All Outputs (22)

Characterising Horizontal Two-Phase Flows Using Structured-Planar Laser-Induced Fluorescence (S-PLIF) Coupled With Simultaneous Two-Phase PIV (S2P-PIV) (2024)
Presentation / Conference Contribution
Sherif, A. A., Hann, D. B., & Johnson, K. (2024, July). Characterising Horizontal Two-Phase Flows Using Structured-Planar Laser-Induced Fluorescence (S-PLIF) Coupled With Simultaneous Two-Phase PIV (S2P-PIV). Presented at 21st International Symposium on Applications of Laser and Imaging Techniques to Fluid Mechanics, Lisbon, Portugal

Understanding the physics that underpins the behaviors of two-phase flows is immensely useful for a diverse number of industries, including oil and gas, nuclear, and aerospace. Stratified air-liquid two-phase flows are amenable to the application of two... Read More about Characterising Horizontal Two-Phase Flows Using Structured-Planar Laser-Induced Fluorescence (S-PLIF) Coupled With Simultaneous Two-Phase PIV (S2P-PIV).

Can simultaneous PIV in the gas and liquid phases provide insight into the transfer of momentum between the two phases? (2022)
Presentation / Conference Contribution
Kim, J. H., Hann, D. B., Eastwick, C. M., & Cherdantsev, A. V. (2022, July). Can simultaneous PIV in the gas and liquid phases provide insight into the transfer of momentum between the two phases?. Paper presented at 20th International Symposium on the Application of Laser and Imaging Techniques to Fluid Mechanics, Lisbon, Portugal

Understanding the interaction between a gas shearing over a liquid film and the liquid film is essential if we wish to use modeling to optimize systems to decrease environmental impact, increase efficiency and hence productivity. To this end, PIV is... Read More about Can simultaneous PIV in the gas and liquid phases provide insight into the transfer of momentum between the two phases?.

Experimental Investigation Into Oil Film Thickness and Behaviour Near an Aero-Engine Bearing (2022)
Presentation / Conference Contribution
Sinha, A., Hann, D., Johnson, K., & Walsh, M. (2022, June). Experimental Investigation Into Oil Film Thickness and Behaviour Near an Aero-Engine Bearing. Presented at ASME Turbo Expo 2022: Turbomachinery Technical Conference and Exposition, Rotterdam, Netherlands

In an aero-engine transmission system, bearings are used for shaft location and load support. These bearings are housed in bearing chambers and oil is supplied to the chamber for lubrication and cooling. To achieve the targets of ACARE Flight-path 20... Read More about Experimental Investigation Into Oil Film Thickness and Behaviour Near an Aero-Engine Bearing.

Studying the impacts of droplets depositing from the gas core onto a gas-sheared liquid film with stereoscopic BBLIF technique. (2022)
Journal Article
Cherdantsev, A. V., Sinha, A., & Hann, D. B. (2024). Studying the impacts of droplets depositing from the gas core onto a gas-sheared liquid film with stereoscopic BBLIF technique. International Journal of Multiphase Flow, 150, Article 104033. https://doi.org/10.1016/j.ijmultiphaseflow.2022.104033

In annular gas-liquid flow, the droplets are torn from the liquid film surface by the turbulent gas stream, accelerate due to the gas drag force and eventually deposit back onto the wavy film surface, hitting it with a high speed at a shallow angle.... Read More about Studying the impacts of droplets depositing from the gas core onto a gas-sheared liquid film with stereoscopic BBLIF technique..

Asymmetrically heated multi-stage travelling-wave thermoacoustic electricity generator (2021)
Journal Article
Kisha, W., Riley, P., McKechnie, J., & Hann, D. (2021). Asymmetrically heated multi-stage travelling-wave thermoacoustic electricity generator. Energy, 235, Article 121312. https://doi.org/10.1016/j.energy.2021.121312

Recent developments of thermoacoustic engines have demonstrated that thermoacoustic technology is a viable option for waste heat recovery and low-cost electricity generation, Thermoacoustic technology is capable of converting low-grade heat to electr... Read More about Asymmetrically heated multi-stage travelling-wave thermoacoustic electricity generator.

Numerical Optimisation of the Regenerator of a Multi-stage Travelling Wave Thermoacoustic Electricity Generator (2021)
Presentation / Conference Contribution
Kisha, W., & Hann, D. (2021). Numerical Optimisation of the Regenerator of a Multi-stage Travelling Wave Thermoacoustic Electricity Generator. In Advances in Heat Transfer and Thermal Engineering: Proceedings of 16th UK Heat Transfer Conference (UKHTC2019) (459-463). https://doi.org/10.1007/978-981-33-4765-6_79

In a travelling wave thermoacoustic engine, the regenerator is the heart of the engine [1], where the thermal interaction between the working gas and the solid material takes place. Unlike the stack in standing wave engine, the regenerator is more of... Read More about Numerical Optimisation of the Regenerator of a Multi-stage Travelling Wave Thermoacoustic Electricity Generator.

