PVT Testing on a Chip
Bubble point and dew point with direct visualization of the phase transition: microfluidic PVT studies of oil and gas condensate at reservoir conditions.
| حجم العيّنة | less than 10 mL |
|---|---|
| Methods | CCE / CME |
| Parameters | bubble point, dew point, phase fraction |
| Fluids | reservoir and volatile oil, gas-condensate and recombined mixtures |
| Mode | stepwise or continuous depressurization, static and flowing |
| Chip | serpentine channel, bypass, extended inlets |
| P–T conditions | per customer program, temperature-controlled circuit and sample |
| Deliverables | report, plots, parameter log, photos and video, EOS data |
PVT data drive reservoir-model parameters, production forecasts and development strategy, and an error in bubble point or dew point carries into reserves calculations. Conventional PVT cells require a large representative sample and long equilibration at every pressure step, and the phase transition is detected indirectly — from volume or pressure changes.
The sample is loaded into a transparent microfluidic chip and studied at controlled temperature, pressure and rate of change, while a camera records the appearance and growth of the second phase in real time. For oil, a CCE test with stepwise depressurization determines bubble point and gas fraction; for gas condensate, a CCE/CME test determines the dew point and captures retrograde condensation.
Beyond the static test, a dynamic mode is available: the phase transition is studied under flow at different rates and pressure gradients, showing how flow affects nucleation, growth and transport of the second phase. The serpentine chip design extends the observed channel length and reduces phase-fraction error.
A test needs less than 10 mL of fluid. Video is synchronized with pressure and temperature logs, and the customer receives not just the critical point but the phase fraction versus pressure for EOS model checking and tuning.