2007-05-04

Added some plots of predicted vs. measured values for all of the "good" regen runs to date. The predicted values were obtained by using my design spreadsheet but with the actual chamber pressure, thrust, mixture ratio, mDot, etc. from the test data. Note that these runs span quite a period of time:
r = 2.54:   Test 2006-02-25-Run1
r = 1.49:   Test 2007-02-25-Run1
r = 3.48:   Test 2007-04-21-Run2
r = 1.73:   Test 2007-04-22-Run1
r = 2.07:   Test 2007-04-22-Run2

The run at r = 1.49 is somewhat suspect as there were some small steps in thrust and chamber pressure during the run so I think there may have been a partial blockage in one of the fuel or oxidizer orifices.

The main problem I see with these comparisons is that the trend of experimental data is almost exactly backwards from what I would expect. My leading theory at this point is my split triplet injector has such a concentrated core that at the higher LOX flows, much of the combustion is taking place outside the chamber.


Pre-test analysis

composite-3c.png

Thermal analysis



Test data analysis

Regen2_Comparisons_20070502_runtimeVsMdotO.pdf

Runtime vs. mixture ratio

Regen2_Comparisons_20070502_HeatFluxVsMixtureRatio.pdf

Heat flux vs. mixture ratio

Regen2_Comparisons_20070502_HgVsMixtureRatio.pdf

Chamber Hg vs. mixture ratio

Regen2_Comparisons_20070502_EmbeddedTcVsMixtureRatio.pdf

Embedded TC vs. mixture ratio

Regen2_Comparisons_20070502_FuelTempVsMixtureRatio.pdf

Fuel exit temp vs. mixture ratio