Whose measurements these are
C. R. Toole set down how the C-core behaved under pressure and flow, surge by surge.
He wrote for the Atomic Energy Division of Phillips Petroleum Company, under contract to the U.S. Atomic Energy Commission, and his report of June 1964 gives the transients one by one in its appendix. The report of C. M. Condit, J. F. Scott and R. L. Johnson of 1967 gives the core’s constants.
- The author
- C. R. Toole
- Written for
- Phillips Petroleum Company, Atomic Energy Division, Idaho Falls, for the U.S. Atomic Energy Commission, contract AT(10-1)-205
- The report
- The Effects of Pressure and Flow on Room Temperature Power Excursions in Spert III. Report IDO-16918, June 1964.
- Where it is published
- The U.S. Department of Energy’s Office of Scientific and Technical Information: doi.org/10.2172/4042264
- The core’s constants
- C. M. Condit, J. F. Scott and R. L. Johnson, The Effects of Coolant Temperature and Initial Power Level on the Excursion Behavior of a Highly Enriched Plate Core in Spert III: Experiment and Analysis. Report IDO-17138, 1967: doi.org/10.2172/4389198
What happened
126 surges, 111 of them used, at room temperature, under pressure and flow.
Some began with the water still, at 0 to 2,500 psig. Others began at 230 psig with water flowing at 200 to 20,000 gallons a minute. Each time 0.412 to 1.305 dollars of reactivity went in, and the power climbed.
How hot does a fuel plate get when the power surges and the water beside it begins to boil? The C-core tests put that question under pressure and under flow, so the answer could be read against both.
Toole recorded each transient’s peak power, the energy released to the peak and the rise of the hottest plate. This page is about a model fitted on all 111 and compared with each tenth of them left out in turn.
It is the second SPERT III core the verifier serves. The first, the oxide E-core of the 1969 report, has a page of its own.
What the model did
Fitted on all 111 transients and compared with each tenth left out, the model gives peak power within 10.4 percent RMS.
The model computes the reactor’s power, the energy it releases and the temperature of the hottest plate through its first maximum: six groups of delayed neutrons, three nodes of plate meat, cladding, the film of water, the bulk water and vapour, the plates’ feedback lagging their temperature by 5.69 milliseconds and the film thinning as the flow rises.
It is fitted on all 111 transients of the report: ten constants. Compared with each tenth left out of the fit in turn, it gives peak power within 10.4 percent RMS, energy to the peak within 17.2, and the hottest plate’s rise within 12.3 at peak power and 11.3 at its first maximum.
The largest gap is high flow. Left out, at 5,000 to 20,000 gpm the plate maximum reads 24.6 percent RMS, 12.9 without transient 03618, against a repeat scatter of 5.5; at 200 to 2,040 gpm, 13.6 on 3 transients.
Asked for a surge of 1.25 dollars at 2,500 psig with the water still, from 25 °C, it gives a peak of 713.6 megawatts at 0.209 seconds with 16.07 megawatt-seconds released on the way up. The hottest plate then rises 365.8 K to its first maximum, where the run reaches the end the card declares, PastPlateTemperatureMaximum. Past saturation the hot spot boils, and every step there carries its flag with the limit, the value and the extent: FLAG_HOT_SPOT_BOILING, limit 627.06 K, value 663.93 K, 36.87 K past it at the last step. The run comes back with the proof c5246a5c…8deae3, 96 characters of SHA-384, and the signature of the verifier’s answer key.
A dataset of 196 sealed runs of this model, made on engine 0.15.0, is on Hugging Face.
Comparedwith measurement
Where it stops
Compared from still water to 20,000 gpm. Past that it computes with the same equations. A run ends at the hottest plate’s first maximum.
In the verifier’s own words: “Past what a model was compared with, it keeps going with the same equations and flags every step. It stops only at a physical limit, or where its equations, constants or tables no longer hold, and it names the reason.”
What it was compared on
- Reactivity of 0.412 to 1.305 dollars with no flow at 0 to 2,500 psig.
- 0.870 to 1.305 dollars at 230 psig with 200 to 20,000 gpm.
- Water at 21 to 36 °C at the start.
- Three things about each surge: peak power, energy to the peak and the rise of the hottest plate.
Past that, and what its own description says of itself
- Any reactivity above zero, any flow, and any start of liquid water from 611.657 Pa to 22.064 MPa, with the same equations.
- A run ends at the first maximum of the hot-spot plate temperature after the power peak (
PastPlateTemperatureMaximum). - It refuses zero or less reactivity (
ReactivityNotPositive), a start that is not liquid water (InitialTemperatureNotLiquidWater), a pressure outside the steam tables (PressureOutsideSteamTables), a flow below zero (NegativeFlow) and a reactivity changed during a run (ReactivityChangedDuringRun).
For the reader who wants every number
In the verifier’s own words.
Everything above is this page’s telling. What follows is the verifier’s own, exact and whole: the spec sheet of the model energy/reactor_spert3_ccore as version 0.15.0 serves it in its description, in its six parts, with its word for how it stands against measurement: compared with measurement. The verifier’s current description is the one to trust. Where it says card it means a model, and where it says refuses it names the reason a run stops.
What it computes
Power burst of the SPERT III C-core test reactor with subcooled boiling and void: point kinetics with six delayed groups and three nodes of plate meat, cladding, film, bulk water and vapour, the plates’ feedback lagging their temperature by 5.69 ms and the film thinning with the flow: power, energy released and the hot-spot plate temperature through its first maximum.
Range
Range: compared at 0.412 to 1.305 dollars with no flow at 0 to 2500 psig, and 0.870 to 1.305 dollars at 230 psig with 200 to 20,000 gpm, from 21 to 36 degC; computes any reactivity above zero, any flow, and any start of liquid water from 611.657 Pa to 22.064 MPa with the same equations.
Fitted on
Fitted on the 111 transients of IDO-16918, every one read when the structure was chosen: ten constants and the 1.88020 s at which a plate maximum still rising is read.
Compared with
Compared with each tenth of the 111 left out of the fit in turn: peak power within 10.4 percent RMS, energy to the peak 17.2, the hot-spot plate rise at peak power 12.3 and at its first maximum 11.3; at 1000 to 2500 psig and 11.5 ms or less peak power 8.6.
Gap
Gap: left out, at 5000 to 20,000 gpm the plate maximum reads 24.6 percent RMS (12.9 without transient 03618), against a repeat scatter of 5.5; at 200 to 2040 gpm 13.6 (3 transients), and energy at 1000 to 2500 psig and 11.5 ms or less 10.7.
Refuses
Refuses zero or less reactivity (ReactivityNotPositive), a start that is not liquid water (InitialTemperatureNotLiquidWater), a pressure outside the steam tables (PressureOutsideSteamTables), a flow below zero (NegativeFlow) and a reactivity changed during a run (ReactivityChangedDuringRun); a run ends at the first maximum of the hot-spot plate temperature after the power peak (PastPlateTemperatureMaximum).
Hand this one to your agent.
https://mcp.zerotrustphysics.com/mcp
Something to paste
Connect to https://
Give it this page too.
What it will find
This model’s spec sheet: what it computes, its range, what it was fitted on, what it was compared with and how close it came, its gap and what it refuses.