Fluid Dynamics:

Fluid Dynamics

  • Char conversion for oxyfuel in CFD calculations

    Radiative transfer for particles in high temperature environments

    Supervisor: Professor Mohamed Pourkashanian, Professor Lin Ma, Professor Derek B Ingham and Dr Alastair G Clements

    Heat transfer to solid-phase particles is an important phenomenon for many flows of practical interest.  Modelling will play a key role in the design of optimisation of these systems, however there is a need to adapt currently adopted models for calculating the heat transfer to the solid phase particles.  Some of the challenges to the current approach is accounting for the irregular shapes of some particles, which can depart significantly from the ideally spherical assumption that is widely adopted, and accounting for the strong variations in scattering angles.  Studies into investigating the impact of these shape irregularities and scattering directions on the radiative transfer to the particle and within the fluid domain, the dominant mode of heat transfer at high temperatures, are required to better represent these processes.

     

     

     

  • Char conversion for oxyfuel in CFD calculations

    Novel cathode electrodes for PEM fuel cells

    Supervisor: Professor Mohamed Pourkashanian, Professor Lin Ma, Dr Kevin Hughes and Dr Mohammed S Ismail

    Proton exchange membrane (PEM) fuel cells can operate at low temperatures and are scalable. Therefore, they can be used in a wide range of applications, such as portable, automotive and stationary applications. The cathode electrode is the main source of performance loss in PEM fuel cells. This is due to low utilisation of the catalyst and the slow reaction rate. The main objective of this project is to optimise the structure of the cathode electrode to substantially increase its utilisation. Modelling tools will be used to optimise the structures of the catalyst before synthesising and testing them.

    For further information please contact Professor Derek B Ingham on d.ingham@sheffield.ac.uk.

  • Char conversion for oxyfuel in CFD calculations

    Inflow generation for Large Eddy Simulation (LES) of the wind farms

    Supervisor: Supervisor: Professor Lin Ma, Professor Mohamed Pourkashanian, Professor Derek B Ingham and Dr Ava Shahrokhi

     

    Wind farms are large regions usually outside cities and include a number of wind turbines. An accurate simulation of the flow in the wind farm is essential in the design of the wind farm. This project concerns the turbulent inflow generation for large eddy simulation of the wind flow at wind farms.  Inflow generation techniques are among the top notch research topics in the wind engineering field. This instantaneous value of the velocity components consists of their mean and fluctuating values. This information is not known a priori, so it has to be evaluated in an accurate way. Currently, there are two main techniques for this purpose, the recycling (precursor) methods and synthetic methods. The first method is computationally very time consuming while the second method is not accurate for turbulent wind simulations. Therefore, this project will concern an alternative solution for inflow generation which can replace either of these techniques.

    This project, requires a good understanding of CFD and during the work includes simulations using ANSYS/FLUENT.  

    .

  • Char conversion for oxyfuel in CFD calculations

    Large Eddy Simulation Around Buildings (LES)

    Supervisor: Supervisor: Professor Lin Ma, Professor Mohamed Pourkashanian, Professor Derek B Ingham and Dr Ava Shahrokhi

     

    Computational Wind Engineering has been developing rapidly over the last couple of decades. Among the numerical techniques, Large Eddy Simulation (LES) is capable of simulating complex unsteady turbulent flows, which is very useful for applications such as wind-induced noise/vibrations around buildings and structures. LES is among the top-notch and the most challenging CFD techniques. This project has three major parts.

    1)  Large eddy simulation using different subgrid-scale models.

    2) Boundary condition studies: The correct top and bottom boundary condition that help to maintain the turbulence properties in the domain and also the use of the correct turbulence inlet properties and implementation.

    3) Inflow generation: In order to implement LES around building, it is very important to simulate the wind effects correctly. This requires that the fluctuations of the flow to be initialized properly so that they can represent the wind in the computational domain. The main contribution of this project will be this last part which is also a very challenging part.