Comparative study on effect of blending,thermal barrier coating (LHR) and injector nozzle geometry on biodiesel-fuelled engines

Increased petroleum prices, increased threat to the environment from exhaust emissions and global warming have generated intense international interest in developing renewable and alternative non-petroleum fuels for internal combustion engines. Evolving suitable technology for addressing energy crisis creates a continued investigation into the search for sustainable and clean-burning renewable fuels. This work investigates suitability of different non-edible-derived biodiesels such as cotton seed oil methyl ester (COME), Honne oil methyl ester (HnOME) and Rubber seed oil methyl ester (RuOME) to four stroke, single cylinder compression ignition (CI) engine. Engine tests were conducted to study the effect of fuel blending, thermal barrier coating (TBC) or Low Heat Rejection (LHR) and injector nozzle geometry on the performance, combustion and emission characteristics of COME, HnOME and RuOME in the modified CI engine. Blends of biodiesels with diesel were varied from 20 to 80% in steps of 20%. Two thermal barrier coatings of partially stabilized zirconium (PSZ) and aluminium oxide (Al₂O₃) were provided on the engine to make it fully adiabatic. Nozzle injectors of 3, 4 and 5 holes, with size of orifice varied from 0.2 to 0.3 mm size were selected for the study. It was concluded that B20 biodiesel blend, PSZ-coated engine and four hole nozzle injector of 0.2 mm size resulted in overall better engine performance with increased brake thermal efficiency (BTE) and reduced HC, CO, smoke emissions for the fuel combinations tested. Combustion analysis to study the effect of biodiesel blends, LHR coatings, injector nozzle geometry on the performance of the biodiesel-fuelled engine has been presented to give more insight into the behaviour of operation.     

Development and characterization of microwave composite cladding

The development of cladding through microwave radiation is recently explored and very few, initial studies were reported elsewhere. In order to explore more viability of process, (EWAC (Ni based) + 20% Cr₂₃C₆ powder) composite cladding has been developed on substrate austenitic stainless steel (SS-316). The experiments were conducted in domestic microwave oven and the clad of thickness, approximate 500 m has been developed by the exposure of microwave radiation at frequency 2.45 GHz for duration of 360 s. Typical clads cross sections of composite clads showed good metallurgical bonding with the substrate by partial dilution. The back scattered electron image of clad cross section showed the reinforced chromium carbide (Cr₂₃C₆) particles are uniformly distributed and well embedded in the Ni based matrix. The developed clad is free from visible solidification cracking and has significantly less porosity which is of the order of 0.90%. The XRD pattern of the developed clad showed the presence of FeNi₃, NiSi and Cr₂₃C₆ phases. The average Vicker's microhardness of developed clad was observed as 425 ± 140 Hv.     

Cost effectiveness of recycling: A systems model

Financial analytical models of waste management systems have often found that recycling costs exceed direct benefits, and in order to economically justify recycling activities, externalities such as household expenses or environmental impacts must be invoked. Certain more empirically based studies have also found that recycling is more expensive than disposal. Other work, both through models and surveys, have found differently. Here we present an empirical systems model, largely drawn from a suburban Long Island municipality. The model accounts for changes in distribution of effort as recycling tonnages displace disposal tonnages, and the seven different cases examined all show that curbside collection programs that manage up to between 31% and 37% of the waste stream should result in overall system savings. These savings accrue partially because of assumed cost differences in tip fees for recyclables and disposed wastes, and also because recycling can result in a more efficient, cost-effective collection program. These results imply that increases in recycling are justifiable due to cost-savings alone, not on more difficult to measure factors that may not impact program budgets.