Multi-objective optimization of CRDI engine characteristics powered with Mahua methyl ester/diesel blend: a Taguchi fuzzy approach.

An investigation has been conducted on a CRDI (common rail diesel injection) engine utilizing a blended fuel using mahua methyl ester to explore the influence of fuel injection strategies (i.e., FIP, CR, and FIT) on the engine characteristics. It is observed that specific fuel consumption (BSFC) and nitrogen oxide emission (NOx) increased with a decrease in brake thermal efficiency (BTE) in the case of MME100 at a base FIP of 500 bar. The volatility and viscosity (physical properties) of the MME fuel blend influenced the combustion phenomena resulting in a reduction in engine performance. The higher viscosity of the methyl ester blend restricts the fuel atomization process during the injection. Fuel injection pressure (Pinj) was raised from 500 to 1000 bar in increments of 250 bar in the first phase to maximize the use of the MME blend. High injection pressures (1000 bar) have higher BTE (12.33%) and better combustion characteristics (2.86%) than lower fuel injection pressures (500 bar). The concentrations of smoke (3.62%), CO (15.6%), and HC (2.8%) were reduced as injection pressure was raised, owing to the better formation of the mixture and improved spray atomization. Better results were obtained by optimizing and confirming operational parameters such as compression ratio, injection pressure, and injection time. This optimum value of 1000 bar injection pressure, injection timing of 27° bTDC, and a compression ratio of 18: 1 is utilized as the operating parameter values in the subsequent experiments to improve performance and decrease emissions while utilizing MME biodiesel blends in a CRDI engine.

Investigating the role of fuel injection pressure and piston bowl geometries to enhance performance and emission characteristics of hydrogen-enriched diesel/1-pentanol fueled in CRDI diesel engine.

This paper deals with the effects of piston bowl geometry (hemispherical bowl, troded bowl, and re-entrant bowl) and fuel injection pressure (200 bar, 220 bar, and 240 bar) with hydrogen-diesel/1-pentanol (B20 (80% diesel and 20% pentanol) + 12 lpm of hydrogen) on the emission, combustion, and performance characteristics of a common rail direct injection diesel engine. Re-entrant bowl outperforms hemispherical and troded bowl in terms of brake thermal efficiency (5.67%) and hydrocarbon (8% reduction) with an increase in the fuel injection pressure (240 bar) at part and full load. However, with the increase in the fuel injection pressure in the re-entrant bowl, a slight reduction in nitrogen oxide emissions (2%) is observed. With an increase in injection pressure in the case of re-entrant bowls, NHRR (net heat release rate), peak pressure (in-cylinder), and ROPR (rate of pressure rises) all rise significantly by 3.4%, 4.2%, and 2.3%. It is found that changing the piston shape and fuel injection pressure simultaneously is a potential alternative for improving engine performance and lowering emissions.

Influence of fuel injection timing and trade-off study on the RCCI engine characteristics of Jatropha oil-diesel blend under 1-pentanol dual-fuel strategies.

The current study deals with a reactivity-controlled compression ignition (RCCI) engine working with 1-pentanol as the LRF and JOBD as the HRF. The composition of the pilot fuel includes 20% Jatropha oil and 80% diesel, which nearly matches the heating value and cetane index of petroleum diesel. The research focuses on studying the impact of the pilot fuel injection angle on the engine characteristics at full load conditions, and the pilot fuel injection angle varies from 19, 21, 23, 25, to 27° bTDC at a constant injection pressure of 600 bar. The results revealed that increasing the pilot fuel injection angle increased the engine performance with a 13.36% rise in BTE, a reduction in CO emissions by 11.03%, and a decrease in HC emissions by 9.28% at a pilot fuel injection angle of 25° bTDC at 30% pentanol energy share (BD70P30). On the other hand, NOx emissions rise by 11.07%. The results indicate that the performance of the ternary fuelled RCCI engine can be improved by increasing the fuel injection angle of the pilot fuel.

Multi-objective optimisation of engine characteristics of an RCCI diesel engine powered with Jatropha/1-pentanol blend: a Taguchi-fuzzy approach.

