Mechanical Engineering research impact

Hello, my name is Salman and I'm a research fellow at the University of Birmingham. Hydrogen is being discussed as a potential decarbonization pathway, and the most space efficient storage method for hydrogen has emerged as liquid hydrogen. The liquefaction of hydrogen requires a lot of energy to be input into the system. But when hydrogen is utilised in the internal combustion engine or fuel cells, it must be regassified. During the regasification process, all the cold cryogenic exergy is wasted due to regasification. And this test rig here is a dual waste energy reutilisation organic Rankine cycle that utilises the waste thermal energy from the combustion. The waste heat from the combustion or from fuel cell operation in the evaporator., and then reutilises the cryogenic exergy in the condenser. So we have cryogenic working fluids that are pressurized by the pump. And then the high pressure cryogenic liquid goes to the evaporator where it absorbs the heat from the waste heat energy source and turns into superheated vapour. The high pressure superheated vapour then goes to the expander, produces power, and the low pressure vapour then goes to the condenser, where it reutilises the waste cryogenic energy. Here in the lab, we have liquid nitrogen as the cryogenic cooling source. Thank you.

Disruptive power technologies are highly desired in order to get hydrogen or ammonia as zero carbon fuels and minimise NOx emissions. A novel linear engine prototype has been developed with the potential to compete with fuel cell technology in terms of emissions and efficiency. This linear engine generator test-rig has been developed in order to characterise the linear generator performance. You can find in the central part of this test-rig, the linear generator flanked by compressors and expanders and at both ends you can find the linear valve variable actuation systems. Basically the linear generator  structure is made by a tubular housing in which a magnetic piston flows. So the kinetic energy from the engine piston is going to be transferred to the magnetic piston. And due to the magnetic flux change, we would see an induced current in the housing coils. The latest experiments on this test-rig has shown a power of about 2 Kilowatt with an overall global efficiency of 50%within an operative frequency of 16 hertz. This prototype is also intended to be scaled up to a megawatt size using an external combustor burning the ammonia and hydrogen as main fuel. And performing full closed loop joule cycle with argon or helium as working gas. Thank you.

Our swirl-enhanced optical combustor. The fundamental combustion characteristic of hydrogen and hydrogen carrying fuels such as ammonia and methanol, are crucial for advancing the design of burner engines and gas turbines. The swirl-enhanced optical combustor test rig is designed especially to study these combustion properties and is integrated with HORIBA, combustion and a Thermo Fisher Emission Analyser to detect a broad range of emissions including CO2, NOx,O2,hydrocarbon, ammonia slip, and unburnt hydrogen. The optical combustor is a ten kilowatt cylindrical chamber featuring four-sided detachable quartz glass windows, with and an inner chamber of150 mm in diameter and 310 mm, in length. The combustor head includes an air swirler and an eight hole fuel nozzle, to allow the fuel injection at adjustable angles to enhance the fuel-air mixing. It also a feature with five probe points to measure the inner wall temperature and detect heat flux. For the optical diagnostics, the setup uses a high-speed phantom camera paired with a Hamamatsu Photonics image intensifier to capture low-light chemiluminescence enabling OH* chemiluminescence imaging during combustion test. Additionally, the combustor is also equipped with a planar laser induced fluorescence(PLIF)to visualise and measure concentration fields, temperature, and flow characteristics. These optical diagnostic methods provide a non-invasive cost-effective insight into hydrogen and hydrogen carrying fuel combustion processes. Thank you.

The Spray Lab focuses on advancing our understanding of fuel spray characteristics and developing fuel injectors for next generation sustainable engines. Current research aims to provide fundamental experimental data to uncover the core principles of Hydrogen and Ammonia spray and combustion across various applications. The lab is occupied with a Pressure Control Constant Volume Vessel,  a key tool for high precision optical diagnosis of fuel spray behaviour and flame propagations. The 15 litre vessel is outfitted with a large circular optical window enable Schlieren based visualization. A high speed camera is paired with this set up to capture a detailed, real time dynamic of fuel spray at high resolution. The vessel can simulate a wide range of environmental conditions, including high pressure and temperature, with the heating element inside and the nitrogen regulating the internal back pressure. Beyond fuel investigation, the vessel is versatile enough for pre-mix combustion studies, such as analysing flame speed and propagation. Precise control over mass flow rateis achieved using the flow control unit, which regulates the amount of Hydrogen, Ammonia, or Methane introduced into the vessel. Once the fuel mixture is prepared, it is ignited by a centrally positioned spark plug. The high speed Schlieren diagnostic system captured propagation of the resulting spherical flame, enabling a detailed study of the flame dynamics under various fuel mixture, air-fuel ratios and conditions. Thank you.