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POISE should halt if rotational frequency is close to pericenter angular frequency

Open RoryBarnes opened this issue 4 years ago • 3 comments

A halt needs to be added to ensure POISE is not used at high eccentricity.

RoryBarnes avatar Apr 23 '21 17:04 RoryBarnes

can you please elaborate

vmk8826 avatar May 01 '21 04:05 vmk8826

Yes, of course! When a planet's instantaneous frequency becomes close to the rotational frequency, i.e. periastron of a high eccentricity orbit, then the assumptions underpinning POISE fail and the code should halt. This feature would be valuable when testing extreme climate variations with POISE coupled to an orbital model and the user was not sure how large the eccentricity could reach (see examples/ChaoticResonances). Whlie there is a dHaltMaxEcc option, the default value is 1.0, but for POISE the default should be something like 0.9. To make this change, one would need to modify halt.c:fniHaltMaxEcc to check if POISE was selected and if true, update dHaltMaxEcc to 0.9.

RoryBarnes avatar May 01 '21 20:05 RoryBarnes

Actually, it'd probably be better to modify VerifyHalts in halt.c such that if POISE is selected, then dHaltMaxEcc is set to 0.9. Then there will be no need to perform an extra check in fniHaltMaxEcc, which would increase performance since that function is called every timestep.

RoryBarnes avatar May 03 '21 18:05 RoryBarnes