May 2006, CMS Users Group, May 2006, CMS Users Group, Minneapolis, MNMinneapolis, MN 11
Eigenvalue Trends at BVPS-1 and BVPS-2
Kenneth NaugleFirst Energy Nuclear Operating Company
A-GO-276 S. Main St.
Akron, OH [email protected]
May 2006, CMS Users Group, Minneapolis, MN
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Computer Codes
CASMO-4, v2.05.10
CMSLINK, v1.22.00
INTERPIN, v3.03
SIMULATE-3, v6.07.17 (FENOC build)
XIMAGE tool, v2.0.36
May 2006, CMS Users Group, Minneapolis, MN
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BVPS Reactivity Issue
Recent experience with EOC Keff & Critical boron indicates an adverse trend for BVPS-2 (and BVPS-1 to a lesser extent)Increasing excess reactivity towards EOCCurrently ~+300 pcm at BVPS-1 EOC17. BVPS-2 ~+400 pcm MOC12. Project >+500 pcm at EOC12.
May 2006, CMS Users Group, Minneapolis, MN
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History
Both units, calorimetric using Feed Venturi until 2001Switch to LEFM measurement and 1.4% power uprate after 10/2001.Unit 2 did not see a power increase (OE12686) and concluded BVPS-2 was running at ~1.5% overpower prior to 2001.Core model did not confirm overpower condition.
May 2006, CMS Users Group, Minneapolis, MN
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BVPS-1 EOC Critical Boron
• BVPS-1 current trends indicate a relatively steady trend in EOC reactivity as represented by the EOC ΔBoron
• Note 1.4% power uprate (improved calorimetric, Cycle 15)
• There may be a trend from cycle 15 on.
• Current EOC Keff ≈ 0.9970
May 2006, CMS Users Group, Minneapolis, MN
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• Current data indicates an increasing trend in EOC surplus reactivity at BVPS-2 as represented by the rising EOC ΔBoron
• Note 1.4% power uprate (implementation of improved calorimetric mid-Cycle 9)
• Current EOC Keff ≈ 0.9961
BVPS-2 EOC Critical Boron
May 2006, CMS Users Group, Minneapolis, MN
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BVPS-1 Cycle K-eff Trends
May 2006, CMS Users Group, Minneapolis, MN
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BVPS-2 Cycle K-eff Trend
May 2006, CMS Users Group, Minneapolis, MN
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BV2C12 Eigenvalue Comparison
May 2006, CMS Users Group, Minneapolis, MN
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Issues
Vendor code agrees with SIMULATE-3 results.System experts have not identified any problem with current calorimetric.The BVPS-2 system is the superior system (Check+ LEFM). BVPS-1 has the older “Check”system.Future power uprates will add additional 7.8% power at both units
May 2006, CMS Users Group, Minneapolis, MN
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BVPS-2 EOC Critical Boron at Constant Power
May 2006, CMS Users Group, Minneapolis, MN
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Conclusions
Current core models show a gradual reduction in critical Keff with increasing core exposure.Concern at BVPS-2 is to avoid Δρ approaching T.S. limit of 1%.BVPS-2 model at constant power is consistent, but Δρ seems high.Future power uprates are a wildcard, effect must be carefully watched.