Rather than bending moment would it be better to look at column buckling? The non-uniform cross section top to bottom complicates it. Re. ignition, twin plug, the perfect fuel would allow ignition timing at say 1 deg ATDC with max cylinder psig at 10-20 ATDC. No combustion pressure before TDC so no "negative work". Maybe about 40% H2 in air, has about five times the flame speed of gasoline in air I think. Anyone want to try it
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