Staggered timesteps with 3 participant coupling

Using preCICE
1

Hello,

I’m trying to implement a 3-participant solver system. The order of execution in one timestep is as follows.

  • Solver C sends data to Solver A.
  • Solver A performs some calculations and sends data to Solver B
  • Solver B performs some calculations and sends data to Solver A
  • Solver A performs some more calculations and sends data to Solver C.

Since each coupling (A->B and A->C) happens only once per timestep, the dt for both couplings should be the same. However, the read/write steps are not concurrent. I was thinking that a staggered coupling scheme, where A couples to C at t, 3t, 5t and so on, while A couples to B at 2t, 4t … would solve my problem.

So my questions are

  1. Is preCICE capable of handling a staggered scheme?
  2. If not, I’m considering having one coupling run at double the frequency, with every other step being a dummy step. What is the most computationally efficient way to run the dummy step? Is it possible to have a timestep without exchanging data?

Thanks for your help!