Description

In this project, we study a Manometer of Venturimeter CFD Simulation by Ansys Fluent, and it has been shown how there is variation in U-tube manometric fluid column. The multiphase  VOF model has been used. A convergent and divergent nozzle has been used to create a pressure difference. One end of the manometer is attached at the throat, and the other at the converging section. There is a rise in the liquid column in the U- tube manometer at the low-pressure region.

Monometer of Venturimeter CFD Simulation by Ansys Fluent

Venturimeters are pressure measurement devices that are commonly used in everyday life. For example, pressures in piping systems are constantly monitored using these devices. The U-tube manometer is a special manometer that gets its name from its U-shaped tube. The straight portions of this U are commonly referred to as the manometer's arms, limbs, or ends. The manometer is typically filled with a dense, colored fluid called the manometer fluid, which is used to visualize the pressure difference between the two ends of the tube. As the pressure at one of its ends increases, the manometer fluid inside the tube is pushed downward at that end.

This causes the manometer fluid to rise at the other end of the device. The difference in the fluid levels between the two ends is then used to measure the pressure difference. When used properly, the manometer, one of the earliest pressure-measuring instruments, is very accurate.   The manometer has no moving parts subject to wear, age, or fatigue. Manometers operate on the Hydrostatic Balance Principle: a liquid column of known height will exert a known pressure when the weight per unit volume of the liquid is known.

Geometry & Mesh

The 2-D geometry of the present model is generated using Design Modeler software.

The meshing of the present model has been done using Ansys Meshing software. The mesh type is unstructured in all of the computational domains, and the element number is equal to 42,413.

CFD Simulation

To simulate the present model, we consider several assumptions:

• The solver is pressure-based.
• The current simulation is unsteady in terms of time.
• The gravity effect is equivalent to -9.81 m.s-1.

Here is a summary of the steps for defining the problem and its solution in the following table:

Monometer Results

First, a volume fraction diagram was drawn in different positions in this simulation. Then two-dimensional contours related to density, streamline, air volume fraction and mercury volume fraction were obtained. The images show that Initially, the height of the liquid column is equal on both sides. But as the gas enters the manometer, the height of the mercury column changes.