W’s AP600 &AP1000 by T. G. Theofanous

In-Vessel Retention Loviisa VVER-440 first (1979) Westinghouse's AP-600 (1987) FRR’ 17 Korean KNGR and AP1400 (1994) Westinghouse’s AP-1000 (2004) NUPEC’s BWR’s (2000) The AP-600 work took three years it involved ~10 FTE’s and was finalized with 17 experts

AP-600 The final bounding state

Phenomena of In-Vessel Melt Retention

Framework for Addressing IVR Thermal Regime

Framework for Addressing IVR FCI Regime

Research to Support Assessment of IVR Thermal Loads

The Basic Geometry and Nomenclature of In-vessel Retention in the Long-term, Natural Convection-Dominated, Thermal Regime

Schematic of the Physical Model Used to Quantify Emergency Energy Partition, and Thermal Loads in the Long-term, Natural Convection Thermal Regime. Also Shown is the Nomenclature used in the Formulation of the Mathematical Model.

Schematic of the ACOPO facility

The ACOPO facility

The heat flux distribution on the lower boundary of a naturally convecting hemispherical pool ACOPO

Nusselt number dependence on external Rayleigh number

Heat Flux at the Pool Upper Corner (Churchill-Chu, 1975) ACOPO (1998)

The oxides pool Nusselt number, as a function of the Rayleigh number and the “fill” fraction, H 0 =R

Nu p;up /Nu p as function of Ra 0 and H 0 =R

Nu m /Nu up as function of Ra q, H m /R, and G G is a new dimensionless group reflecting materials properties. H m /R = 0.1 H m /R = 0.2 H m /R = 0.3 H m /R = 0.4 Lines within each H m /R group correspond to emissivity (bottom to top) 0.45; 0.55; 0.65; 0.75

Research to Support Assessment of IVR Heat Removal Capability

Schematic of the ULPU facility: Configuration III

The ULPU facility

A temperature transient (local microthermocouple response) associated with boiling crisis

Critical heat flux as a function of angular position on a large scale hemispherical surface ULPU-2000

Schematic of the ULPU facility: Configuration IV

New Configuration IV CHF results (data points), relative to curren (AP600) technology ULPU-2000

Schematic of the mini-ULPU facility

The mini-ULPU Experiment

The Critical Heat Flux Data Obtained in mini-ULPU Contact Frequency, Hz ----□---- Copper ----  ---- Steel Both Surfaces are Well-Wetted Critical Heat Flux, kW/m 2

 200  m  100  m 130  m Glass Heater 20x40 mm Constant Flux, Verified Infinite Flat Plate Behavior 100 nm Ti Flash X-Ray (5 ns) Film High-speed IR 2kHz (5kHz) High-speed video  100  m Seeing is believing The BETA Experiment

The Critical Heat Flux Data Obtained in BETA CHF K-Z = 1.2 MW/m 2

Generalization In-Vessel Retention for Larger Power Reactors

The Coolability Region of an AP600 reactor for different cooling options and metal layer emissivity Lines in each group correspond to fraction of Zr taken to be oxidized (0.2; 0.4; 0.6; 0.8) Pool Boiling  = 0.45 N/C Boiling  = 0.45 N/C Boiling  = 0.8

The Coolability Region of an GE-BWR reactor for different cooling options and metal layer emissivity Lines in each group correspond to fraction of Zr taken to be oxidized (0.2; 0.4; 0.6; 0.8) Pool Boiling  = 0.45 N/C Boiling  = 0.45 N/C Boiling  = 0.8 GE-BWR

The Coolability Region of an W-PWR reactor for different cooling options and metal layer emissivity Lines in each group correspond to fraction of Zr taken to be oxidized (0.2; 0.4; 0.6; 0.8) Pool Boiling  = 0.45 N/C Boiling  = 0.45 N/C Boiling  = 0.8 W-PWR

The Coolability Region of an Evolutionary PWR reactor for different cooling options and metal layer emissivity Lines in each group correspond to fraction of Zr taken to be oxidized (0.2; 0.4; 0.6; 0.8) Pool Boiling  = 0.45 N/C Boiling  = 0.45 N/C Boiling  = 0.8 E-PWR

Making the case for AP1000

AP1000 IVR Thermal Margin Estimates based on AP600 Technology Thermal Load AP600 AP1000 Coolability Limit (CHF)

ULPU-V as Simulation Tool of AP1000 Full Length; with Heat Flux Shaping we have Full Scale Simulation Complete Natural Circulation Path of AP1000 Represented as 1/84-Slice and Matched Resistance (Flow Areas and Geometry) as specified by Westinghouse designers Special Investigations on Surface Effects: Paints, Coatings, Deposits (boric acid in water), etc.

ULPU-V: Three Baffle Configurations

AP1000 water inlet geometry

ULPU-V Steam Outlet

ULPU-2400 Configuration V 1152 heaters (power control) Magnetic Flowmeter 72 thermocouples 7 pressure transducers Flow visualization

ULPU-V Reference Data for AP1000 IVR Conditions