Impact of pilot diesel injection timing on performance and emission characteristics of marine natural gas/diesel dual-fuel engine.

In diesel-ignited natural gas marine dual-fuel engines, the pilot diesel injection timing (PDIT) determines the premixing time and ignition moment of the combustible mixture in the cylinder. The PDIT plays a crucial role in the subsequent development of natural gas flame combustion. In this paper, four PDITs (- 8 °CA, - 6 °CA, - 4 °CA, and - 2 °CA) were studied. The results show that the advancement of PDIT increased the engine's power, thermal efficiency, and natural gas flame spread velocity, and increased NO emissions and CH4 emissions of the marine engine. The PDIT affected the ignition delay period and the rapid combustion period to a greater extent than the slow combustion period and the post combustion period. With each 2 °CA advancement of PDIT, the engine's power increased by 69.87 kW, thermal efficiency increased by 0.42%, radial flame spread velocity increased by 2 m/s, axial flame spread velocity increased by 1.7 m/s, NO emissions increased by 6.1%, and CH4 emissions increased by 3.75%.

Kinetic modeling of ion formation during diesel combustion with different fuel injection timing.

Ions are formed during the combustion process in internal combustion engines. The measurement of ions inside the combustion chamber produces reliable information about the combustion process. The present study focuses on the formation of ions inside the combustion chamber of diesel engines with different injection timing. For this purpose, a multi-zone thermodynamic model is utilized to simulate the closed cycle of the engine. To understand the kinetic behavior of the ions, the model is connected to an ionic chemical kinetics mechanism with 336 reactions and 81 species. Six important ionic reactions comprising 5 ions are used in the ionic mechanism. Dvode differential equation solver is also employed to calculate the energy and kinetics equations. The developed model has an acceptable accuracy in predicting the performance and pollutants of diesel engines. Based on the results, the ion formation is delayed by delaying the fuel injection timing. The maximum amount of in-cylinder ions depends on injection timing. In-cylinder ion current can predict the start of combustion accurately.

Energizing tomorrow: unleashing spirulina's potential in engine performance optimization and emission reduction.

Dwindling of fossil fuels and the global climate change has prompted civilization to look into alternate energy sources. This has led to explore inexhaustible and sustainable resources in the domain of renewable energy. Among all sources renewable energy, biofuel produced from biomass has great prospect for energy security as well as environmental safety over fossil fuels. The present work tries to explore the performance attributes and emission characteristics of a CI engine utilizing spirulina microalgae biodiesel blend comprising of 20% algae biodiesel blended with 80% diesel. This blend is tested in a diesel engine at varying engine load conditions of 20%, 40%, 60%, 80%, and 100% at variable injection timing of 20°, 23°, 25°, and 28° bTDC, respectively at compression ratio of 18. Based on experimental results, the peak brake thermal efficiency for injection timing of 20°, 23°, 25°, and 28° bTDC at 100% engine load were observed to be 26.79%, 23.77%, 24.77%, and 25.09%, respectively for the biodiesel blend in comparison to 27.76% of diesel mode whereas the emissions levels were found to minimum at 20° bTDC. On the part of emission, the average drop in CO emissions for injection timing of 20°, 23°, 25°, and 28° bTDC were found to be 53.46%, 43.71%, 44.34%, and 50.31%, respectively for biodiesel blend as compared to diesel mode. For the same setting, in comparison diesel mode, the average fall in HC emissions were found to be 42.32%, 34.13%, 30.37%, and 37.54%, respectively, and the rise of NOx emissions were found to be 8.06%, 5.55%, 3.51%, and 3.04%, respectively. Response surface methodology was applied for optimization of operating parameters of the algae biodiesel blend run diesel engine. The desirability based study revealed that at 85.19% engine load and injection timing of 20° bTDC were optimal operation settings which resulted in engine performance of 25.44% brake thermal efficiency. The emission level at this setting was observed to be reduced to 27.68 ppm CO, 1.60% CO2, 24.65 ppm HC, and 182.15 ppm NOx.

