Harvey Morpeth Thompson

• BA in Mathematics, University of Cambridge, Pembroke College; PhD in Mechanical Engineering, School of Mechanical Engineering, University of Leeds
• Professor (Full) at University of Leeds

Few previous experimental studies have focused on pre-mixed turbulent burning velocities (ut) for hydrogen/air and methane/hydrogen/air mixtures, especially at the high-pressure conditions most relevant to gas turbine applications. This work employed a Schlieren technique to measure flame speeds for such mixtures in a spherical stainless steel comb...

Citation: Mahmood, A.; Cockerill, T.; de Boer, G.; Voss, J.; Thompson, H. Heat Transfer Modeling and Optimal Thermal Management of Electric Vehicle Battery Systems. Energies 2024, 17, 4575. https://doi.org/10.3390/en17184575. Abstract: Lithium ion (Li-ion) battery packs have become the most popular option for powering electric vehicles (EVs). Howev...

Spherically expanding flame propagations have been employed to measure flame speeds for H2/CH4/air mixtures over a wide range of H2 fractions (30 %, 50 %, 70 and 100 % hydrogen by volume), at initial temperatures of 303 K and 360 K, and pressures of 0.1, 0.5 and 1.0 MPa. The equivalence ratio (ϕ) was varied from 0.5 to 2.5 for pure hydrogen and fro...

The development of Polymerase Chain Reaction Mullis et al. in 1986 [1] (PCR) has played an important role in the progress of molecular diagnostics, enabling the rapid DNA amplification through a series of repeated cycles. Considering the wide use of PCR devices in research, there is a great need to optimize their performance. This study focuses on...

Polymerase Chain Reaction (PCR) is widely used in biological research labs in order to detect hereditary diseases, diagnose infectious diseases, clone genes and other purposes. This work focuses on combining CFD and response surface modelling to explore the dependence of DNA amplification on two design parameters in a single phase, continuous flow...

A novel Computational Fluid Dynamics-enabled multi-objective optimisation methodology for Polymerase Chain Reaction flow systems is proposed and used to explore the effect of geometry, material and flow variables on the temperature uniformity, pressure drop and heating power requirements, in a prototype three-zone thermal flow system. A conjugate h...

jats:p>The invention and development of Polymerase Chain Reaction (PCR) technology have revolutionised molecular biology and molecular diagnostics. There is an urgent need to optimise the performance of these devices while reducing the total construction and operation costs. This study proposes a CFD-enabled optimisation methodology for continuous...

The internal dynamics during the axisymmetric coalescence of an initially static free droplet and a sessile droplet of the same fluid are studied using both laboratory experiments and numerical simulations. A high-speed camera captured internal flows from the side, visualised by adding a dye to the free droplet. The numerical simulations employ the...

The internal dynamics during the coalescence of a sessile droplet and a subsequently deposited impacting droplet, with either identical or distinct surface tension, is studied experimentally in the regime where surface tension is dominant. Two color high-speed cameras are used to capture the rapid internal flows and associated mixing from both side...

The first CFD-enabled multi-objective design optimisation methodology for continuous oscillatory baffled reactors (COBRs), used for flow chemistry-based process development, is described, where performance is quantified in terms of two metrics: a mixing efficiency index and the variance of the residence time distribution. The effect of cross-valida...

The flow distribution and central processing unit (CPU) temperatures inside a rack of thirty 1U (single rack unit) Sun Fire V20z servers retrofitted with direct to chip liquid cooling and two coolant pumping configuration scenarios (central and distributed) are investigated using the EPANET open source network flow software. The results revealed th...

The evaporation characteristics of sessile droplets on heated hydrophobic and hydrophilic surfaces are investigated. Results are reported for the evaporation of water droplet volumes covering a range of shapes dominated by surface tension or gravity and over a range of temperatures between 40℃ and 60℃. The weight evolution and total time of evapora...

The convective heat transfer, pressure drop and required pumping power for the turbulent flow of Al2O3-water, TiO2-water and CuO-water nanofluids in a heated, horizontal tube with a constant heat flux are investigated experimentally. Results show that presenting nanofluid performance by the popular approach of plotting Nusselt number versus Reynold...

Electrohydrodynamic (EHD) air blowers are uniquely positioned to overcome the limitations of miniaturized mechanical fans in small-scale and consumer electronic devices. A novel cooling system design using optimized EHD blowers integrated with a plate-fin heat sink is presented and proposed for thin consumer electronics such as laptop applications....

