List of top Petroleum Engineering Questions on Fluids

The mean free path of the gas molecule is $10^{-6}$ mm, while the pore size of the rock is $10^{-3}$ mm. Which of the following statements is TRUE?

Surface tension of liquid A in a capillary is being measured in the laboratory using capillary rise (refer the figure given below). The capillary radius \( r \) is 100 \(\mu\)m, the height of liquid column \( h \) is 10 cm and \( \Theta = 38^\circ \). Density of air can be neglected. Assume liquid A to have the same density as water. Surface tension of liquid A at room temperature is \(\underline{\hspace{2cm}}\) dyne/cm (round off to one decimal place). 

A porous medium (shown schematically in the figure) has the following properties. 
\(\text{Length } L = 600 \, \text{m}, \text{ Width } W = 8 \, \text{m}, \text{ Height } h = 0.5 \, \text{m}, \text{ Permeability } k = 100 \, \text{mD}, \text{ Porosity } \phi = 15%.} \)

An incompressible fluid having a viscosity of 2 cP is flowing through a porous medium at the inlet and exit pressures of \(7 \times 10^6 \, \text{Pa and } 6 \times 10^6 \, \text{Pa, respectively.} \) The actual fluid velocity through the porous medium is \(\underline{\hspace{2cm}} \times 10^{-7} \, \text{m/s.}\)

When CO\(_2\) and liquid water are brought in contact with each other, they may form solid hydrates. The three-phase hydrate boundary is shown in the Pressure-Temperature plot given below. Identify the correct statements. 

Pressure – Temperature phase diagram of CO\(_2\) is shown below. Identify the correct phases from the given options. 
 

In the original Darcy's law as proposed by Henry Darcy, which of the following drives the fluid flow through a fully saturated sand column?
At which ONE of the following scales is Darcy's law for fluid flow through a porous medium applicable?
Miscible displacement process is one of the EOR techniques. The performance of this process depends on fluid physical properties that affect flow behavior in a reservoir. Two of the important properties are density and viscosity. Consider the use of CO\(_2\) for one such process. The density of CO\(_2\) at the reservoir condition is \(\underline{\hspace{2cm}}\) lb/ft\(^3\) (round off to one decimal place). Relevant data for this calculation are given below.
- Reservoir temperature = 300 ºF (422 K)
- Reservoir pressure = 1470 psig (100 atm)
- Compressibility factor (\(z\)) at the reservoir condition = 0.5
- Values of Universal Gas Constant (\(R\)) in different units are listed below:
- \( R = 8.314 \, \text{m}^3 \, \text{Pa.K}^{-1} \, \text{mol}^{-1} \)
- \( R = 10.731 \, \text{psi.ft}^3 \, \text{lb.mol}^{-1} \, \text{ºR}^{-1} \)
- \( R = 0.082 \, \text{L} \, \text{atm.K}^{-1} \, \text{mol}^{-1} \)
When two immiscible fluid phases are placed in contact with a solid surface, one phase usually is attracted to solid more strongly than the other phase. The more strongly attracted phase is called the 'wetting phase'. The inter-molecular interaction of the non-wetting phase with the solid is \(\underline{\hspace{2cm}}\)I\(\underline{\hspace{2cm}}\) than its intra-molecular interaction. Due to this, the non-wetting phase tends to occupy the \(\underline{\hspace{2cm}}\)II\(\underline{\hspace{2cm}}\) of the reservoir.