Multi-Phase Flow in an Injector CFD Simulation

Injector Project Description

The present problem is going to simulate an injector. The Multi-Phase model, which consists of air and water flows is used. Water flows through three curved ducts into a reservoir that only has airflow inside its space. The curved structure of the ducts and the cone-shaped state on the air-filled tank distributes the water flow vortices into the injector, thereby discharging the water out of the surroundings of the cylindrical chamber (near the chamber wall) of the injector.

Assumption

There are several assumptions used for the present simulation:

The solver is Pressure-Based, the simulation is Steady, and the effect of Earth’s gravity on the model equals 9.81 m.s-2.

Geometry and Mesh

The 3-D geometry of the present model is designed by Design Modeler software. There are three ducts with a square cross-section for water flow, a conical-shaped area, and a cylindrical chamber. The meshing of the present model is performed by ANSYS Meshing software. The mesh type was unstructured and the element number was 102752.

Injector CFD Simulation (Multi-Phase)

Summaries of the problem definition and problem-solving steps are summarized in the table:

Models
k-epsilon	Viscous model
standard	k-epsilon model
standard wall functions	near-wall treatment
VOF		Multiphase model
water, air	phases
sharp	interface modeling
implicit	volume fraction formulation
Boundry conditions (injector)
mass flow inlet	Inlet type
0.01 kg.s-1	water – mass flow rate
0 kg.s-1	air – mass flow rate
Pressure outlet	Outlet type
0	water – backflow volume fraction
1	air – backflow volume fraction
wall		Walls type
Solution Methods (injector)
Coupled		Pressure-velocity coupling
PRESTO	pressure	Spatial discretization
second order upwind	momentum
first order upwind	turulent kinetic energy
first order upwind	turulent dissipation rate
compressive	volume fraction
Initialization (injector)
Standard	Initialization method
-13.341 m.s-1	z-velocity
0	water volume fraction

There is a mesh file in this product. By the way, the Training File presents how to solve the problem and extract all desired results.