Electrohydrodynamic (EHD) air blowers are receiving increasing attention as a thermal management cooling solution to overcome the restrictions of traditional rotary cooling systems used in small-scale consumer electronics. In this work, the performance and flow pattern characteristics of miniature EHD air blowers are evaluated for practical convect...

An experimental and numerical investigation of water-cooled serpentine rectangular minichannel heat sinks (MCHS) has been performed to assess their suitability for the thermal management of gallium nitride (GaN) high-electron-mobility transistors (HEMTs) devices. A Finite Element-based conjugate heat transfer model is developed, validated experimen...

Electrohydrodynamic (EHD) air blowers are uniquely positioned to overcome the limitations of miniaturized mechanical fans in small-scale and consumer electronic devices. A novel cooling system design using optimized EHD blowers integrated with a plate-fin heat sink is presented and proposed for thin consumer electronics such as laptop applications....

As the demand for advanced microelectronic devices of small form factor and high power density has increased, the capability of the miniaturized mechanical solutions for effective cooling has become critical. Electrohydrodynamic (EHD) air blowers have great potential as alternative cooling solutions over the traditional mechanical systems to meet t...

The IT infrastructure power consumption constitutes a surprisingly large portion of global electricity consumption. In particular, a large proportion of this energy is consumed by the heat removal systems required to maintain an acceptable thermal environment for the operation of the IT equipment. The effectiveness and efficiency of a large array o...

Electrohydrodynamic (EHD) airflows provide a means of generating air motion by a gas discharge across two electrodes without the need for moving parts. A two-dimensional numerical model for a wire-to-grid EHD air blower is developed, validated against previous data, and used to investigate the influence of key design parameters on blower efficiency...

Datacenter energy consumption constitutes a large portion of global energy consumption. Particularly, a large amount of this energy is consumed by the datacenter cooling system. Subsequently, many innovative cooling technologies have been developed to reduce energy consumption and increase cooling performance. In this work, an experimental setup wa...

This paper investigates the optimization of the aerodynamic design of a police car, BMW 5-series which is popular police force across the UK. A Bezier curve fitting approach is proposed as a tool to improve the existing design of the warning light cluster in order to reduce drag. A formal optimization technique based on Computational Fluid Dynamics...

This paper presents a combined experimental and numerical investigation of single-phase water flow and heat transfer in serpentine rectangular microchannels embedded in a heated copper block. The performance of four different microchannel heat sink (MCHS) configurations are investigated experimentally, the first having an array of straight rectangu...

A multiscale method for the Elastohydrodynamic Lubrication (EHL) of line contacts is derived based on the Heterogeneous Multiscale Methods. Periodicity applies to the topographical features and lubricant flow, data is homogenised over a range of variables at a micro-scale and coupled into a macro-scale model. This is achieved using flow factors as...

Cloud datacenters are compute facilities formed by hundreds and thousands of heterogeneous servers requiring significant power requirements to operate effectively. Servers are composed by multiple interacting sub-systems including applications, microelectronic processors, and cooling which reflect their respective power profiles via different param...

Digital infrastructure is becoming more distributed and requiring more power for operation. At the same time, many countries are working to de-carbonise their energy, which will require electrical generation of heat for populated areas. What if this heat generation was combined with digital processing?

The natural convection cooling system of a fully immersed server in a dielectric liquid is analysed numerically, where the servers are in sealed capsules and submerged in in a dielectric fluid. A reduced order flow model is developed under a saturated porous media flow assumption using a Darcy flow regime and the Stokes equations solved numerically...

The frictional performance of a bearing is of significant interest in any mechanical system where there are lubricated surfaces under load and in relative motion. Surface topography plays a major role in determining the coefficient of friction for the bearing because the size of the fluid film and topography are of a comparable order. The problem o...

The importance of accounting for the temperature dependence of air properties in numerical simulations of air flows over pinned heat sinks is demonstrated by comparisons with recently published experiments. Numerical simulations, based on a conjugate heat transfer analysis, using the RANS-based modified k-ω turbulence model, with temperature-depend...

This paper reviews the key research activities and results produced during the AMEDEO (Aerospace Multidisciplinarity-Enabling Design Optimisation) Marie Curie Initial Training Network (ITN). AMEDEO brought together optimisation researchers and practitioners from European universities, research organisations, multinationals and SMEs to develop innov...

