Decarbonizing heavy-duty vehicles is becoming increasingly important, yet multiple renewable-based decarbonization pathways have not been compared systematically. To fill this gap, this study develops a techno-economic and environmental model that integrates the fuel cycle and vehicle cycle to assess these pathways for China. The model includes two...
The ignition of spray flames is a process of stochastic nature, especially relevant to the highaltitude relight of aeroengines. The present work aims to quantify the role of spray inhomogeneities in a realistic droplet-laden ignition set-up through Direct Numerical Simulations (DNS). Computations of the ignition process of weakly turbulent ethanol ...
Laser-induced grating spectroscopy (LIGS) is applied, for the first time, to a swirling nonpremixed hydrogen–air flame in a high-pressure combustion facility. A portable LIGS unit is used to probe 35 different axial and radial locations in the flame, and a new conditioned processing approach based on laminar flame simulation is introduced t...
The structure of hydrogen-enriched methane-air flames in a Bunsen burner at low turbulence is investigated using OH planar laser-induced fluorescence (PLIF). Three flames are investigated at identical unstretched laminar flame speeds and turbulence conditions, while hydrogen enrichment is varied up to 70% by volume. An increase in global flame cons...
Hydrogen is a promising zero-carbon fuel for decarbonized energy and transportation sectors. While carbon emission is not a concern for hydrogen combustion, its higher adiabatic flame temperature poses challenges of mitigating thermal NOx emissions. The wide flammability limits of hydrogen allow a fuel-lean operation, which can reduce NOx emissions...
The oxidation of small particles (size 200 μm) of char from oak has been studied, by adding a small batch of them to an electrically heated bed of inert, silica sand, fluidised by mixtures of O2 and N2. The concentrations of CO, CO2, and O2, in the off-gases from the bed were continuously monitored, enabling the rate of combustion and also the frac...
We analyze 3D reconstructed surfaces based on previously reported high frequency measurements of flame edge location across expanding flames using Mie scatter. For the first time, principal curvatures of flame surfaces are estimated from eigenvalues of the second fundamental forms of the reconstructed surfaces, allowing the determination of the sta...
Many elastic systems localize under applied displacement, precipitating into regions of lower and higher strain; further displacement is accommodated by growth of the high strain region at a constant load. Such systems can be studied as propagating instabilities, focusing on the work required to propagate the high strain region, or as two-phase ene...
The mechanism of propagation close to flame-flame interaction events is analysed using direct numerical simulation of a turbulent premixed methane-air flame. Four canonical local topologies arising from flame-flame interaction are identified in the vicinity of critical points. These correspond to reactant pocket, tunnel closure, tunnel formation an...
Photovoltaics (PVs) are a critical technology for curbing growing levels of anthropogenic greenhouse gas emissions, and meeting increases in future demand for low-carbon electricity. In order to fulfil ambitions for net-zero carbon dioxide equivalent (CO2eq) emissions worldwide, the global cumulative capacity of solar PVs must increase by an order ...
