The use of changing-skin factors on gas well-testing interpreting;

A new model of skin factor and productivity ratio evaluation for horizontal wells with various completion systems

Application of skin factor in the deliverability testing of horizontal wells in gas reservoir

In traditional real-time monitoring, wellhead pressure and acid injection volume are used to estimate changes of the skin factor during the acidizing process.

However, produced by non-stabilized well test, the overall skin coefficient is not only affected by damage to near-well bore reservoir by drilling/completion fluid, but also affected by completion degree of wells and other stimulation measures, so it should not be used to e-valuate a procedure of a well's construction work.

The biggest effectiveness is to adjust the hydraulic fracture after goals optimum and decided by skin coefficient,wells position and so on.

When well testing interpretation models applied to sandstone or carbonate reservoirs were solved, the instability of early phase data was caused by negative skin coefficient.