This paper summarises the two part work carried out during project 7 of work package 3 of the EU funded research project AMEDEO. At first, the outcome of a practical application and extension of a numerical coupled FEA-CFD methodology is presented. Extensive use is made of FEA (solids) and CFD (fluid) modelling techniques to understand the thermo-m...

In the most evolved designs, it is common practice to expose engine components to main annulus air temperatures exceeding the thermal material limit in order to increase the overall performance and to minimise the engine specific fuel consumption (SFC). To prevent overheating of the materials and thus the reduction of the component life, an internal...

In the most evolved designs, it is common practice to expose engine components to main annulus air temperatures exceeding the thermal material limit in order to increase the overall performance and to minimise the engine specific fuel consumption (SFC). To prevent overheating of the materials and thus the reduction of the component life, an interna...

This paper illustrates three different methods which can be used to quantify passive ventilation inside small livestock trailers. Accomplishing this is crucial to determine whether animal welfare ventilation standards are met during road transport. High-fidelity Computational Fluid Dynamics (CFD) simulations are conducted for a detailed livestock t...

Rising energy costs and changing legislation are bringing the need for more efficient baking processes into much sharper focus. This will require greater scientific understanding of how to manipulate oven design and baking conditions to produce energy efficient designs. This article highlights the work carried out at the University of Leeds, UK, on...

The benefits of using strip fin heat sinks (SFHSs) where the cross-sectional aspect ratio of the fins lie between those for plate fins (high aspect ratio) and pins fins (aspect ratio≈1) are explored computationally, using a conjugate heat transfer model. Results show that strip fins provide another effective means of enhancing heat transfer, especi...

Nowadays, it is common practice to expose engine components to main annulus air temperatures exceeding the thermal material limit in order to increase the overall engine performance and to minimise the engine specific fuel consumption. To prevent overheating of the materials and thus the reduction of component life, an internal flow system is requi...

A combination of laboratory experiments and a system model are used to carry out the first investigation into the potential for cold air to bypass IT equipment within data centres (DCs) employing aisle containment, and the effect of this bypass on DC electricity consumption. The laboratory experiments involved applying a differential pressure acros...

The benefits of using pinned heat sinks (PHSs) with multiple circular, square and elliptic perforations for electronic cooling applications are investigated using Computational Fluid Dynamics (CFD). A conjugate heat transfer analysis, using the RANS-based modified k-ω turbulence model, is used to determine the effect of perforation shape on the coo...

The benefits of using pin heat sinks (PHSs) with single, rectangular slotted or notched pin perforations, are explored computationally, using a conjugate heat transfer model. Results show that the heat transfer increases monotonically while the pressure drop decreases monotonically as the size of the rectangular perforation increases. Performance c...

This paper presents the first experimental and computational investigation into the aerodynamics of emergency response vehicles and focuses on reducing the additional drag that results from the customary practice of adding light-bars onto the vehicles’ roofs. A series of wind tunnel experiments demonstrate the significant increase in drag that resu...

An efficient Bubnov-Galerkin finite element formulation is employed to solve the Navier-Stokes and continuity equations in three-dimensions for the case of surface-tension dominated film flow over substrate topography, with the free-surface location obtained using the method of spines. The computational challenges encountered are overcome by employ...

A numerical investigation is performed into the effects of the root mean square (RMS) turbulence velocity on the spray characteristics of liquid fuel injected into a constant volume vessel and comparison drawn with experimental data obtained for the case of iso-octane fuel injected into nitrogen showing good agreement between the two. A detailed pa...

In response to increasing energy costs and legislative requirements energy efficient high-speed air impingement jet baking systems are now being developed. In this paper, a multi-objective optimisation framework for oven designs is presented which uses experimentally verified heat transfer correlations and high fidelity Computational Fluid Dynamics...

Derived from the Heterogeneous Multiscale Methods (HMM), a two-scale method is developed for the analysis of Elastohydrodynamic Lubrication (EHL) and micro-EHL in tilted-pad bearings with three-dimensional topography. A relationship linking the pressure gradient to mass flow rate is derived and represented in the bearing domain through homogenisati...

The growth in demand for Information Technology (IT) systems and the requirements to better control carbon emissions is a large challenge for data centre design. Air-cooled data centres are becoming more efficient by layout and the adoption of compressor free cooling, but for higher densities, further efficiencies can be achieved with liquid (water...

