MATHEMATICAL MODELING OF PRESSURE AND ION DIFFUSION BEHAVIOR ON REACTIVE SHALE

Oil based muds (OBMs) were applied during drilling in reactive shales for a long time. But high costs and environmental concerns changed drilling orientations and water based muds (WBMs)were used again with new approach. In present paper, some new strategies which should be consideredin order to prevent troublesome instabilities in shale were modelled and calculated and the results were examined with laboratorial measured data. Outcomes of the models disclosed some new schemes in drilling and confirmed some other previously proved practical results in shale drilling.

Keywords:

pressure and ion diffusion , hydraulic diffusivity , membrane efficiency , phenomenological coefficients , mathematical modeling