Hi, the only way you can do that is to clip your gas rel perm to critical gas saturation...then Mbal will flow oil at RSI until gas saturation exceeds it...

Your kro/g rel perm seems to take sgirr as sgcrit...thus...your gas curve...increases almost from the onset..

Do you have a reliable sgcrit measurement from your scal? if not you should use analogue field data with matched sgcrit...

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