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
Thermal analysis
Test data analysis
Runtime vs. mixture ratio
Heat flux vs. mixture ratio
Chamber Hg vs. mixture ratio
Embedded TC vs. mixture ratio
Fuel exit temp vs. mixture ratio
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