Fuel spray vapour distribution correlations for a high pressure diesel fuel spray cases for different injector nozzle geometries

[EN] The evolution of diesel fuel injection technology, to facilitate strong correlations of in-cylinder spray propagation with injection conditions and injector geometry, is crucial in facing emission challenges. More observations of spray propagation are, therefore, required to provide valuable information on how to ensure that all the injected fuel has maximum contact with the available air, to promote complete combustion and reduce emissions. In this study, high pressure diesel fuel sprays are injected into a constant-volume chamber at injection and ambient pressure values typical of current diesel engines. For these types of sprays the maximum fuel liquid phase penetration is different and reached sooner than the maximum fuel vapour phase penetration. Thus, the vapour fuel could reach the combustion chamber wall and could be convected and deflected by swirling air. In hot combustion chambers this impingement can be acceptable but this might be less so in larger combustion chambers with cold walls. The fuel-ambient mixture in vapourized fuel spray jets is essential to the efficient performance of these engines. For this work, the fuel vapour penetration values are presented for fuel injectors of different k-factors. The results indicate that the geometry of fuel injectors based on the k-factors appear to affect the vapour phase penetration more than the liquid phase penetration. This is a consequence of the effects of the injector types on the exit velocity of the fuel droplets.Support for this work was provided by Ricardo UK, at Sir Harry Ricardo Laboratory in University of Brighton. Gratitude is also extended to: Prof. C. Crua, Dr. R. Morgan and Dr. G. de SerceyNjere, D.; Emekwuru, N. (2017). Fuel spray vapour distribution correlations for a high pressure diesel fuel spray cases for different injector nozzle geometries. En Ilass Europe. 28th european conference on Liquid Atomization and Spray Systems. Editorial Universitat Politècnica de València. 192-199. https://doi.org/10.4995/ILASS2017.2017.4951OCS19219

Regulation of Nanorefrigerant Use:A Proactive Measure Against Possible Undesirable Health and Environmental Implications

Recent research studies have shown the very high potentials nanotechnology application has in the refrigeration and air conditioning industry for improving the thermophysical properties of refrigerants and lubricants hence leading to systems with higher COP and much reduced size. The successes achieved with nanorefrigerants are connected to the improved technology for the preparation of nanofluids that has led to achieving more homogeneous and stable mixture of the base fluid and nanoparticle. However, available literatures point to the fact that nanoparticles can find its way into the human cells and as such is a potential health risk for humans and animals. At present, emphasis appears to concentrate more on the technological successes achieved with nanorefrigerants, like improved thermal conductivity, nucleate boiling and boiling heat transfer coefficient without factoring in much the potential health implications of adopting it. This paper therefore looked at the potential health consequences of adopting nanotechnology and called for an early regulatory framework to guard against any unforeseen health issues. Areas of future research were also suggested

Development of a framework for reduction of flare gas in an oil and gas processing environment

Gas flaring is a major contribution to global greenhouse gas burden with a total volume of 100 billion cubic meters (BCM) flared annually. Russia is responsible for 35.5 BCM annually while Nigeria burns 18.27 BCM, equated to approximately $2 billion yearly. There is urgent need to therefore conduct research aimed at management of gas flaring with large economic and environmental benefits. This study has developed a sustainable framework to manage flare gas, incorporating inputs from government, legislation, industrial partners that generate energy, and environmental monitoring and enforcement agencies towards achieving significant reduction in gas flaring. The research method used semi-structured interview of key practitioners in an oil and gas industry (GASPROC) to obtain useful data on gas produced and flared; as well as gas utilised in two case companies – (ELECPROC 1 and ELECPROC 2). Data obtained were analysed using NVIVO software, and the data highlighted details of volume of gas utilised to generate electricity, the amount of electricity generated, and the volume of flared gas. Overall, the case company (GASPROC) flared about 8.33% of its total annual gas production (6.6 million cubic meters). Study recommends that 50 units of gas turbine with gas consumption and electricity generation capacities of 0.93 MCM and 150 MW each would be sufficient to utilise the flare gas and produce 7500 MW of electricity daily. A capital investment of £1.64b will generate a net profit of £1.26b/year, with a rate of return of investment on 16.3%. It is anticipated that adoption and utilisation of the framework will significantly reduce the volume of flare gas with considerable economic and environmental benefits