Effects of klotho protein or klotho knockdown in porcine oocytes at different stages.

Klotho is a protein that plays different functions in female fertility. We have previously reported that klotho protein supplementation during in vitro maturation improves porcine embryo development, while klotho knockout for somatic cell cloning completely blocks full-term pregnancy in vivo. However, the effects of the microinjection of klotho protein or klotho knockdown dual vector in porcine embryos at different time points and the specific molecular mechanisms remain largely unknown. In this study, we injected the preassembled cas9 + sgRNA dual vector, for klotho knockdown, into the cytoplasm of the germinal vesicle stage of oocytes and into porcine embryos after 6-h parthenogenetic activation. Similarly, the klotho protein was inserted into the cytoplasm of germinal vesicle stage oocytes and porcine embryos after 6-h parthenogenetic activation. Compared with the controls, the microinjection of klotho dual vector markedly decreased the blastocyst formation rates in germinal vesicle stage oocytes and activated embryos. However, the efficiency of blastocyst formation when klotho protein was inserted before in vitro maturation was significantly higher than that after klotho protein insertion into parthenogenetically activated embryos. These results indicated that klotho knockdown may impair embryo development into blastocyst irrespective of injection timing. In addition, klotho protein injection timing in pig embryos may be an important factor for regulating embryo development.

Optical characterization of stratified-premixed natural gas direct-injection combustion regimes.

Gaseous fuels for heavy-duty internal combustion engines provide inherent advantages for reducing CO2, particulate matter (PM), and NOX emissions. Pilot-ignited direct-injected NG (PIDING) combustion uses a small pilot injection of diesel to ignite a late-cycle main direct injection of NG, resulting in significant reduction of unburned CH4 emissions relative to port-injected NG. Previous works have identified NG premixing as a critical parameter establishing indicated efficiency and emissions performance. To this end, a recent experimental investigation using a metal engine identified six general regimes of PIDING heat release and emissions behavior arising from variation of NG stratification through control of relative injection timing (RIT) of the NG with respect to the pilot diesel. The objective of the current work is to provide comprehensive description of in-cylinder fuel mixing of direct injected gaseous fuel and its impacts on combustion and pollutant formation processes for stratified PIDING combustion. In-cylinder imaging of OH*-chemiluminescence (OH*-CL) and PM (700 nm), and measurement of local concentration of fuel is considered for 11 different RIT , representing 5 regimes of stratified PIDING combustion (performed with P inj = 22 . 0 MPa and ϕ = 0 . 63 ). The magnitude and cyclic variability of premixed fuel concentration near the bowl wall provides direct experimental validation of thermodynamic metrics ( RI T premix , SO I NG , trans , RI T * ) that describe the fuel-air mixture state of all 5 regimes of PIDING combustion. The local fuel concentration develops non-monotonically and is a function of RIT. High indicated efficiency and low CH4 emissions previously observed for stratified-premixed PIDING combustion in previous (non-optical) investigations are due to: (i) very rapid reaction zone growth ( > 45 m/s) and (ii) more distributed early reaction zones when overlapping pilot and NG injections cause partial pilot quenching. These results connect and extend the findings of previous investigations and guide the future strategic implementation of NG stratification for improved combustion and emissions performance.

Heat release rate and emissions regimes of stratified pilot-ignited direct-injection natural gas combustion.

