test_layerx_eng Namespace Reference

Functions
	_result (thrust=lambda k:6800.0 - 2.0 *k, motor=True)
	test_the_file_reads_back_as_the_burn ()
	test_the_header_quotes_the_runs_impulse_and_t0_in_psia ()
	test_the_download_is_named_for_the_motor_inside_it ()
	test_given_dimensions_override_the_run ()
	test_without_dimensions_it_refuses ()
	test_the_header_is_the_drawn_engine ()

Variables
	ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
float	DT = 0.02
int	N = 175

Detailed Description

A Layer X burn exported as a RASP .eng thrust curve for OpenRocket (engine/layerx/eng.py).

Expected values are independent of the exporter:
  * the impulse of a step-held curve is the sum of thrust x step, by hand;
  * the 6.8 kN engine's diameter is its drawn stack, 5.000 in bore + 2 x (0.5 in ablative + 0.25 in
    steel) = 6.5 in = 165.1 mm; its length is the face-to-throat of the chamber plus a Rao 80 % bell,
    recomputed here from A_t, L*, the bore and epsilon.

Function Documentation

_result()

test_layerx_eng._result ( thrust = lambda k: 6800.0 - 2.0 * k, motor = True )

protected

Definition at line 25 of file test_layerx_eng.py.

Referenced by test_given_dimensions_override_the_run(), test_the_download_is_named_for_the_motor_inside_it(), test_the_file_reads_back_as_the_burn(), test_the_header_quotes_the_runs_impulse_and_t0_in_psia(), and test_without_dimensions_it_refuses().

test_given_dimensions_override_the_run()

test_layerx_eng.test_given_dimensions_override_the_run

(

)

Definition at line 92 of file test_layerx_eng.py.

References _result(), and check().

test_the_download_is_named_for_the_motor_inside_it()

test_layerx_eng.test_the_download_is_named_for_the_motor_inside_it

(

)

The file's name and the motor's name in it carry the same mean thrust, the run's (step-held).
The header moved to the run's mean on 2026-11-02 while the download kept the trapezoid's: this
falling curve (6800 N less 20 N a step) read STAR-5070N on the file and STAR-5060N inside it.
By hand: 0.02 s x (175 x 6800 - 20 x 15225) N = 17710 N s over 3.5 s = 5060 N.

Definition at line 75 of file test_layerx_eng.py.

References _result(), and check().

test_the_file_reads_back_as_the_burn()

test_layerx_eng.test_the_file_reads_back_as_the_burn

(

)

Definition at line 39 of file test_layerx_eng.py.

References _result(), and check().

test_the_header_is_the_drawn_engine()

test_layerx_eng.test_the_header_is_the_drawn_engine

(

)

Definition at line 105 of file test_layerx_eng.py.

test_the_header_quotes_the_runs_impulse_and_t0_in_psia()

test_layerx_eng.test_the_header_quotes_the_runs_impulse_and_t0_in_psia

(

)

One impulse, the run's: each sample after Fire carries the step that ends there, so the run
totals a step-held curve (sum of thrust x step, by hand); the header quoted the trapezoid, a third
figure (LE4 (3): 23743.9 against the run's 23737.9 N-s). T-0 in psia at a tenth (ADR 0007): it read
'tanks 544.5709487755134 psia, bottle 3750.0 psig'.

Definition at line 59 of file test_layerx_eng.py.

References _result().

test_without_dimensions_it_refuses()

test_layerx_eng.test_without_dimensions_it_refuses

(

)

Definition at line 99 of file test_layerx_eng.py.

References _result().

Variable Documentation

DT

float test_layerx_eng.DT = 0.02

Definition at line 21 of file test_layerx_eng.py.

N

int test_layerx_eng.N = 175

Definition at line 22 of file test_layerx_eng.py.

ROOT

test_layerx_eng.ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

Definition at line 20 of file test_layerx_eng.py.