E-CodeNeutron diffusion: critical size, flux — a TI-84 Plus CE program
NEUTDIF is a TI-BASIC program for the TI-84 Plus CE. One-group bare reactor: diffusion length, k-infinity, material buckling, critical size (slab, sphere or cylinder) with extrapolation distance, flux shape and peaking.
What it asks for and what it shows
It asks for 4 values at its prompts, after you pick option 1 from its menu. In the example below it shows L CM, KINF, BM2, SIZE CM, FLUX, PK/AVG.
Example run
One of its oracle test cases: “slab”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Menu | option 1 |
| Input 1 | 1 |
| Input 2 | 0.02 |
| Input 3 | 0.03 |
| Input 4 | 5 |
| The screen shows | |
L CM= | 7.071067812 |
KINF= | 1.5 |
BM2= | 0.01 |
SIZE CM= | 27.15592654 |
FLUX= | 0.8775825619 |
PK/AVG= | 1.570796327 |
How it's checked
6 test cases, each checked against an independent method. Replayed key by key on a virtual TI-84 Plus CE, they make 43 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-84 Plus CE calculator and pick “Neutron diffusion: critical size, flux” (NEUTDIF).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
Related programs
- Four-factor formula and criticality
- Radioactive decay chain (Bateman)
- Point reactor kinetics, step reactivity
- Gamma shielding and dose geometry
- Neutron moderation: xi and collisions
All TI-84 Plus CE engineering programs · All TI-84 Plus CE programs