http://www.uni-kl.de/tvt/

Hydro-abrasion study of rotating elements

Jahrestreffen der Fachgruppen Fluidverfahrenstechnik und Wärme- und Stoffübertragung, 20. – 21. März 2013, Baden Baden

Motivation

CFD simulation of slurry erosion

Mehdi Azimian and Hans-Jörg Bart TU Kaiserslautern, Lehrstuhl für Thermische Verfahrenstechnik,

67653 Kaiserslautern, Germany

E-Mail: mehdi.azimian@mv.uni-kl.de

Erosion: Exp. analysis & CFD simulations

Erosion influencing parameters determination

Material loss and surface deformation analysis

Modeling details:

4 erosion models from literature

E = k ∙ f m ∙ w θ ∙ g V ∙ h d ∙ j Hv

f(m): Solid particle concentration w(θ): Flow angle

g(V): Flow velocity h(d): Solid particle size j(Hv): Hardness of target surface

Water-sand; 2 way-coupling

Fig. 1: Slurry tank experimental setup

Conclusions

• Flow properties:

Impact velocity & angle, solid phase

concentration, apparatus geometry

• Solid particles properties:

Size, shape, hardness & density

• Interface:

Target material properties & particle impact

• Liquid-solid flow:

Water & Sand particles

• Specimens material:

Stainless steel 1.4301 Hardness: 235 HV30

• Good agreement of CFD with exp. Results

• Transient simulation results more precise than steady state

• Maximum erosion near edges • Erosion progress towards the

middle of surface

Outlook • Influence of particle breakup

effects on the erosion rate

• Geometry deformation effects on the erosion rate

Acknowledgement: The authors would like to thank ‘‘Stiftung Rheinland-Pfalz für Innovation‘‘ for the financial support.

Fig. 3: Computational grid of the slurry tank

Fig. 4: Erosion progress towards the middle of surface with a) 5%, b) 8%, c) 10% sand concentration

Fig. 10: Comparison of fluid & solid max. velocities Fig. 11: Comparison of fluid & solid avg. velocities

PIV measurements

Fig. 9: PIV measurement fields in the tank

Fig. 5: Material loss of eroded sample versus sand concentration Fig. 6: Material loss of eroded sample versus flow velocity

Fig. 2: Erosion sample holder & the mesh

Fig. 7: Erosion of stainless steel versus sand concentration Fig. 8: Erosion of stainless steel versus rotational velocity

Application of periodic GGI

Momentum transfer: Schiller-Naumann drag force model

Multiple reference of frames (MRF)

Multiple & replaceable mesh files

Steady state & transient simulations