Natural gas (NG) is an attractive fuel for heavy-duty internal combustion engines because of its potential for reduced CO2, particulate, and NOX emissions and lower cost of ownership. Pilot-ignited direct-injected NG (PIDING) combustion uses a small pilot injection of diesel to ignite a main direct injection of NG. Recent studies have demonstrated that increased NG premixing is a viable strategy to increase PIDING indicated efficiency and further reduce particulate and CO emissions while maintaining low CH4 emissions. However, it is unclear how the combustion strategies relate to one another, or where they fit within the continuum of NG stratification. The objective of this work is to present a systematic evaluation of pilot combustion, NG combustion, and emissions behavior of stratified-premixed PIDING combustion modes that span from fully-premixed to non-premixed conditions. A sweep of the relative injection timing, RIT , of NG and pilot diesel was performed in a heavy-duty PIDING engine with P inj = 140-220 bar, ϕ g = 0.47-0.71, and a constant NG energy fraction of 94%. Apparent heat release rate and emissions analyses identified interactions between the pilot fuel and NG, and qualitatively characterized the impact of NG stratification on combustion and emissions. Changes in the RIT resulted in six distinct PIDING combustion regimes, for all considered injection pressures and equivalence ratios: (i) RIT-insensitive premixed, (ii) stratified-premixed (early-cycle injection), (iii) NG jet impingement transition, (iv) stratified-premixed (late-cycle injection), (v) variable premixed fraction, and (vi) minimally-premixed. Parametric definitions for the bounds of each regime of combustion were valid for the wide range of P inj and ϕ g investigated, and are expected to be relevant for other PIDING engines, as previously identified regimes agree with those identified here. This conceptual framework encompasses and validates the findings of previous stratified PIDING investigations, including optimal ranges of operation that provide significantly increased efficiency and lower emissions of incomplete combustion products.

Experimental analysis on the influence of compression ratio, flow rate, injection pressure, and injection timing on the acetylene - diesel aspirated dual fuel engine.

The predicted scarcity, increasing cost of petroleum fuels, and environmental degradation are encouraging researchers to search for alternative fuels throughout the world. Hence, it is intended to utilize acetylene-based DF in the compression ignition (CI) engine with minor modifications. An engine of 5 Hp, four stroke, single-cylinder, water-cooled operated in dual-fuel (DF) mode (acetylene gas-diesel), aiming to reduce the emissions, was deployed to investigate its characteristics. In DF mode, gaseous fuel is injected through intake air manifold with 2, 4, and 6 lpm constantly. According to the research findings, the gas rate of 6 lpm provides the best results, having a superior BTE of 30.7%. Various compression ratios (16:1, 18:1, and 20:1) were used to determine the optimal compression ratio (CR) under a volume flow rate of 6 lpm with diesel. Fuel injector pressure (200, 220, and 240 bar) with injector intervals (19°, 23°, and 27°bTDC) were changed consecutive sequence while adjusting CR, and the best outcomes for improved CI fuel efficiency were determined. From the investigational analysis, the peak in-cylinder pressure and net HRR (heat release rate) are assessed for being better by the increment in CR in DF mode of operation with an acetylene gas of 6 lpm at all operating settings. At a 240 bar injection pressure, the BTE is recorded highest (35.1%), and smoke was decreased. An IT of 23obTDC, the CO and HC were found as to be minimum as 28 ppm and 0.04 ppm.

Effect of injection timing on knock combustion and pollutant emission of heavy-duty diesel engines at low temperatures.

The knock combustion and pollutant emission of heavy-duty diesel engines at low temperatures are still unclear, especially under different injection timings. Therefore, this study illustrates the above issues through CONVERGE simulation. The results show that with the start of injection (SOI) sweeps from -7°CA to -32°CA, a large amount of liquid-phase fuel adheres to the wall, and the wet-wall ratio of fuel at SOI = -32°CA is as high as nearly 30%. The fuel film evaporates slowly, coupled with the effect of low temperature on chemical reactions, the high-temperature ignition (HTI) is delayed seriously until the end of injection. The amount of premixed mixture formed during long ignition delay is significantly increased, but its uniformity is better and the concentration is more suitable for ignition. Once HTI is triggered, high-frequency and strong pressure oscillation occurs in the cylinder, and the maximum oscillation amplitude is as high as nearly 10 MPa, far exceeding the threshold of destructive knock combustion. Delayed fuel injection can effectively alleviate the above problems, such as the best when the SOI in this study is -17°CA. In addition, HC emissions are positively correlated with the amount of fuel film, but the trend of CO quantity with injection timing shows the opposite result. NOx emission increases as the injection timing advances, while soot is the opposite, because the mixture concentration is leaner at the earlier SOI and the expanded high-temperature region leads to an accelerated oxidation rate of soot.

