PVT Sensitivity to Oil Gravity
Spreadsheet
29 rows x 4 columns
| A | B | C | D | |
|---|---|---|---|---|
| 1 | PVT Sensitivity to Oil Gravity | |||
| 2 | Common Reservoir Conditions | |||
| 3 | Gas Specific Gravity | 0.75 | dimensionless | |
| 4 | Temperature | 200 | degF | |
| 5 | Reservoir Pressure | 3000 | psia | |
| 6 | ||||
| 7 | API Gravity | 25 | 35 | 45 |
| 8 | ||||
| 9 | Calculated Properties | |||
| 10 | Rs at Pres (scf/STB) | 509.6701019 | 720.7574796 | 1019.269803 |
| 11 | Pb (psia) | 2996.701484 | 2996.110041 | 2995.518714 |
| 12 | Bo at Pres (RB/STB) | 1.303551326 | 1.422492461 | 1.603509656 |
| 13 | Dead Oil Visc (cP) | 4.716815518 | 1.311778538 | 0.585369388 |
| 14 | Live Oil Visc (cP) | 1.009442897 | 0.3928499709 | 0.2205936951 |
| 15 | ||||
| 16 | Pressure Sweep at 35 API | |||
| 17 | P (psia) | Rs (scf/STB) | Bo (RB/STB) | μo (cP) |
| 18 | 3000 | 720.7574796 | 1.422492461 | 0.3928499709 |
| 19 | 2500 | 578.7019392 | 1.347299055 | 0.4372895157 |
| 20 | 2000 | 442.3594221 | 1.27718494 | 0.4965201401 |
| 21 | 1500 | 312.8592812 | 1.212745365 | 0.5799631517 |
| 22 | 1000 | 192.0150047 | 1.154850705 | 0.707176885 |
| 23 | 500 | 83.34797494 | 1.105025105 | 0.9245535149 |
| 24 | ||||
| 25 | Summary | |||
| 26 | Pb range | 2995.518714 | to | 2996.701484 |
| 27 | Rs range | 509.6701019 | to | 1019.269803 |
| 28 | Bo range | 1.303551326 | to | 1.603509656 |
| 29 | μo range | 0.2205936951 | to | 1.009442897 |
Description
Compare PVT fluid properties across three oil gravities (25, 35, 45 °API) to quantify how API uncertainty affects bubble point, solution GOR, FVF, and viscosity. Heavy oils (low API) have lower Pb, less dissolved gas, and higher viscosity — light oils are the opposite.
Use case: When lab PVT data is unavailable or uncertain, this sensitivity shows the range of possible fluid behavior for reservoir simulation input.
Workflow
- Inputs: Gas gravity, temperature, reservoir pressure, three API values to compare
- Step 1: At each API, compute Rs at reservoir pressure (Standing)
- Step 2: From Rs, estimate Pb, Bo, dead oil viscosity, and live oil viscosity
- Step 3: Compare key properties side by side
- Output: Property comparison table showing sensitivity to oil gravity
How to use this blueprint
- In Excel, go to the Petroleum Office ribbon tab and click Blueprint Manager
- Search for PVT Sensitivity to Oil Gravity
- Click on the blueprint to preview the spreadsheet template
- Click Insert to place it into your worksheet. Modify the input values to match your data.