| Variables | Expression | Variables | Expression |
| Dimensionless internal formation pressure |
| Dimensionless outer zone formation pressure |
|
| Dimensionless bottom pressure |
| Dimensionless time |
|
| Dimensionless radius |
| Mobility ratio |
|
| Storage capacity ratio |
| Dimensionless stress sensitivity coefficient |
|
| Dimensionless wellbore survival factor |
|
|
|