Effects of intracytoplasmic sperm injection timing and fertilization methods on the development of bovine spindle transferred embryos.

Cytoplasmic replacement by spindle transfer (ST) technique can be applied to improve the developmental competence of poor qualitied or aged oocytes. In cattle, ST technology has not been well established for producing embryos and the calves successfully using intracytoplasmic sperm injection (ICSI) or in vitro fertilization (IVF). The objective of this study was to develop a novel procedure for producing bovine ST embryos, which could be fundamental to applying ST technology in other mammals. In the present study, the efficacies of performing ICSI before (ICSI-ST) or after (ST-ICSI) and IVF on the development of ST bovine embryos were investigated. Results indicated that the blastocyst rate of ST embryos produced by ICSI-ST (24.7%) was higher (P < 0.05) than that produced by ST-ICSI (5.9%). On the other hand, ST-IVF had the highest fertilization rate (97.3%), polyspermy rate (24.7%), and lowest blastocyst rate (22.7%) when compared to denuded oocytes (DO), zona cut oocytes (ZC), and cumulus-oocyte complexes (COCs)-IVF groups. Finally, the in vitro development rates of ICSI-ST (24.5%) and ST-IVF (25.2%) were not significantly different (P > 0.05). However, the pregnancy rate (46.7%) and birth rate (33.3%) of ST-IVF were higher (P < 0.05) than those of ICSI-ST (6.3% and 0%, respectively). The percentage of mitochondrial DNA (mtDNA) heteroplasmy derived from donor karyoplasts of the 5 claves was between 2% and 18%. Taken together, performing ICSI prior to ST can improve the embryonic development of ST bovine embryos. Moreover, using IVF, instead of ICSI, for ST oocyte fertilization dramatically increased the pregnancy rate and birth rate of ST calves, in which mtDNA heteroplasmy derived from donor karyoplasts exists.

Exploring the efficiency and pollutant emission of a dual fuel CI engine using biodiesel and producer gas: An optimization approach using response surface methodology.

The present study focuses on optimizing the engine operating parameters of a dual-fuel (DF) engine. Producer gas (PG) and Honge oil methyl ester (HOME) are used as primary fuel and pilot fuel respectively for the operation. An experimental design matrix of 20 different combinations was considered using Design of Experiments (DoE), based on the central composite design (CCD) of response surface methodology (RSM). The effects of these combinations were experimentally investigated to calculate the performance and emission characteristics of the engine. The objective of the work is to maximize the Brake thermal efficiency (BTE) and minimize the exhaust gas temperature (EGT), nitrogen oxide (NOx), hydrocarbon (HC), and carbon monoxide (CO) emissions. The RSM model is developed using the experimental data and further, the operating parameters were optimized using the desirability approach. The optimized combination of operating parameters was obtained at 61.10% engine load, compression ratio (CR) of 18, and injection timing (IT) of 23.30° before top dead center (BTDC). The optimum responses corresponding to these operating conditions were found as 14.23%, 354.29 °C, 52.18 ppm, 39.53 ppm, and 0.51% for BTE, EGT, NOx, HC, and CO respectively with an overall desirability of 0.962. The optimized responses were validated experimentally at optimum input conditions and found to be within acceptable error levels. Further, an economic analysis of the optimized DF system is also carried out.

Evaluation of Optimal Post-Injection Timing of Hypoxic Imaging with 18F-Fluoromisonidazole-PET/CT.

