Anubhav Baranwal When modeling local scour around a bridge pier in ANSYS FLUENT, there are a few steps you can take to pick bed material as well as flow:

1. Select "Material Parameters" from the "Define" menu to define the bed material's properties. In this option, you may set the density, viscosity, and specific heat of the bed material.

2. Select "Discrete Phase Model" from the "Specify" option to define the bed material's attributes as discrete phase. This menu allows you to customize the size, quantity, and attributes of the particles.

3. Select "Boundary Conditions" from the "Set" menu to define the flow conditions at the domain's inlet and exit. You can control the velocity, pressure, and turbulence.

4. To begin the simulation, pick "Initialize" from the "Solve" menu. Based on the supplied boundary conditions, this will set the beginning conditions for the simulation.

5. To begin the simulation, pick "Run" from the "Solve" menu. In the post-processing step, you may monitor the simulation's progress and examine the results.

6. To display the simulation results, pick "Plot Results" from the "Post-Processing" option. You can see the velocity, pressure, and turbulence fields, as well as the particle movement in the bed material.

It is important to note that scouring around bridge piers is a complicated phenomena that is affected by a variety of parameters, including the shape of the bridge pier, the flow rate, and the qualities of the bed material.

Some resources that may be useful in addressing this issue include:

- The ANSYS FLUENT User's Guide contains in-depth information on the program and how to use it to model scour around bridge piers.

- J.C. Frost and F.J. Weber's "River Engineering and Sediment Transport". This book describes in depth the processes involved in scouring around bridge piers and how to simulate them.

- The Federal Highway Administration's (FHWA) "Scour at Bridges" guidance offers the information required to analyze scour at bridge locations and proposes solutions to lessen or avoid scour.

- NCHRP Report 641, "Scour at Bridge Foundations," provides information and guidelines on the prediction and mitigation of scour at bridge foundations.

Thank you so much