Data centers are large consumers of power, of which a large proportion is spent on removing the heat generated by the semiconductors inside IT servers. This paper develops a full analysis of the cooling system when servers are immersed in a dielectric liquid and water is used to transport the heat outside of the data center. The analysis combines e...

Coolant technologies have become increasingly used within twist-drill machining. Internal helical coolant channels are a common means of delivering high-pressure coolant directly to the cutting edge to increase the transfer of heat away from the cutting edge and to aid with chip evacuation. However, the complex behaviour of Coriolis and centrifugal...

Numerical noise is an unavoidable by-product of Computational Fluid Dynamics (CFD) simulations which, in the context of design optimization, may lead to challenges in finding optimum designs. This article draws attention to this issue by illustrating the difficulties it can cause for road vehicle aerodynamics simulations. Firstly, a benchmark probl...

Numerical noise is an inevitable by-product of Computational Fluid Dynamics (CFD) simulations which can lead to challenges in finding optimum designs. This article draws attention to the issue, illustrating the difficulties it can cause for road vehicle aerodynamics simulations. Firstly a benchmark problem is used to assess a range of turbulence mo...

The flow of droplets of bio-pesticide, liquid laden with entomapathogenic nematodes (EPNs), over foliage approximated as a planar substrate is investigated theoretically via a simple analytical model and computationally by solving a subset of the Navier-Stokes equations arising from application of the long-wave approximation. That the droplets of i...

The growth in demand for Information Technology (IT) systems and the requirements to better control carbon emissions is a large challenge for data centre design. Air-cooled data centres are becoming more efficient by layout and the adoption of compressor free cooling, but for higher densities, further efficiencies can be achieved with liquid (water...

Changing legislation and rising energy costs are bringing the need for efficient baking processes into much sharper focus. High-speed air impingement bread-baking ovens are complex systems using air flow to transfer heat to the product. In this paper, computational fluid dynamics (CFD) is combined with experimental analysis to develop a rigorous sc...

Metrics commonly used to assess the energy efficiency of data centres are analysed through performing and critiquing a case study calculation of energy efficiency. Specifically, the metric Power Usage Effectiveness (PUE), which has become a de facto standard within the data centre industry, will be assessed. This is achieved by using open source sp...

This article presents a formal optimization study of the design of small livestock trailers, within which the majority of animals are transported to market in the UK. The benefits of employing a headboard fairing to reduce aerodynamic drag without compromising the ventilation of the animals’ microclimate are investigated using a multi-stage process...

Changing legislation and rising energy costs are bringing the need for more efficient baking processes into much sharper focus. High-speed air impingement bread-baking ovens are complex systems used to entrain thermal air flow. In this paper, Computational Fluid Dynamics (CFD) is combined with a multi-objective optimization framework to develop a t...

Energy usage in bread ovens is analysed using a generic methodology applicable to all types of mass-production tunnel ovens. The presented methodology quantifies the energy required to bake the dough, and to conduct a detailed analysis of the breakdown of losses from the oven. In addition, a computational fluid dynamics (CFD) optimisation study is...

In the design of a data centre (DC), engineers are increasingly using specialized commercial computational fluid dynamics (CFD) software packages to predict thermal loads for various cooling configurations. This paper is the first to demonstrate how a set of open source software tools, namely OpenFOAM, Octave and paraview can be used to simulate an...

The authors have discovered an error on page 4 in text following Eq. (6). The error is in the text: “…the Reynolds number and St=rho*G_0*H_0/mu*U_0=2/sin(theta) the Stokes number…” The text should read: “…the Reynolds number and St=rho*G_0*H_0^2/mu*U_0=2/sin(theta) the Stokes number…”

The flow of a gravity-driven thin liquid film over a substrate containing topography, in the presence of a normal electric field, is investigated. The liquid is assumed to be a perfect conductor and the air above it a perfect dielectric. Of particular interest is the interplay between inertia, for finite values of the Reynolds number, Re, and elect...

This paper presents the first formal optimization study of the aerodynamic design of p olice van conversions . A flexible aerofoil - derived parameterization method is employed to d erive roof designs which minimize the deleterious aerodynamic effects of the compulsory front and rear light - bars . These are investigated using a formal optimization...

Supersonic jet pumps are simple devices with no moving parts, where a high velocity (primary) flow is used to pump a second fluid. In this paper, Computational Fluid Dynamics (CFD) is combined with an optimization framework in order to develop a tool for the rapid generation of jet pump designs. A key feature of the problem formulation is the trans...

