# Presentation: 876389

## Adam Preece, Paul Tucker & Yan Liu
Fluid Dynamics Research Centre

- Adam Preece, Paul Tucker & Yan Liu
- Fluid Dynamics Research Centre

**Modelling Synthetic Jets using CFD**

## Problem Definition

**Problem Definition**

- Case 1- Synthetic Jet in quiescent air
- Model a synthetic jet from a *0.05”* slot into a *24”x24”* box
- Frequency=*444.7Hz*
- Amplitude=*30ms**-1*

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Simulations

**Simulations**

- NEAT finite volume code by Tucker [1]
- Run using a SunFire 6800 with 24 950MHz processors & 12GB RAM (typical times of about 3-4 days per run)
- Turbulence models implemented as in Liu [2]

- [1] Tucker, P.G. “Computation of Unsteady Internal Flows” Kluwer Academic Publishers, 2001; Appendix G
- [2] Liu, Y. “Numerical simulations of unsteady complex geometry flows” University of Warwick, 2004

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Implementing the unsteady jet

**Implementing the unsteady jet**

- Jet simulated using unsteady boundary conditions at inlet and outlet

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Grid Meshing

**Grid Meshing**

- Non-uniform rectangular grid with a grid expansion factor of 1.15.
- 100x50 nodes (5k)
- Finer grids investigated & looking promising

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Turbulence Modelling

**Turbulence Modelling**

-     Turbulence models used
- Low Reynolds number *k*-** model [3]
- Cubic *k*-** model [4]
- Explicit Algebraic Stress Model (EASM) [5]

- [3] Launder, B. E. and Sharma, B. I., “Application of the energy-dissipation model of turbulence to the calculation of flow near a spinning disc,'*Letters in Heat and Mass Transfer*, Vol. 1, pp. 131--136, 1974.
- [4] Craft, T. J. and Launder, B.E., “Development and application of a cubic eddy-viscosity model of turbulence,'' *Int. J. of Heat \& Fluid** **Flow*, Vol. 17, pp. 108--115, 1996.
- [5] Gatski, T. B. and Speziale, C. G. “On Explicit Algebraic Stress Models (EASM) for complex turbulent flows,'' {\it J. Fluid Mech.}, Vol. 254, pp. 59--78, 1993.

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Numerical Parameters

**Numerical Parameters**

- Modified Central Differencing method, CONDIF [6] used for spatial discretization
- Crank-Nicolson for temporal discretization
- Frequency set at *444.7Hz*
- Jet amplitude of *30ms**-1* with a 7th power profile
- Timestep set at *1/10**th* of *1**°* (*6.25x10**-7**s*)
- Courant number is unity at most

- [6] Runchal, A. K., “CONDIF: A modified central-difference scheme for convective flows” *Int. J. Numer. Meth. in Engrg*, Vol. 24, pp. 1593-1608, 1987.

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Long Time Average

**Results- Long Time Average**

- PIV Results

- k- Results

_***v***__**-velocity Contour Plots**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Long Time Average

**Results- Long Time Average**

- PIV Results

- Cubic Results

_***v***__**-velocity Contour Plots**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Long Time Average

**Results- Long Time Average**

- PIV Results

- EASM Results

_***v***__**-velocity Contour Plots**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Long Time Average

**Results- Long Time Average**

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Long Time Average

**Results- Long Time Average**

_**Line Plots**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Long Time Average

**Results- Long Time Average**

_**Line Plots**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Long Time Average

**Results- Long Time Average**

_**Line Plots**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Phase Average

**Results- Phase Average**

- PIV Results

_***v***__**-velocity Contour Plots**_

- k- Results

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Phase Average

**Results- Phase Average**

_***v***__**-velocity Contour Plots**_

- Cubic Results

- PIV Results

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Phase Average

**Results- Phase Average**

- PIV Results

_***v***__**-velocity Contour Plots**_

- EASM Results

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Phase Average

**Results- Phase Average**

_**Line Plots (Phase 0**__**0 **__**aligned)**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Phase Average

**Results- Phase Average**

_**Line Plots (Phase 0**__**0 **__**aligned)**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Phase Average

**Results- Phase Average**

_**Line Plots (Phase 0**__**0 **__**aligned)**_

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Time History

**Results- Time History**

- Variation of *u* & *v* over time at 3 points.

*x=0mm, y=0.1mm*

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Time History

**Results- Time History**

- Variation of *u* & *v* over time at 3 points.

*x=0mm, y=2mm*

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Time History

**Results- Time History**

- Variation of *u* & *v* over time at 3 points.

*x=1mm, y=2mm*

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Results- Time History

**Results- Time History**

- Variation of *u* & *v* over time at 3 points.

*x=1mm, y=2mm*

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)

## Further Work

**Further Work**

- Further Grid Investigation
- Cross-flow effects
- Adaptive Time Stepping
- Large Eddy Simulation (LES)
- Curvilinear Grid Implementation

**Notes:**

16700 Students
Includes visiting and exchange students (heads) and HEFP students in local colleges.  Excludes students taught overseas and on external programmes.
3800 Staff 
3000 full and part time, 800 casua, 96% non-academic staff live in Coventry. 3rd largest employer in Coventry area
£174.5 m turnover
For year ended July 2001, projected to rise to £222 m by 2004/05
Arts Centre
250,000 visits each year, 70% of audience from Coventry/Warwickshire, 67% self-generated income.  £580,000 University subsidy to Arts Centre each year (not all grant)