E-CodeIsentropic flow and normal shock — a TI-84 Plus CE program
ISENT is a TI-BASIC program for the TI-84 Plus CE. Perfect-gas tables on demand: Mach to T, p, rho and A/A*; area ratio back to Mach (subsonic or supersonic branch); and every normal-shock ratio.
What it asks for and what it shows
It asks for 2 values at its prompts, after you pick option 1 from its menu. In the example below it shows T/T0, P/P0, RH/RH0, A/A*.
Example run
One of its oracle test cases: “ratios: air, Mach 2”. 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 | 1.4 |
| Input 2 | 2 |
| The screen shows | |
T/T0= | 0.5555555556 |
P/P0= | 0.1278045255 |
RH/RH0= | 0.2300481458 |
A/A*= | 1.6875 |
How it's checked
13 test cases, each checked against an independent method. Replayed key by key on a virtual TI-84 Plus CE, they make 78 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 “Isentropic flow and normal shock” (ISENT).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
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All TI-84 Plus CE engineering programs · All TI-84 Plus CE programs