Researchers are examining the possibilities for alternative fuel research as a fossil fuel replacement in light of global energy insecurity and other urgent challenges like global warming, severe emissions, and growing industrialization. This research uses 1-pentanol as a low reactivity fuel and Jatropha biodiesel as a high reactivity fuel to explore the reactivity-controlled compression ignition engine characteristics. A water-cooled single-cylinder engine is used in an experiment with varied loads of 25%, 50%, and 75% at a constant speed of 2000 rpm to examine the effects of operational parameters (i.e., (23 bTDC, 25 bTDC, and 27 bTDC) and (400 bar, 500 bar, and 600 bar)). The fuzzy-based Taguchi approach predicts operational parameters, including fuel injection time, fuel injection pressure, and engine load. Utilizing this ideal model, one may increase brake thermal efficiency and braking power while minimizing unburned hydrocarbon and nitrogen oxide emissions. An L20 orthogonal array is used to analyze the effects of various variables on an engine running on B20/1-pentanol fuel, including engine load, fuel injection timing, and fuel injection pressure. Multiple models are generated and verified with the use of experimental findings. Compared to other operating parameters, for reducing oxides of nitrogen, hydrocarbons, and brake-specific energy consumption maximally, engine load of 75%, FIP of 400 bar, and FIT of 23 bTDC are optimal based on the greatest MPCI value of 0.802.

Computational analysis on solar air heater with combination of alternate dimple protrusions and intrusions on absorber plate with one rounded corner triangular duct.

This study focuses on improving heat transfer by converting one of the corners of the duct to a rounded structure. To study the effect of dimpled shaped protrusions and intrusions on the rounded corner triangular duct with a constant radius of curvature by varying relative streamwise distance (z/e) with a constant transverse distance x'/e = 10,14 and 18. Steady-state, turbulent flow heat transfer under thermal boundary conditions is to be analyzed by varying different Reynolds numbers (5600 to 21000). The duct with dimple-shaped protrusions and intrusions is compared with a simple triangular duct. Optimization of relative horizontal distance (z'/e) by keeping constant protrusion to protrusion distance as z/e = 28 and relative transverse distance as x/e = 10, 14, and 18. It was noted that there was a significant loss in friction and a rise in heat transfer. The relationship between friction factor and Nusselt number was formulated using operating and roughness parameters, using the data collected from the numerical investigation. The friction factor increases significantly with roughness elements, and it is maximum for x'/e = 20 at a low Reynolds number. Nusselt number increases with roughness elements, and it is maximum for x'/e = 14 for all Reynolds numbers and all the models. Enhancement of Nusselt number is due to increase of local heat transfer because of local vortex neat heat transfer zone. The maximum outlet temperature is obtained at a low Reynolds number. The maximum temperature of the heated surface is obtained for Rc = 0.67 h and the minimum for Rc = 0.33 h.

Effect Of n-amyl alcohol/biodiesel blended nano additives on the performance, combustion and emission characteristics of CRDi diesel engine.

This paper deals with the study on the influence of the effects of iron oxide nanoparticle additives when added to ternary fuel (diesel + mahua methyl ester + pentanol) on the emission, combustion, and performance characteristics of a four stroke, single cylinder, common rail direct injection diesel engine working at a constant speed and varying operating scenarios. Doping is done in various proportions to the nanoparticle additives with the help of a homogenizer and ultrasonicator where the cationic surfactant used is CTAB (cetyl trimethyl ammonium bromide). Iron oxide nanoparticles were used as additives in fuel in the dosages of 40 ppm, 80 ppm, and 120 ppm respectively and TF (ternary fuel) is obtained by mixing 10% pentanol, 20% mahua, and 70% diesel together is used for the experimental study. The experimental study revealed that while using the nanoparticle additives blended ternary fuel (i.e., TF80), the number of harmful pollutants like smoke (5.38%), HC (6.39%), carbon monoxide (10.24%), and NOx has reduced to a considerable extent and there was a commendable improvement in the BTE by 8.8%. So, we can summarize that when ternary fuel and nano additives are blended together the combustion and performance of the engine was improved considerably and pollutant emissions were decreased.

Influence of the effect of nanoparticle additives blended with mahua methyl ester on performance, combustion, and emission characteristics of CRDI diesel engine.

