm stainless steel plate simulating the thermal shield,
13.2 cm of water, five mild steel plates giving a thickness of 22.8 cm to
simulate the pressure vessel, a 29.4 cm cavity region and a backing shield
of aluminium, water and mild steel.
4. Measurement System and Uncertainties:
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The detectors used were:
Typical Counting Systematic
Detector Diameter Thickness Mass System Absolute
(mm) (mm) (g) Calibration
(uncertainty)
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Rh103(n,n') 12.7 0.015 0.20 NaI 3.0%
In115(n,n') 38 1.63 12.79 GeLi 1.9%
detector
S32(n,p) 38.1 2.41 5 Plastic 5.0%
Pressed Pellet Scintillator
S32(n,p) 51 5.6 22 Plastic 5.0%
Cast Pellet Scintillator
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5. Description of Results and Analysis:
-----------------------------------
Measurements of the reaction rates S32(n,p)P32, In115(n,n')In115m and
Rh103(n,n')Rh103m were made in activation foils between the mild steel
plates (reactor pressure vessel region) and in the cavity whilst
Rh103(n,n')Rh103m measurements were also made in the water regions.
In addition, during all irradiations of activation detectors within the
shields, three sulphur pellets were placed in locations at the centre of
the front face of the fission plate to monitor its run-to-run power via
the S32(n,p)P32 reaction.
The results were corrected for the background responses due to the NESTOR
core. Using the hydrogen filled proportional counters of the TNS system
the correction was found to be around 2(+/-1)% in the RPV and cavity and
1(+/-1)% in the water cell.
Calculations were carried out with the Monte Carlo codes McBEND Version 7B
[1], [5].
More recently the MCNP5 models were prepared and are also incuded in this
compilation [8].
6. Quality assessment:
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The NESDIP-2 experiment is ranked as experiment of low benchmark quality
because of the missing details on the absolute calibration.
Moreover, additional experimental information would be advisable on:
- detectors arrangement,
- water tanks bowing,
- effect of the NESTOR reflector,
- background subtraction.
7. Author/Organizer
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Experiment and analysis:
A. Avery, S. Bell, I.J. Curl, G.A. Wright
AEA Technology
WINFRITH, Dorchester
Dorset DT2 8DH
UK
Compiler of data for Sinbad:
I. Kodeli
OECD/NEA, 12 bd des Iles, 92130 Issy les Moulineaux, France
Reviewer of compiled data:
A. Avery,
Reactor Physics, Shielding and Criticality Department, AEA Technology
WINFRITH, Dorchester
Dorset DT2 8DH
UK
Quality assessment:
A. Milocco,
Universita' di Milano-Bicocca, piazza della Scienza 3, Milano, Italy
8. Availability:
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Unrestricted
9. References:
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[1] A. Avery, AEA-RS-5629, private communication
[2] M. J. Armishaw, J. Butler, M. D. Carter, I. J. Curl, A. K. McCracken,
A Transportable Neutron Spectrometer (TNS) for Radiological
Applications, AEEW-M2365 (1986).
[3] I. J. Curl, CRISP - A Computer Code to Define Fission Plate Source
Profiles, RPD/IJC/934.
[4] P. C. Miller, A Review of LWR Pressure Vessel Dosimetry and Associated
Shielding Studies, Proceedings, 7th International Conference on Radiation
Shielding, Sept. 12-16, 1988, Bournemouth, UK, Vol.1, p.37.
[5] G. A. Wright, A. Avery, M. J. Grimstone, H. F. Locke, S. Newbon,
Benchmarking of the JEFF2.2 Data Library for Shielding Applications,
Proceedings, 8th International Conference on Radiation Shielding,
April 24-28, 1994, Arlington, Texas, U.S.A., vol.2, p.816.
[6] A. Avery, A review of Shielding Benchmarks for the Validation of
JEF 2.2, JEF/DOC-666, Nuclear Energy Agency, Paris, France, 1997.
[7] M.D. Carter, I.J. Curl, NESTOR Shielding and Dosimetry Improvement
Programme. The ASPIS-PCA Slab Geometry Benchmarks. Blind Test
Edition. UKAEA Winfrith, June 1986
[8] A. Milocco, Quality Assessment of Evaluated Experiments NESDIP-2,
NESDIP-3,JANUS-1 and JANUS-8, IJS-DP-11195, June 2012.
10. Data and Format:
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Filename Size[bytes] Content
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1 nes2-abs.htm 8.007 This information file
2 nes2-exp.htm 23.538 Description of the experiment
3 NESD2-1V.TIF 78.510 Figure 1: Cross-section of the shield (high quality)
4 NESD2-2V.TIF 21.372 Figure 2: Measurement locations (high quality)
5 NESD2-3V.TIF 116.100 Figure 3: Schematic diagram of fission plate (high quality)
6 NESD2-4V.TIF 13.786 Figure 4: Fuel element (high quality)
7 NESD2-5V.TIF 80.340 Figure 5: Disposition of fuel in fission plate (high quality)
8 NESD2-6S.TIF 648.635 Figure 6: Positioning of the fission plate (high quality)
9 NESD2-1V.gif 26.444 Figure 1: Cross-section of the shield (preview)
10 NESD2-2V.gif 14.414 Figure 2: Measurement locations (preview)
11 NESD2-3V.gif 23.306 Figure 3: Schematic diagram of fission plate (preview)
12 NESD2-4V.gif 6.995 Figure 4: Fuel element (preview)
13 NESD2-5V.gif 23.589 Figure 5: Disposition of fuel in fission plate (preview)
14 NESD2-6S.gif 21.107 Figure 6: Positioning of the fission plate (preview)
15 NESDIP2.pdf 886.561 Reference
16 aspis_0.pdf 608.178 Reference
17 jef-476.pdf 578.980 Reference
18 jef-666.pdf 750.902 Reference
19 ML010400029.pdf Reference
20 QualityAssessment.pdf 458.860 Document on quality assessment for NESDIP-2 experiment
21 N2Rh.i 15.250 MCNPX(5) input model with Rhodium detector
22 N2S.i 14.868 MCNPX(5) input model with Sulphur detector
23 N2S.i 14.767 MCNPX(5) input model with Indium detector
Tables:
One table (1) of axial dimensions and (2) of material specifications, one
table (3) describing the source distribution, and 3 tables (4-6) of the
measured reaction rates.
Figures describing the geometry of the experiment are included in
TIFF4 image format and GIF (preview).
SINBAD Benchmark Generation Date: 1997
SINBAD Benchmark Last Update: 1/2013