A python repository for compressible aerodynamics
The goal with this project is to make it easy to determine flow states. This is done by taking compressible aerodynamic tables and computing them. Also more functionality than what is included in the tables is included here as well. This is expected to be a python version of the compressible aerodynamic tables by Virginia tech http://www.dept.aoe.vt.edu/~devenpor/aoe3114/calc.html
Documentation for the project can be found at https://rigel09.github.io/CompAero/
Currently this packet is not available on PYPI. Install can be accomplished locally from the cloned project by running the following command.
python setup.py install
or by running
./install.bat on Windows machines.
This repository allows users to easily simulate the Compressible Aerodynamic Tables found in the back of common text books for Compressible Aerodynamics. By knowing the state for any single value or combination of values the user can easily know the rest of them. The repository also prints out the state of the flow in a human readable format.
Supported Flows
- Isentropic Flows
- Normal Shocks
- Oblique Shocks
- Prandtl Meyer Expansion
- Rayleigh Flow
- Fanno Flow
- Thrust Coefficient
Upcoming Flows
- Conical Shocks
The package also supports a command line tool that launches a UI similiar to the Virginia Tech calculator. After installing the package this can be launched by running
compressible_calculator from the command line. This will launch the UI shown below.
This is still in developement and bugs are still being fixed
Examples.
temp = IsentropicRelations(gamma=1.4, a_a_star=1.0235)
print(temp)Produces
|====================================================================|
| Isentropic Flow State at Mach: 1.1749 |
|====================================================================|
| |
|γ:---------------------------------------------------------------1.4|
|p0/p: 2.3473|
|T0/T:---------------------------------------------------------1.2761|
|ρ0/ρ: 1.8395|
|A/A*:---------------------------------------------------------1.0235|
|====================================================================|
Or:
flow = NormalShockRelations(gamma=1.4, m2=0.5130)
print(flow)Produces
|====================================================================|
| Normal Shock Relations at Mach: 2.4999 |
|====================================================================|
| |
|P2/P1: 7.1243|
|ρ2/ρ1:--------------------------------------------------------3.3332|
|T2/T1: 2.1374|
|P02/P01:------------------------------------------------------0.4991|
|P02/P1: 8.5254|
|Dowstream Mach:------------------------------------------------0.513|
|====================================================================|
The Rayleigh and Fanno Classes can also simulate Heat and Friction
t1 = 300
p1 = 1
po1 = IsentropicRelations.calc_p0_p(3, 1.4) * p1
flow = FannoFlowRelations(1.4, po_po_st=4.23456790)
flow.apply_pipe_parameters(0.4, 11, 0.005)
print()
print(flow)
print()
print("T2: ", t1 * flow.t2_t1)
print("P2: ", p1 * flow.p2_p1)
print("Po2: ", po1 * flow.po2_po1)
flow = RayleighFlowRelations(1.4, mach=1.5)
flow.simulate_heat_addition(1000, 275.2, 287)
print(flow)Produces
|====================================================================|
| Fanno Relations at Mach: 3.0000 |
|====================================================================|
| |
|γ: 1.4|
|T/T*:---------------------------------------------------------0.4286|
|P/P*: 0.2182|
|ρ/ρ*:---------------------------------------------------------0.5092|
|4FL*/D: 0.5222|
|U/U*:----------------------------------------------------------1.964|
|Flow Type: SUPER_SONIC|
| |
|========================= Pipe Parameters ==========================|
|Length For Chocked Flow: 10.4432|
|Is Flow Choked? :-----------------------------------------------True|
|Pipe Length: 11|
|Pipe Diameter:---------------------------------------------------0.4|
|Friction Coefficient: 0.005|
| |
|====================== Down Stream Conditions ======================|
|Mach: 1|
|T/T*:---------------------------------------------------------0.4286|
|P/P*: 1.0|
|P0/P0*:----------------------------------------------------------1.0|
|ρ/ρ*: 1.0|
|4FL*/D:----------------------------------------------------------0.0|
|U/U*: 1.0|
| |
|================= Conditions Across Friction Area ==================|
|p2/p1: 4.5826|
|ρ2/ρ1:---------------------------------------------------------1.964|
|T2/T1: 2.3333|
|P02/P01:------------------------------------------------------0.2362|
|4FL*/D2 / 4FL*/D 1: 0.0|
|U2/U1:--------------------------------------------------------0.5092|
|====================================================================|
T2: 699.9999999081632
P2: 4.582575694187624
Po2: 8.674491157634302
|====================================================================|
| Rayleigh Relations at Mach: 1.5000 |
|====================================================================|
| |
|γ: 1.4|
|T/T*:---------------------------------------------------------0.7525|
|P/P*: 0.5783|
|ρ/ρ*:---------------------------------------------------------0.7685|
|P0/P0*: 1.1215|
|U/U*:---------------------------------------------------------1.3012|
|T0/T0*: 0.9093|
|Flow Type:-----------------------------------------------SUPER_SONIC|
| |
|========================= Pipe Parameters ==========================|
|Heat Req. For Chocked Flow: 27582.0562|
|Is Flow Choked? :----------------------------------------------False|
|Added Heat: 1000|
|Gas Constant R:--------------------------------------------------287|
|Cp: 1004.5|
|T01:-----------------------------------------------------------275.2|
|T02: 276.1955|
| |
|====================== Down Stream Conditions ======================|
|Mach: 1.4869|
|T/T*:---------------------------------------------------------0.7525|
|P/P*: 0.586|
|P0/P0*:-------------------------------------------------------1.1152|
|ρ/ρ*: 0.7718|
|T0/T0*:-------------------------------------------------------0.9093|
|U/U*: 1.2957|
| |
|================= Conditions Across Heat Addition ==================|
|P2/P1: 1.0133|
|ρ2/ρ1:--------------------------------------------------------1.0043|
|T2/T1: 1.009|
|P02/P01:------------------------------------------------------0.9944|
|T02/T01: 1.0036|
|U2/U1:--------------------------------------------------------0.9958|
|====================================================================|
In some cases all the variables may not be necessary. Each of the classes contain static methods for each of the calculations so that a user can use them without creating a class instance. In this case the class acts as a collective namespace for functions that make calculations for the same type of flows.
Example.
NormalShockRelations.calc_po2_po1(1.5, 1.4)
IsentropicRelations.calc_p0_p(1.5, 1.4)Approximately 170 tests are run on the repository to ensure validation of both class constructors and internal functions for calculations. These tests may not catch all scenarios so please open an issue for any more further bugs.
Any contributions must include a test and an example. Any bug fixes need a test that fails and then after the bug is fixed the test must pass.