This research work aims to investigate the effect of fuel-borne additives when added to mahua methyl ester (MME) blend operated on common rail direct injection diesel engine. Nanoparticles (Al2O3 and Fe2O3) were chosen with the help of a homogenizer and ultrasonicator as fuel additives at dosing levels of 40, 80, and 120 ppm, respectively, and the biodiesel is prepared by blending 80% diesel and 20% MME. The performance, emission, and combustion characteristics were considered for analysis. The experimental study revealed that while using the Al2O3 nanoparticle additives' blended biodiesel (MME20+AONP120), the number of harmful pollutants like smoke (5.38%), HC (6.39%), carbon monoxide (10.24%), NOx, etc. has reduced to a considerable extent and there was a commendable improvement in the BTE by 8.8% in comparison with MME20. Moreover, MME20+AONP120 blend resulted in high in-cylinder pressure, HRR of about 58.4 bar, and 118 J/0CA, respectively, which are higher than diesel and MME20. So, it can be summarized that when biodiesel and nano additives are blended together, the combustion and performance of the engine were improved considerably and pollutant emissions were decreased.

An experimental assessment on the influence of high fuel injection pressure with ternary fuel (diesel-mahua methyl ester-pentanol) on performance, combustion, and emission characteristics of common rail direct injection diesel engine.

Optimization of fuel injection strategies can maximize the utilization of ternary fuel by addressing the issues concerning fuel consumption, engine performance, and exhaust gas emission. In the midst of the pervasiveness of plant-based biofuel, this paper focused on maximizing the mahua oil biodiesel usage in a diesel engine having a common rail direct injection (CRDI) system without any engine modifications. The crude oil extracted from the seeds of Madhuca longifolia is known in India as mahua butter and has shown impressive fuel properties such as lower viscosity, flashpoint, boiling point, and comparable calorific value to diesel. 1-Pentanol, which has a chain of five carbons and can easily be blended with both diesel and biodiesel, is a promising type of alcohol for the future. In this study, the influence of fuel injection pressure with ternary fuel (diesel + mahua methyl ester + pentanol) on engine characteristics of CRDI diesel engine was analyzed. The fuel injection pressure is varied from 20 to 50 MPa so that ternary fuel can be properly utilized. The high injection pressure of 50 MPa has better combustion characteristics and higher brake thermal efficiency (4.39%) value than other injection pressure values. A better mixture is formed due to well-atomized spray, and as a result, the levels of CO (22.24%), HC (9.49%), and smoke (7.5%) fall with the increase in injection pressure. The usage of ternary fuel raised the NOx emission (12.46%) value and specific fuel consumption (SFC) with a decrease in the BTE (brake thermal efficiency) which attributes to its properties and combustion characteristics.

Numerical analysis of nanomaterial-based sustainable latent heat thermal energy storage system by improving thermal characteristics of phase change material.

Thermal energy conversion and storage plays a vital role in numerous sectors like industrial processing, residential and mass cooking processes, thermal management in buildings, chemical heating, and drying applications. It will also useful in waste heat recovery operations in industrial/thermal power stations. The effect of Al2O3 nanoparticle volume fraction (0%, 2%, and 5%) in a paraffin phase change material (PCM) and heater location (Bottom and Sidewall) in a 2D square thermal energy storage system have been numerically analyzed in this study. Transient thermal analysis has been carried out in ANSYS Fluent R18.1 for 500, 1000, and 3000 s. Laminar flow conditions with an enthalpy porosity model are used to study the solidification and melting behavior of nano-PCM. A Grid independence test has been conducted and selected an optimum number of elements as 115538. The results revealed that the addition of nanoparticles in PCM improves its thermal characteristics. The variation of liquid fraction and temperature profile with time has been recorded, and this is due to Rayleigh-Benard convection. At a given time, the melting rate increases with an increase in nanoparticle concentration up to 2% insertion after that the melting fraction reduces for both bottom wall and sidewall heating. This is mainly due to viscous domination with the increase in physical characteristics like density and viscosity of the fluid. Also, the melting rate in the case of sidewall heating augmented more than the bottom wall heating due to negligible buoyancy effects in former than later. The outcome of this analysis helps to find out the optimum volume concentration of nanoparticles to maximize the thermal energy storage applications.