I have a question about differing CO2 injection rates between a single-layer radial model and a multi-layer radial model. I generated a single-layer model with an injection rate of 18 kg/s but when I add additional rock layers above and below the model I can only inject at about 5 kg/s without simulation failure. I'm curious about why this is happening because I had assumed the multi-layer model would have a higher injection rate with more rock layers for leakage and vertical movement of fluid. (The parameters of the layer being injected into do not change between models except for the addition z perm) I'm not particularly savvy with all the mechanics behind this process and am looking for help in understanding the simulation behavior.
Thanks