MMM106
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| Full Discription | Abbriviation | unit |
|---|---|---|
| dimensionless pressure | pD | psi |
| dimensionless time | pD | psi |
| dimensionless distance | pD | psi |
| dimensionless rate | pD | psi |
| permeability | k | md |
| thickness | h | feet |
| initial reservoir pressure | pi | psi |
| well flowing pressure | pwf | psi |
| initial reservoir pressure | pi | psi |
| production rate | q | STB/d |
| formation volume factor | B | res vol/ std vol |
| viscosity | u | cp |
| Time | t | hours |
| total system compressibility | ct | /psi |
| wellbore radius | rw | ft |
| porosity | Ⴔ | pore volume/bulk volume |
| ... | A | ... |
| ... | S | ... |
Several important parameters in well testing are dimensionless, and they play a crucial role in understanding and analyzing reservoir behavior. Here are a few examples:
The pressure used in well testing is often normalized by the initial reservoir pressure. This dimensionless pressure, often denoted as P/Pi provides a non-dimensional representation of pressure changes in the reservoir.
Time in well testing is often made dimensionless by dividing it by a characteristic time, such as the drainage time or the time at which the well reaches a certain fraction of its ultimate recovery.
Similar to time, distance can be made dimensionless by dividing it by a characteristic length, often the effective drainage radius of the well.
Production rates are often made dimensionless by dividing them by a characteristic flow rate, such as the initial flow rate.