Thermoacoustic Electricity Generator for Rural Dwellings in Developing World (2021)
Presentation / Conference Contribution
Kisha, W., & Hann, D. (2021). Thermoacoustic Electricity Generator for Rural Dwellings in Developing World. In Advances in Heat Transfer and Thermal Engineering: Proceedings of 16th UK Heat Transfer Conference (UKHTC2019) (893-897). https://doi.org/10.1007/978-981-33-4765-6_152

Thermoacoustic seems to be a promising technology for waste heat recovery (Blok in J. Acoust. Soc. Am. 123:3541–3541, 2008;Abdoulla-Latiwish et al. in Energy 134:1107–1120, 2017;) and are subject to steadily growing interest, particularly in the fiel... Read More about Thermoacoustic Electricity Generator for Rural Dwellings in Developing World.

The use of POD filtering to study the transition from 2D to 3D in stratified two- phase flow (2018)
Presentation / Conference Contribution
Hann, D. B., Loizou, K., Vasques, J., Tokarev, M. P., & Cherdantsev, A. V. (2018, July). The use of POD filtering to study the transition from 2D to 3D in stratified two- phase flow. Presented at 19th International Symposium on the Application of Laser and Imaging Techniques to Fluid Mechanics, Lisbon, Portugal

The understanding of the velocity profile beneath waves in sheared flow can have implications for the understanding of heat transfer in many applications. In this paper an analysis of the velocity field beneath 2D and 3D waves is performed to underst... Read More about The use of POD filtering to study the transition from 2D to 3D in stratified two- phase flow.

The Influence of Heat Input Ratio on Electrical Power Output of a Dual-Core Travelling-Wave Thermoacoustic Engine (2018)
Presentation / Conference Contribution
Kisha, W., Riley, P. H., Mckechnie, J., & Hann, D. (2018). The Influence of Heat Input Ratio on Electrical Power Output of a Dual-Core Travelling-Wave Thermoacoustic Engine. In HEAT POWERED CYCLES 2018 conference proceedings (67-74)

This paper presents an analytical and experimental investigation of an electricity generator that employs a two-stage looped tube travelling-wave thermoacoustic prime-mover to deliver acoustic power from heat energy, a loudspeaker to extract electric... Read More about The Influence of Heat Input Ratio on Electrical Power Output of a Dual-Core Travelling-Wave Thermoacoustic Engine.

Development of a low-cost, electricity-generating Rankine Cycle, alcohol-fuelled cooking stove for rural communities (2018)
Presentation / Conference Contribution
Kisha, W., Riley, P. H., & Hann, D. (2018). Development of a low-cost, electricity-generating Rankine Cycle, alcohol-fuelled cooking stove for rural communities. In Proceedings of the Heat Powered Cycles Conference 2018 (350-357)

This article describes a novel design and construction of a helical tube flash boiler that uses a 2kW nominal methylated spirit burner to heat an approximately 2.5m long coil of copper pipe fed by a nominal 8 bar electrically operated solenoid water... Read More about Development of a low-cost, electricity-generating Rankine Cycle, alcohol-fuelled cooking stove for rural communities.

Study of bubbles entrapped into a gas-sheared liquid film (2018)
Journal Article
Hann, D. B., Cherdantsev, A. V., & Azzopardi, B. J. (2018). Study of bubbles entrapped into a gas-sheared liquid film. International Journal of Multiphase Flow, 108, 181-201. https://doi.org/10.1016/j.ijmultiphaseflow.2018.07.001

The surface of a thick liquid film under strong gas shear is covered by large-scale disturbance waves and small-scale ripples. Disruption of these ripples on top of disturbance waves by the gas stream leads to the creation of droplets that are entrai... Read More about Study of bubbles entrapped into a gas-sheared liquid film.

Comparison of disturbance wave parameters with flow orientation in vertical annular gas-liquid flows in a small pipe (2018)
Journal Article
Vasques, J., Cherdantsev, A. V., Cherdantsev, M., Isaenkov, S., & Hann, D. B. (in press). Comparison of disturbance wave parameters with flow orientation in vertical annular gas-liquid flows in a small pipe. Experimental Thermal and Fluid Science, 97, https://doi.org/10.1016/j.expthermflusci.2018.03.020

The interfacial wave structure of the liquid film in both upward and downward annular gas-liquid flows in an 11.7 mm pipe were investigated using the Brightness Based Laser Induced Fluorescence technique (BBLIF). Film thickness measurements were carr... Read More about Comparison of disturbance wave parameters with flow orientation in vertical annular gas-liquid flows in a small pipe.

