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December 7, 2021 at 9:52 am

Erik Kostson

Ansys Employee

So this is wrong: "the cumulative mass fraction in 3rd row should equal to the ratio of the effective mass

**to the total mass**since the upper two rows equal zero!!". What you mention here is closer to the

**ratio of effective mass to total mass**for a mode (so last column in the solve.out table)

Please read through my example above it is

**not the total mass**we divided with it is

**the total effective mass (sum)**which is

**0.130237**in your example in the Y-dir, and it was 67.9 kg in my example (the total mass in that example is somewhere around 75 kg).

So the cumulative mass fraction in you case up to mode 3 is for the 3 modes: 0/0.130237 + 0/0.130237 + 0.992688E-1/0.130237 = 0.762216 which is what we get.

So the value in the solve.out from the solver is of course correct.