Experimental and computational fluid dynamics (CFD) analyses of the thermal air flow distribution in a 3-zone small scale forced convection bread-baking oven are undertaken. Following industrial bread-making practise, the oven is controlled at different (constant) temperatures within each zone and a CFD model is developed and validated against expe...

Relying on thermal air management in a data centre is becoming less effective as heat densities from the Information Technology (IT) equipment continue to rise. Direct liquid cooling is more efficient at transferring the waste heat, but requires liquid loops passing as close as possible to the heat source. A new Computational Fluid Dynamics (CFD) s...

The problem of gravity-driven film flow over trench topography is investigated via novel solutions of the governing three-dimensional Navier-Stokes system of equations based on a finite element formulation, with the free surface parametrisation employing the method of spines. The resulting numerical analogue is solved using a parallel multifrontal...

Drying processes have been with us for a long time. During the Roman Empire, for example, the sun was used as a heat source in the convective drying of bricks, while during the industrial revolution, moist ceramic products were carried into and out of steam heated rooms by child labourers since it was deemed more cost effective to maintain a consta...

The comparative efficiency of time-splitting and multigrid schemes for the solution of lubrication models of three-dimensional (3D), thin film flow is demonstrated via detailed comparisons for benchmark gravity-driven continuous film and droplet spreading problems. Data are presented which show the effect of (1) problem formulation (either as a sin...

This paper describes, in the main, the benefits of using a general Newton globally convergent solver within an adaptive multigrid framework for solving discretised forms of lubrication models of three-dimensional, free-surface flow over and/or past substrate topography, involving complex physics. The two illustrative gravity-driven problems conside...

Jet pumps have a wide variety of applications and are commonly used in thermal power plants and refrigeration systems. An initial jet-pump design was developed using an analytical approach and its efficiency was improved using an efficient and accurate computational fluid dynamics model of the compressible turbulent flow in the pump, whose predicti...

Gravure roll coating is a technique used to coat fluids of a wide range of viscosities (up to 1500mPa s)onto substrates at speeds of up to 900 m/min (Booth,1970,1990). Coat thicknesses in the range of less than 1 micron up to 50 microns can be achieved, making this a versatile process which is finding application across a growing number of market s...

The dynamics of continuous thin film flow over flexible substrate is explored. Lubrication theory is employed to model the flow, resulting in a system of coupled equations for film thickness, pressure and substrate deflection which are solved numerically subject to appropriate boundary conditions. This is achieved accurately and efficiently using a...

Thin liquid film flow over surfaces containing complex multiply connected topography is modelled using lubrication theory. The resulting time dependent nonlinear coupled set of governing equations for film thickness and pressure is solved on different parallel computing platforms using a purpose written portable and scalable parallel multigrid algo...

Alternative lubrication and depth-averaged formulations of the unsteady Navier–Stokes equations are used to explore the problem of gravity-driven inertial thin film flow on substrates containing topography that is either fully submerged or protrudes through the film. The resulting discrete form of the equation sets are solved using a multigrid stra...

Genetic programming (GP) is a relatively new metamodelling technique, able to generate an explicit mathematical expression describing the relationship between the input variables and the modelled response. Despite the advantages given by its transparency, GP is still not widely used in optimisation. This paper presents a novel approach to boost GP...

Iso-octane, injected at high pressure into ambient nitrogen with different prescribed nearly isotropic turbulence levels, characterized by the root-mean-square (RMS) turbulence velocity, is explored experimentally. Mie scatter laser sheet and Schlieren techniques are combined with a high-speed camera to capture images of the vapor and liquid phases...

The three-dimensional flow of a gravity-driven continuous thin liquid film on substrates containing micro-scale features is modelled using the long-wave lubrication approximation, encompassing cases when surface topography is either engulfed by the film or extends all the way though it. The discrete analogue of the time-dependent governing equation...

A range of problems is investigated, involving the gravity-driven inertial flow of a thin viscous liquid film over a planar surface containing topographical features, modelled via a depth-averaged form of the governing unsteady Navier-Stokes equations. The discrete analogue of the resulting coupled equation set, employing a staggered mesh arrangeme...

Increasing societal and governmental concern about the worldwide use of chemical pesticides is now providing strong drivers towards maximising the efficiency of pesticide utilisation. There is growing recognition that the ultimate goal of achieving efficient and sustainable pesticide usage will require greater understanding of the fluid mechanical...