Development of a very light rail vehicle

The collaborative very light rail project involves the development of a novel railcar designed to revolutionise the rail industry: a self-powered, Very Light Rail (VLR) vehicle. Each of the two bogies contains a complete diesel-electric series-hybrid drive system, whilst the whole vehicle has undergone significant lightweighting activity to realise a target weight of less than 18 tonnes, or 1 tonne per linear meter. The target cost is £500,000, which is to be achieved through the use of standardised, modular components, and appropriate materials and structural design methodologies. The research covers several aspects of the GB Rail Technical Strategy (RTS) chapter relating to Rolling Stock. Lightweighting leads to a reduction in the propulsion requirements and reduces the infrastructure installation and maintenance costs. The use of higher efficiency drive systems achieved through on-board energy systems enables a reduction in carbon emissions. These hybridisation activities improve the passenger experience through quieter operation, decreased vibration and the possible elimination of exhaust emissions in stations. Combining new drive systems with modular lightweight structures will lead to lower life-cycle costs and thus could enable the economical reopening of lines

Rail freight in 2035 - traction energy analysis for high-performance freight trains

This paper provides a comparison of the energy consumption and carbon emissions of rail and road vehicles for two routes. The scenarios considered are a high running speed container train, in locomotive hauled and electrical multiple unit (EMU) configuration, and a converted passenger EMU for pallets, as well as the corresponding road heavy goods vehicles. The container route is over the UK’s East Coast Main Line and the pallet route is from London to the border with Scotland. The well-to-wheel 2008 and projected 2035 energy figures and carbon emissions are determined. It is demonstrated that, despite higher running speeds, a modal shift to rail reduces carbon emissions. The higher speed results in a more flexible path allocation for freight trains, enabling more attractive and flexible offers to shippers, therefore encouraging modal shift. The particular advantage of rail in hauling large volumes of cargo is highlighted, particularly if locomotives are used for traction

Feasibility of discontinuous electrification on the Great Western main line determined by train simulation

The UK has a number of main line railway routes that are not yet electrified. Some of these routes are under active consideration for electrification and the UK Government has recently announced the electrification of the Great Western Main Line (GWML). Railway electrification requires a large capital investment in infrastructure. Areas with limited clearance, such as tunnels and sections through overbridges, are particularly expensive to electrify. In this paper, train performance on the GWML, from London Paddington to Cardiff and vice versa, is modelled for three cases: no electrification; full electrification; and electrification that does not include tunnels, most notably the Severn Tunnel. The modelled trains were: the High Speed Train hauled by pairs of Class 43 diesel-electric locomotives; the nine-car Class 390; and Intercity Express Programme (IEP) trains formed as straight electric or bi-mode multiple units. Bi-mode trains combine electric and diesel traction in the same train. The considered IEP trains included both five-car and eight-car bi-mode options. Journey time, energy consumption and CO2 emissions were determined in each case. Electrification of the route will result in a reduction in energy consumption, carbon emissions and journey time, with the longest trains offering the greatest benefit. Under normal conditions, all modelled trains were able to complete the journey under discontinuous electrification. However, a small reduction in entry speed into the Severn Tunnel resulted in stalling of the exclusively electric trains. Bi-mode rail vehicles completed the journey in all cases and, as to be expected, also when tunnel entry speed is reduced; journey time, energy consumption and carbon emissions are not majorly impacted compared to exclusively electric operation

Simulation Benchmark Based on the THAI-Experiment on Generation and Dissolution of a Light Gas Stratification by Natural Convection

Proceedings zur Conferenc

Development and design of a narrow-gauge hydrogen-hybrid locomotive

Hydrogen used as an energy carrier is a promising alternative to diesel for autonomous railway motive power, but, globally, few prototypes exist. In 2012, the Institution of Mechanical Engineers held the inaugural Railway Challenge, in which the participating teams had to develop, design and construct a locomotive to run on 10.25 inch (260.35 mm) gauge track while meeting certain set design criteria as well as competing in operational challenges. The University of Birmingham Railway Challenge Team’s locomotive design is described in this paper. The vehicle is the UK’s first hydrogen-powered locomotive and is called Hydrogen Pioneer. The drive-system consists of a hydrogen tank, a 1.1 kW proton-exchange-membrane fuel cell stack, a 4.3 kWh battery pack and two 2.2 kW permanent-magnet traction motors. The development of the locomotive, from the original concept to the final design, and the design validation are all presented in this paper. The locomotive completed successfully all challenges through which the proof of the concept of a hydrogen-hybrid locomotive was established

Functional Dominance of CHIP-Mutated Hematopoietic Stem Cells in Patients Undergoing Autologous Transplantation

Clonal hematopoiesis of indeterminate potential (CHIP) is caused by recurrent somatic mutations leading to clonal blood cell expansion. However, direct evidence of the fitness of CHIP-mutated human hematopoietic stem cells (HSCs) in blood reconstitution is lacking. Because myeloablative treatment and transplantation enforce stress on HSCs, we followed 81 patients with solid tumors or lymphoid diseases undergoing autologous stem cell transplantation (ASCT) for the development of CHIP. We found a high incidence of CHIP (22%) after ASCT with a high mean variant allele frequency (VAF) of 10.7%. Most mutations were already present in the graft, albeit at lower VAFs, demonstrating a selective reconstitution advantage of mutated HSCs after ASCT. However, patients with CHIP mutations in DNA-damage response genes showed delayed neutrophil reconstitution. Thus, CHIP-mutated stem and progenitor cells largely gain on clone size upon ASCT-related blood reconstitution, leading to an increased future risk of CHIP-associated complications