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The development of advanced thermal barrier coating (TBC) materials with better hot corrosion resistance, phase stability, and residual stresses is an emerging research area in the aerospace industry. In the present study, four kinds of TBCs, namely, single-layer yttria-stabilized zirconia (YSZ), single-layer gadolinium zirconate (GZ), bilayer gadolinium zirconate/yttria-stabilized zirconia (YSZ/GZ), and a multilayer functionally graded coating (FGC) of YSZ and GZ, were deposited on NiCrAlY bond-coated nickel-based superalloy (Inconel 718) substrates using the atmospheric plasma spray technique. The hot corrosion behavior of the coatings was tested by applying a mixture of Na2SO4 and V2O5 onto the surface of TBC, followed by isothermal heat treatment at 1273 K for 50 h. The characterization of the corroded samples was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) to identify physical and chemical changes in the coatings. GIXRD was used to analyze the residual stresses of the coatings. Residual stress in the FGC coating was found to be −15.2 ± 10.6 MPa. The wear resistance of TBCs is studied using a linear reciprocating tribometer, and the results indicate that gadolinium zirconate-based TBCs showed better performance when deposited in bilayer and multilayered functionally graded TBC systems. The wear rate of as-coated FGC coatings was determined to be 2.90 × 10−4 mm3/Nm, which is lower than the conventional YSZ coating. [ABSTRACT FROM AUTHOR]

The novelty of this research aims to attain low‐temperature combustion with the help of reactivity controlled compression ignition (RCCI) in a single cylinder, four‐stroke diesel engine by premixing the low reactivity fuel (LRF) such as 1‐hexanol with air in the intake manifold along with high reactivity fuel (HRF) such as neem oil methyl ester in the volumetric ratio of 80:20 (B20) as a primary fuel. HRF has been utilized as a primary fuel through the main injector along with the manifold injection of LRF fuel through a secondary injector at various energy shares, such as 10%, 20%, 30%, and 40%, and the fuel combinations were designated as B20HI10, B20HI20, B20HI30, and B20HI40. The readings were noted from no load to full load and the experiment showed that the brake thermal efficiency (BTE) was increased in RCCI mode up to 30% 1‐hexanol share compared with B20 due to its better combustion, which was evident by higher heat release rate (HRR); beyond 30%, there was a drop in BTE due to the reduction in pilot fuel quantity. Oxides of nitrogen and smoke were significantly reduced for all combinations in RCCI mode, whereas hydrocarbon and carbon monoxide emissions were increased substantially. A substantial increase in peak pressure and HRR was noticed in RCCI mode compared with conventional mode due to its better homogeneity and prolonged ignition delay. From the findings, this research suggests that B20‐1‐hexanol combinations in RCCI mode can be an attractive replacement for diesel fuel. [ABSTRACT FROM AUTHOR]

Due to the high prospective of rice bran oil, it can be used as a resource for biodiesel production. This study aims to produce high-quality rice bran biodiesel through enzymatic transesterification using lipase enzyme. The fuel properties are tested with standard protocols. Three explicit blends B20, B40, and B40 on v/v basis are prepared for the test purpose. With the CI engine test, the performance characteristics brake thermal efficiency and brake specific fuel consumption are arrived and compared with pure diesel. The emissions of CO, NOx, and HC are also analyzed. Test outcomes uncovered that the blend with lower biodiesel content performed well in the engine with brought down CO, HC and NOx outflows. In any case, with the higher biodiesel concentrations, there was a significant increment in the emission range. By and large, b20 and b40 blend brought about improved performance with limited emissions and can be used in an unmodified diesel engine. [ABSTRACT FROM AUTHOR]

Ever increasing energy demand ever encourage for new energy production and conservation. In the present work, the cascaded latent heat solar thermal energy storage system has been developed to deliver the heat at different temperature limits and its performance on the improvement of heat transfer characteristics are studied with the use of multiple phase change material (PCM) with various encapsulation arrangements. The storage system consists of three different PCM which have different melting temperatures such as D-mannitol, D-sorbitol, and paraffin wax. Each PCM is encapsulated in different materials of spherical balls like copper, aluminum, and brass. Permanent welding of fins, inside the encapsulated balls of type rectangular, annular and pin is done for enhanced heat transfer. This work investigates for the best combination of fins which may allow the highest heat transfer rate for the least cost. It has been concluded that the transfer of energy is the highest in the use of copper balls for encapsulation of PCM with the attachment of annular fin inside the balls. With respect to energy cost per kJ of heat transfer, the PCM encapsulated in aluminum balls with annular fins may be preferred. However, in all the combinations, to gain higher efficiency of the system proper arrangements of all system components very close to each other is essential to the provision of perfect insulated storage tanks and the components of the piping circuit. [ABSTRACT FROM AUTHOR]