PURPOSE: Positron emission tomography (PET)/computed tomography (CT) using 18F-fluoromisonidazole (FMISO) has been used as an imaging tool for tumour hypoxia. However, it remains unclear whether they are useful when scanning is performed earlier, e.g. at 2-h post-injection with a high sensitivity PET scanner. This study aimed to investigate the relationship between quantitative values in 18F-fluoromisonidazole (18F-FMISO)-PET obtained at 2- and 4-h post-injection in patients with head and neck cancer. PROCEDURES: We enrolled 20 patients with untreated locally advanced head and neck cancer who underwent 18F-FMISO-PET/CT scan between August 2015 and March 2018 at our institute. Image acquisition was performed 2 h and 4 h after 18F-FMISO administration using a combined PET/CT scanner. The SUVmax, SUVmean, SUVpeak, tumour-to-blood ratio (TBR), tumour-to-muscle ratio (TMR), metabolic tumour volume (MTV), and total lesion hypoxia (TLH) were measured in the region of interest of the primary tumour. We evaluated the between-image Spearman's rank correlation coefficients and percentage differences in the quantitative values. The locations of the maximum uptake pixel were identified in both scans, and the distance between them was measured. RESULTS: The mean (SD) SUVmax at 2 h and 4 h was 2.2(0.7) and 2.4(0.8), respectively. The Spearman's rank correlation coefficients (ρ) and mean (SD) of the percentage differences of the measures were as follows: SUVmax (0.97; 7.0 [5.1]%), SUVmean (0.97; 5.2 [5.8]%), SUVpeak (0.94; 5.3 [4.7]%), TBR (0.96; 14.2 [9.8]%), TMR (0.96; 14.7 [8.4]%), MTV (0.98; 39.9 [41.3]%), and TLH (0.98; 40.1 [43.4]%). There were significant between-scan correlations in all quantitative values. The mean (SD) distance between the two maximum uptake pixels was 7.3 (5.3) mm. CONCLUSIONS: We observed a high correlation between the quantitative values at 2 h and 4 h. When using a combined high-quality PET/CT, the total examination time for FMISO-PET can be shortened by skipping the 4-h scan.

Soft computing-based modeling and emission control/reduction of a diesel engine fueled with carbon nanoparticle-dosed water/diesel emulsion fuel.

This study was set up to model and optimize the performance and emission characteristics of a diesel engine fueled with carbon nanoparticle-dosed water/ diesel emulsion fuel using a combination of soft computing techniques. Adaptive neuro-fuzzy inference system tuned by particle swarm algorithm was used for modeling the performance and emission parameters of the engine, while optimization of the engine operating parameters and the fuel composition was conducted via multiple-objective particle swarm algorithm. The model input variables were: injection timing (35-41° CA BTDC), engine load (0-100%), nanoparticle dosage (0-150 µM), and water content (0-3 wt%). The model output variables included: brake specific fuel consumption, brake thermal efficiency, as well as carbon monoxide, carbon dioxide, nitrogen oxides, and unburned hydrocarbons emission concentrations. The training and testing of the modeling system were performed on the basis of 60 data patterns obtained from the experimental trials. The effects of input variables on the performance and emission characteristics of the engine were thoroughly analyzed and comprehensively discussed as well. According to the experimental results, injection timing and engine load could significantly affect all the investigated performance and emission parameters. Water and nanoparticle addition to diesel could markedly affect some performance and emission parameters. The modeling system could predict the output parameters with an R2 > 0.93, MSE < 5.70 × 10-3, RMSE < 7.55 × 10-2, and MAPE < 3.86 × 10-2. The optimum conditions were: injection timing of 39° CA BTDC, engine load of 74%, nanoparticle dosage of 112 µM, and water content of 2.49 wt%. The carbon dioxide, carbon monoxide, nitrogen oxides, and unburned hydrocarbon emission concentrations were found to be 7.26 vol% , 0.46 vol% , 95.7  ppm, and 36.2 ppm, respectively, under the selected optimal operating conditions while the quantity of brake thermal efficiency was found at an acceptable level ( 34.0 %). In general, the applied soft computing combination appears to be a promising approach to model and optimize operating parameters and fuel composition of diesel engines.

Preoperative lumbar epidural steroid injections administered within 6 weeks of microdiscectomy are associated with increased rates of reoperation.

