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Abstract Based on the characteristics of acid fracturing and the relationship of solid deformation and liquid flow，a comprehensive model for production testing is proposed，which includes intact region，etched region and propped fracture. The effects of effective stress on fluid parameters are different in different zones. Based on elasticity mechanics，for intact and etched regions，a model for change of porosity is established，and fracture conductivity tests are conducted to obtain a model of permeability change with effective normal stress. It is found that，for specific proppants，the change pattern of permeability of propped fracture changes when the closure stress exceeds compressive strength of etched rock which shows a permanent damage by proppant embedment. Considering the difference of three zones，a solid-liquid coupling algorithm is presented to calculate the distribution of effective stress. The measured data agree well with model results by field application.
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Received: 24 July 2008
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