Transient simulation of flow through throttle body
Project objective :
To perform a transient simulation of flow over a throttle body and to study the behavior of fluid and its various properties.
Geometry :
Software tools used :
- Simulation - Converge CFD studio (v2.3)
- Command editor - Cygwin
- Post-processing - Paraview
Case setup :
- General flow gas simulation
- Solver type: Transient
- Inflow pressure: 150000.0 Pa
- Outflow pressure: 100000.0 Pa
- Species: Air (O2-23%,N2-77%)
- Turbulence model: RNG k-ε
- Fixed embedding around throttle valve - Scale: 3, no.of layer: 2
- Wall temperature: 300k
- Grid size: 2 mm
Simulation outputs:
The movement of the throttle valve has been given below :
- 0 to 2 ms - stays at 0 degree
- 2 to 4 ms - moves to 25 degree
- 4 to 8 ms - moves to 0 degree
- After 8 ms - stays at 0 degree
With Converge, the mesh generation process is 100% automatic. A base mesh of 2mm has been used. Fixed embedding has been enabled around the throttle valve to capture data even more accurately as the clearance between the throttle valve and the body is very small.
The above video shows the velocity streamlines and the valve is color contoured with pressure. The velocity maximizes up to 310 m/s.
The above image shows the velocity streamlines when the valve is at 25 degrees (4 ms).
Mass flow rate vs time:
Total cells vs time:
From the above plots it can be observed that whenever the throttle valve moves, the values change rapidly. In the case of total cell vs time plot, it can be noted that the cell count maintains a particular value from 2 to 4ms and from 8 to 10ms meaning that the valve is stationary within those period of time.