A comparative evaluation and optimization of performance and emission characteristics of a DI diesel engine fueled with n-propanol/diesel, n-butanol/diesel and n-pentanol/diesel blends using response surface methodology

Abstract

High carbon bio-alcohols have recently grabbed the attention of diesel engine researchers because of higher energy density, higher cetane number and better blend stability than their low carbon counterparts. This study utilizes three high carbon bio-alcohol/diesel blends prepared by mixing 40% by vol. of n -propanol, n -butanol and n -pentanol individually with fossil diesel in a DI diesel engine. Engine performance and emission characteristics were measured under high-load condition based on a 3 3 full-factorial experimental design matrix using exhaust gas recirculation (EGR) rate, injection-timing and alcohol type used in the blends as factors for controlling charge-dilution and combustion-phasing. A statistical investigation was then carried out to compare and analyze the effects of these factors on all measured responses like nitrogen oxides (NOx), smoke, hydrocarbons (HC), carbon monoxide (CO), brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC). Multiple regression models were developed for all responses using response surface methodology (RSM) and were found to be statistically significant at 99% confidence levels. Interactive effects between injection timing and EGR for all blends were compared and analyzed through response surface plots fitted using developed models with high R 2 values. Optimization was performed using desirability approach with an objective to minimize NOx, smoke and BSFC with maximum BTE. n-Propanol/diesel blend injected at 25° CA bTDC under 30% EGR with a desirability of 0.965 was predicted to be optimum for this engine. Similarly n-butanol/diesel and n-pentanol/diesel blends injected at 24°CA bTDC under 10% EGR were found to be optimum in their respective category. Confirmatory tests validated that the developed RSM models were adequate to describe the effects of injection timing and EGR on the engine characteristics as the predicted error is within 5%.

Utilization of Pentanol as Biofuels in Compression Ignition Engines

“…and Yilmaz et al (2016) also found that 10 and 20% pentanol/WCO biodiesel blends resulted in an improvement in BTE and a maximum of 2% increase in the BSFC. These findings are in agreement with the recent results by Mahalingam et al (2018) for 10 and 20% pentanol/Mahua oil methyl ester (MOME) blends and by Rajasekar (2016) for the Jatropha oil biodiesel/pentanol (B70B30) blend. However, in a single-cylinder water-cooled diesel engine fueled with Karanja oil biodiesel blends along with pentanol addition of 10 and 20% by volume (Jeyakumar and Narayanasamy, 2019), the BTE increased and BSFC decreased with binary blends.…”

“…CO and HC emissions of n-pentanol/WCO biodiesel blends are higher than those of diesel and biodiesel, particularly at low engine loads (Zhu et al, 2016). Similarly, Rajasekar (2016) found for Jatropha biodiesel/pentanol blends (B70P30) that smoke opacity and NOx emissions decreased while CO and HC emissions increased. Further, J70P30 resulted in lower CO, NOx, and PM emissions than J70BU30 (butanol) for all loads, while J70P30 produced higher HC emissions than J70BU30 for all loads.…”

Effect of di-tertiary-butyl peroxide additive on combustion, performance and emissions of a karanja methyl ester fueled diesel engine

“…In addition, increase in percentage of DTBP in KME lowers the ignition delay and enhances mixing of fuel and air. Consequently, the combustion rate is improved, which lowers the HC emissions (Kumar et al 2016). The above-depicted results are in harmony with the work of Devarajan et al…”

Explosion Characteristics of Propanol Isomer–Air Mixtures

“…Increasing attention has been paid to the use of non-petroleum-based fuels, preferably from renewable sources, including alcohols with up to five carbon atoms. These alcohols are successful in the practical use as gasoline and diesel fuel additives and this has motivated the full investigation of their combustion chemistry [1][2][3][4].…”

“…Presented and published explosion ranges (in vol.%). Institut für Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung, Sankt Augustin, Germany,2 International Labour Organization, Geneva, Switzerland,3 Society of Fire Protection Engineers, Gaithersburg, USA,4 Design Institute for Physical Property Research, Fort Washington, USA, 5 1P + 2P = 1-C 3 H 7 OH + 2-C 3 H 7 OH mixture for f = 0.5.…”