The use of composite materials, whether metallic or non-metallic, is becoming more popular nowadays because of some of their superior characteristics compared to the use of wood and metallic materials alone. From this perspective, a new natural fiber reinforced composite by varying the fiber orientation was developed in this study using coir and pineapple leaf fiber. This work uses the Taguchi method to investigate the different effects of control factors on mechanical and physical characteristics of the fabricated natural fiber-based composites. Various control factors were used, including fiber ratios, angles of orientation, and mat types. The testing was conducted in accordance with ASTM standards, and the results were validated through various statistical analyses including Taguchi orthogonal array analysis, confirmation tests, regression analysis, and analysis of variance (ANOVA). Based on the analysis and validation, the highest mean impact strength was found 53.93 J/cm², tensile strength 31.94 MPa, flexural strength 46.365 MPa, Rockwell hardness number 77, and lower water absorption rate only 3.62 %. From the confirmation test, margin of errors was found to be 4.84 %, 2.59 %, 2.35 %, 6.62 %, and 2.334 % for impact, tensile, and flexural strength, Rockwell hardness, and water absorption test respectively. The variation of the experimental and predicted results was observed from the regression analysis, and it was 2.93 to 0.4 J/cm², 2.12 to 0.79 MPa, 3.54 to 0.33 MPa, 2.33 to 0.8 RHN, and 0.92 %–0.13 % for impact, tensile, and flexural strength, Rockwell hardness, and water absorption test respectively. Overall, ANOVA analysis was used to examine the effects of different control variables, and it was discovered that the angle of orientation of fibers had a substantial impact on flexural strength and water absorption rate were 72.30 % and 70.89 % respectively. Similarly, mat types on tensile strength and Rockwell hardness with 46.47 % and 50.67 % respectively. In addition, the impact strength was most significantly affected by the wt.% ratio of fibers, which was approximately 50.32 %. From the above characteristics and their environmentally friendly behavior, these composites can be used in the place of synthetic fiber-based products.

This paper presents the design, fabrication, and performance test of a magnetic bearing employing no active components. In this study, the magnetic bearing was fabricated using a magnetic edge effect. Four large and three small hollow Neodymium (Nd) magnets were used of the same thickness, same internal diameter but different outer diameters. Small magnets were rigidly attached in the rotor and large magnets were fixed in the casing. In magnetic edge effects, a rotor along with small magnets was suspended inside the casing. Using stroboscope, rpm of the rotors were measured at no load, 0.5 N, 1.0 N, 1.5 N conditions for a different number of magnetic bearings in series, and the corresponding torque was calculated. After that, all the data were compared to the ball bearing set up in the same rotor. This paper shows that the speed of the magnetic bearing was doubled than the ball bearing with the same loading conditions. Required torque was 1.5 times greater in the case of ball bearing when compared to the magnetic bearing. The developed system is capable of suspending a rotor at a stable steady-state position. This suspension is accomplished by the edge effect of Nd round hollow magnets.

Energy demand is rising over time in both developing and developed countries. Therefore, finding new sources of energy is a prime concern now. For this effort, this paper presents the pyrolysis of onion (Allium cepa) shells in a reactor with a fixed bed for generating alternative liquid fuel. This paper also compares alternative fuel characteristics, including higher heating value, viscosity, density, pour point, and flash point, with conventional petroleum fuels at optimal process conditions. The work adopted pyrolysis to produce liquid fuel at a temperature range of 400–550 °C and utilized LPG to provide a heat source. The liquid product (fuel oil) was collected, and non-condensable gas was flared. The liquid product was tested for various properties, and the results of the analyses show that alternative fuel has a higher heating value of 12.227 MJ/kg, density of 800 kg/m³, viscosity of 4.3 cP at 30 °C, pour point below −6.2 °C, and flash point around 137 °C, with a variation due to the volatile matters. To obtain favorable conditions for pyrolysis, some parameters, including bed temperature, sample quantity, average particle size, and operating time, were varied and analyzed. The physio-chemical properties made the alternative fuels isolated from conventional petroleum fuels due to the variation in distillation temperature. This work shows that the fuel oil generated from the pyrolysis of onion shells could be considered an alternative source of fuel.

Exploring alternative fuels for internal combustion engines is now receiving much more attention to enhance the performance and reduce the pollutants from the engine. From this point of view, the blended fuels of pyrolytic plastic oil (PPO), diesel, and alumina (Al2O3) nanoparticles have been utilized in this study to investigate the effects of nanoparticles on Petter diesel engine performance and emission properties. During the blending of fuels through a magnetic stirrer and homogenizer, the ratio of PPO and diesel was varied in volume percentage at a step of 15% increment of PPO with 150 ppm of nanoparticles. From the experimental results, it has been observed that the blended fuel of PPO60D40A150 at 40N loading situation, exhibited the highest BTE of 23.90% as well as an increased BTE is obtained up to 2.65% compared to pure diesel at 21N loading condition. On the other hand, a reduction of BSFC and CO emission at 21N load, and NO emission at 40N loads has been observed of 16.07%, 39.38% and 62.04%, respectively. Among all the blended fuels, PPO60D40A150 has demonstrated an outstanding performance for BTE, BSFC, and NO emissions, while PPO45D55A150 has shown an impressive reduction of CO emissions. Overall, this study with different numerical values provides evidence that the addition of alumina (Al2O3) nanoparticles in the diesel engine fuels can remarkably enhance the performance and improve the emission properties of diesel engines.