Experimental investigation of oil shedding from an aero-engine ball bearing at moderate speeds (2017)
Presentation / Conference Contribution
Santhosh, R., Hee, J. L., Simmons, K., Johnson, G., Hann, D., & Walsh, M. (2017). Experimental investigation of oil shedding from an aero-engine ball bearing at moderate speeds. In Proceedings of ASME Turbo Expo 2017 : Turbomachinery Technical Conference and Exposition. https://doi.org/10.1115/GT2017-63815

In civil aero-engine transmission system bearings are used for shaft location and load support. An experimental test facility in the University of Nottingham's Gas Turbine Transmissions Research Centre (G2TRC) was designed and commissioned to investi... Read More about Experimental investigation of oil shedding from an aero-engine ball bearing at moderate speeds.

Oil film thickness measurements on surfaces close to an aeroengine ball bearing using optical techniques (2017)
Presentation / Conference Contribution
Hee, J. L., Santhosh, R., Simmons, K., Johnson, G., Hann, D., & Walsh, M. (2017). Oil film thickness measurements on surfaces close to an aeroengine ball bearing using optical techniques. In Proceedings of ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. https://doi.org/10.1115/GT2017-63813

In a civil aero-engine transmission system a number of bearings are used for shaft location and load support. A bespoke experimental test facility in the University of Nottingham's Gas Turbine and Transmissions Research Centre (G2TRC) was created to... Read More about Oil film thickness measurements on surfaces close to an aeroengine ball bearing using optical techniques.

Experimental Investigation Into Crater Morphology for Droplets Impinging on a Moving Film (2017)
Presentation / Conference Contribution
Mitchell, A. J., Hann, D., & Simmons, K. (2017). Experimental Investigation Into Crater Morphology for Droplets Impinging on a Moving Film. In Proceedings of ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. https://doi.org/10.1115/GT2017-63443

Application of high speed filming techniques to the study of rearwards melt ejection in laser drilling (2017)
Journal Article
Jones, C., Hann, D. B., Voisey, K., & Aitken, S. (in press). Application of high speed filming techniques to the study of rearwards melt ejection in laser drilling. Journal of Laser Applications, 29(2), Article 022204. https://doi.org/10.2351/1.4983269

Melt ejection is the dominant material removal mechanism in long, ms, pulse laser drilling of metals, a process with applications such as the drilling of cooling holes in turbine blades. Droplets of molten material are ejected through the entrance ho... Read More about Application of high speed filming techniques to the study of rearwards melt ejection in laser drilling.

Oil film thickness measurements on surfaces close to an aeroengine ball bearing using optical techniques (2017)
Presentation / Conference Contribution
Hee, J. L., Santhosh, R., Simmons, K., Johnson, G., Hann, D., & Walsh, M. (2017, June). Oil film thickness measurements on surfaces close to an aeroengine ball bearing using optical techniques. Presented at ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition, Charlotte North Carolina, USA

In a civil aero-engine transmission system a number of bearings are used for shaft location and load support. A bespoke experimental test facility in the University of Nottingham's Gas Turbine and Transmissions Research Centre (G2TRC) was created to... Read More about Oil film thickness measurements on surfaces close to an aeroengine ball bearing using optical techniques.

Study of the impacts of droplets deposited from the gas core onto a gas-sheared liquid film (2016)
Journal Article
Cherdantsev, A. V., Hann, D. B., Hewakandamby, B. N., & Azzopardi, B. J. (2017). Study of the impacts of droplets deposited from the gas core onto a gas-sheared liquid film. International Journal of Multiphase Flow, 88, 69-86. https://doi.org/10.1016/j.ijmultiphaseflow.2016.09.015

The results of an experimental study on droplet impactions in the flow of a gas-sheared liquid film are presented. In contrast to most similar studies, the impacting droplets were entrained from film surface by the gas stream. The measurements provid... Read More about Study of the impacts of droplets deposited from the gas core onto a gas-sheared liquid film.

A study of droplet impact on static films using the BB-LIF technique (2016)
Journal Article
Hann, D. B., Cherdantsev, A. V., Mitchell, A., McCarthy, I., Hewakandamby, B. N., & Simmons, K. (2016). A study of droplet impact on static films using the BB-LIF technique. Experiments in Fluids, 57(46), https://doi.org/10.1007/s00348-016-2132-x

This paper presents results of single droplet impacts on films of different height taken using the Brightness Based Laser Induced Fluorescence technique (BB-LIF). The dynamics of drop impingement such as the shape of the cavity, residual film thickne... Read More about A study of droplet impact on static films using the BB-LIF technique.

Experimental investigation into droplet impingement upon moving films using high speed video and thermal imaging (2015)
Presentation / Conference Contribution
Mitchell, A. J., Simmons, K., & Hann, D. B. (2015). Experimental investigation into droplet impingement upon moving films using high speed video and thermal imaging. In Volume 1: Advances in Aerospace Technology. https://doi.org/10.1115/IMECE2015-51677

Aeroengine bearing chambers are geometrically complex, typically containing shafts, bearings, seals and stationary components. Oil is supplied for lubrication and cooling and so the chamber contains a highly rotating two-phase (oil/air) flow where th... Read More about Experimental investigation into droplet impingement upon moving films using high speed video and thermal imaging.