Globally, majority of great economies are fossil-fuel powered. Repercussions of such energy source monopolization are beginning to manifest in terms of global warming and climate change. Recently published studies have highlighted that combustion of fossil fuels at the current rate pose a threat to all living organisms; with particular adverse effects that lead to cancer, cardiovascular and respiratory diseases being attributed to internal combustion engines. A curative measure would be to overhaul the entire fossil-powered systems; however, time and cost implications would be untenable. A plausible alternative involves the adoption and incorporation of biofuels as they are ‘greener’ and have lower greenhouse gases output.
Over the years, global attention has been given to this matter with much concertation being the internal combustion engine. Application of thermal barrier coating has been reported as one of the modifications that could help curb greenhouse gases output. Thermal barrier coating application is a necessity since internal combustion components subjected to fuels other than fossil-based are subject to corrosion and consequent decline in performance.
To this effect, further investigations on approaches that could help implements biofuels without compromising the performance, integrity and energy output of internal combustions would be highly welcome. Indeed Kemal Masera (graduate student) and Dr. Dr Abul Kalam Hossain from Aston shared their critical expert opinion on engine tests results: performance, combustion and exhaust emission characteristics of the biofuels operated thermal barrier coating engines. Their goal was to demonstrate that thermal barrier coatings could potentially offset the performance drop due to use of biofuels in the compression ignition engines. Their review is currently published in the Journal of the Energy Institute.
In brief, the authors reviewed results previously reported in three scenarios: first, uncoated versus coated engine for fossil diesel fuel application; second, uncoated versus coated engine for biofuels (and blends) application, and finally, fossil diesel use on uncoated engine versus biofuel (and blends) use on coated engine. In addition, they assessed the effects of injection timing, injection pressure and fuel properties on thermal barrier coatings. Eventually, the material type, thickness and properties of the coating materials used by research community were presented.
The Aston university researchers pointed out that improvements of up to 4.6% in torque, 7.8% in power output, 13.4% in brake specific fuel consumption, 15.4% in brake specific energy consumption and 10.7% in brake thermal efficiency were reported when biofuels or biofuel blends were used in the thermal barrier coated engines as compared to the uncoated engines. Additionally, in coated engines, peak cylinder pressure and exhaust gas temperature were increased by up to 16.3 bar and 14% respectively as compared to uncoated condition.
In summary, effects of thermal barrier coatings on the compression ignition engine performance, combustion, and exhaust gas emissions characteristics were investigated when biofuels (and blends) were used instead of fossil diesel. Altogether, a total of 74 case studies from 28 literatures were reviewed and presented where engine characteristics results were grouped and tabulated based on various reference scenarios. Overall, the current review study by Kemal Masera and his PhD supervisor Dr. Dr Abul Kalam Hossain showed that application of thermal barrier coatings in compression ignition engines could be beneficial when biofuels or biofuel blends are used instead of standard fossil diesel.
K. Masera, A.K. Hossain. Biofuels and thermal barrier: A review on compression ignition engine performance, combustion and exhaust gas emission. Journal of the Energy Institute, volume 92 (2019) 783-801.Go To Journal of the Energy Institute