PhD project: differentially heated cavity experiments
In my PhD project I developed methodology for measuring three-dimensional flow fields and two-dimensional surface temperatures of turbulent natural convection in a high-vertical-aspect-ratio Differentially Heated Cavity (DHC) for numerical accuracy assessment. I independently took the project from concept and requirements definition through CFD-informed thermal design, detailed mechanical design, manufacture and systems integration to commissioning, experimental operation and data analysis. The project comprised three stages:
- Designing and building a pilot rig to demonstrate the feasibility of optical particle-based measurements in wall-bounded turbulent natural convection and inform the main-rig design.
- Designing and building the main rig system to acquire volumetric DHC flow-field data and wall-temperature measurements suitable for defining computational thermal boundary conditions.
- Performing corresponding direct numerical simulations (DNS) using Nektar++ and comparing them with the experimental data to assess the developed methodology.
The following sections summarise the first two stages.
- Year
- 2021–2025
- Organisation
- CDT in Fluid Dynamics, University of Leeds
- Role
- PhD researcher · Lead experimental designer
- Focus
- Experimental fluid dynamics, Test systems, Instrumentation
- Attachment
Pilot rig
Preliminary test rig was designed and built to inform the design and build of the final test rig. The rig was designed to accommodate 2D-PIV and 3D-PTV data acquisition of turbulent natural convection flow field, observe three-dimensional flow, and identify challenges and potential issues for the final rig.
- Created a detailed rig CAD using Solidworks, selected materials, and components prioritising straightforward manufacture, assembly and modification.
- Designed heater electrics and control circuitry along with simple DAQ for temperature measurements using thermocouples.
- Built the mechanical rig, electrical control and DAQ systems, integrating them into a coherent, fully operational experimental platform.
- Succesfully carried out experiments with both 2D-PIV and 3D-PTV systems, analysed results and contributed to the current knowledge of vertical wall-bounded turbulent natural convection.
Main rig
Main rig was designed to accomodate two geometrically identical tanks. The visual tank was developed for the first-ever time-resolved 4D PTV measurements of turbulent natural convection in a differentially heated cavity. The thermal tank replicated the visual tank geometry but also incorporated arrays of thermocouples at DHC walls, as well as a dedicated DAQ system for measuring two-dimensional wall-temperature distributions.
- Ansys Fluent CFD informed sizing of the working volume, heating and cooling jackets and set the requirements for thermal conditioning system.
- Created a detailed SolidWorks CAD model of the complete rig, designed it for manufacture and assembly, and produced technical drawings with GD&T for manufacture.
- Sized and sourced heater, chiller, heat exchangers, and pumps. Designed and built plumbing system.
- Selected and integrated the thermocouples, and built a dedicated DAQ system.
- Succesfully carried out experiments with both visual and thermal tanks, analysed results and contributed to the current knowledge of turbulent natural convection in a high-vertical-aspect-ratio DHCs.