All Outputs (19)

GT2022-82180 Experimental investigation into oil film thickness and behaviour near an aero-engine bearing (2022)
Conference Proceeding

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 Flightpath 205... Read More about GT2022-82180 Experimental investigation into oil film thickness and behaviour near an aero-engine bearing.

How Do Interfacial Shear and Gravity Affect the Oil Film Characteristics Near an Aero-Engine Bearing? (2022)
Journal Article

Recent demand for reducing carbon emission and for increasing engine efficiency has led aero-engine manufacturers to strive for a better oil flow system. Aero-engine bearing chambers that house the shaft-support bearings are among the most challengin... Read More about How Do Interfacial Shear and Gravity Affect the Oil Film Characteristics Near an Aero-Engine Bearing?.

Can simultaneous PIV in the gas and liquid phases provide insight into the transfer of momentum between the two phases? (2022)
Presentation / Conference

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?.

How do the liquid properties affect the entrapment of bubbles in gas sheared liquid flows? (2021)
Journal Article

A large number of industries use fossil fuels for the purpose of cooling and lubrication utilizing a gas stream that acts as a shearing force on the liquid surface. Decreasing the carbon footprint of these processes needs an improved understanding of... Read More about How do the liquid properties affect the entrapment of bubbles in gas sheared liquid flows?.

Asymmetrically heated multi-stage travelling-wave thermoacoustic electricity generator (2021)
Journal Article

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.

Thermoacoustic Electricity Generator for Rural Dwellings in Developing World (2021)
Conference Proceeding

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.

Numerical Optimisation of the Regenerator of a Multi-stage Travelling Wave Thermoacoustic Electricity Generator (2021)
Conference Proceeding

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.

Development of a low-cost, electricity-generating Rankine Cycle, alcohol-fuelled cooking stove for rural communities (2018)
Conference Proceeding

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.

The Influence of Heat Input Ratio on Electrical Power Output of a Dual-Core Travelling-Wave Thermoacoustic Engine (2018)
Conference Proceeding

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.

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.

Experimental investigation of oil shedding from an aero-engine ball bearing at moderate speeds (2017)
Conference Proceeding

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)
Conference Proceeding

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)
Conference Proceeding

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.

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.

Study of gas-sheared liquid film in horizontal rectangular duct using high-speed LIF technique: Three-dimensional wavy structure and its relation to liquid entrainment (2014)
Journal Article
Cherdantsev, A. V., Hann, D. B., & Azzopardi, B. J. (2014). Study of gas-sheared liquid film in horizontal rectangular duct using high-speed LIF technique: Three-dimensional wavy structure and its relation to liquid entrainment. International Journal of Multiphase Flow, 67, 52-64. https://doi.org/10.1016/j.ijmultiphaseflow.2014.08.003

© 2014 The Authors. The flow of a liquid film sheared by high velocity gas stream in a horizontal rectangular duct was investigated using a high-speed laser-induced fluorescence technique. Measurements of local film thickness were resolved in both lo... Read More about Study of gas-sheared liquid film in horizontal rectangular duct using high-speed LIF technique: Three-dimensional wavy structure and its relation to liquid entrainment.

A power electronic controlled dump load with negligible harmonics for accurate loading used in testing small wind turbines
Presentation / Conference Contribution
Klumpner, C., Al, B., & Hann, D. B. (in press). A power electronic controlled dump load with negligible harmonics for accurate loading used in testing small wind turbines. In 2010 IEEE International Symposium on Industrial Electronics. https://doi.org/10.1109/ISIE.2010.5637240

Permanent magnet synchronous generators (PMSG) are at the core of small scale wind power generators manufactured by a wide range of manufacturers in different configurations: vertical or horizontal axis blades, with various geometries and aerodynamic... Read More about A power electronic controlled dump load with negligible harmonics for accurate loading used in testing small wind turbines.