PURPOSE: Lumbar epidural steroid injections (LESIs) are widely utilized for back pain. However, as studies report adverse effects from these injections, defining a safe interval for their use preoperatively is necessary. We investigated the effects of preoperative LESI timing on the rates of recurrent microdiscectomy. METHODS: This study utilized the PearlDiver national insurance claims database. Microdiscectomy patients were stratified by the timing of their most recent LESI prior to surgery into bimonthly cohorts (0-2 months, 2-4 months, 4-6 months). This first cohort was further stratified into biweekly cohorts (0-2 weeks, 2-4 weeks, 4-6 weeks, 6-8 weeks). The 6-month reoperation rate was assessed and compared between each injection cohort and a control group of patients with no injections within 6 months before surgery. Univariate analyses of reoperation were conducted followed by multivariate analyses controlling for risk factors where appropriate. RESULTS: A total of 12,786 microdiscectomy patients were identified; 1090 (8.52%) received injections within 6 months before surgery. We observed a significant increase in the 6-month reoperation rates in patients who received injections within 6 weeks prior to surgery (odds ratio [OR] 1.900, 1.218-2.963; p = 0.005) compared to control. No other significant differences were observed. DISCUSSION: In this study, microdiscectomy performed within 6 weeks following LESIs was associated with a higher risk of reoperation, while microdiscectomy performed more than 6 weeks from the most recent LESI demonstrated no such association with increased risk. Further research into the interaction between LESIs and recurrent disk herniation is necessary.

Simulation data for similarity of spray combustion processes in marine low-speed diesel engines.

Scaled model experiments are very useful for reducing time, cost and energy consumption in marine diesel engine development. This data article is based on the research work which examines the potential of scaled model experiments for marine low-speed diesel engines. Two engines of 340 and 520 mm bore diameters are employed to conduct this numerical scaling work based on three diesel combustion scaling laws. Data on similarity of peak swirl ratio, heat transfer losses, liquid and vapor penetration length, ignition delay, in-cylinder peak temperature, peak carbon monoxide (CO), peak hydrocarbon (HC) and carbon dioxide (CO2) emissions for various fuel injection timing are provided. The data in this paper are valuable reference for researchers or engineers who attempt to conduct scaled model experiments in marine diesel engine development.

Preoperative corticosteroid joint injections within 2 weeks of shoulder arthroscopies increase postoperative infection risk.

BACKGROUND: There is currently no consensus regarding the safe timing interval between corticosteroid shoulder injections and future shoulder arthroscopies. Our study assessed the relationship between preoperative corticosteroid injection timing and shoulder arthroscopy infectious outcomes. METHODS: We used an insurance database to identify and sort all shoulder arthroscopy patients by corticosteroid shoulder injection history within 6 months before surgery. Patients who received injections were stratified by the timing of their most recent preoperative injection. The overall infection rate and rate of severe infections requiring treatment through intravenous antibiotics or surgical débridement in the 6-month postoperative period were compared using χ2 tests between the injection cohorts and a control group of patients defined as those with no injection history. RESULTS: We identified 50,478 shoulder arthroscopy patients, of whom 4115 received injections in the 6-month preoperative period. We found a significant increase in both the overall infection rate (P < .0001) and severe infection rate (P < .0001) in patients who received injections within 2 weeks before surgery (n = 79; 8.86% and 6.33%, respectively) compared with those who received no injections in the 6-month preoperative period (n = 46,363; 1.56% and 0.55%, respectively). No other significant differences were observed. CONCLUSIONS: Our results suggest that in patients who have received corticosteroid injections, shoulder arthroscopic procedures may be safely performed after at least 2 weeks has passed since the most recent injection to minimize the risk of postoperative infection. In addition, procedures performed within 2 weeks of an injection may increase the risk of postoperative infection.

Influence of injection timing and exhaust gas recirculation (EGR) rate on lemon peel oil-fuelled CI engine.

In the current phase of world economy, the utilization of the petroleum-based fossil fuels has drastically surpassed the supply. This scenario supplements to the fact that there is an ever increasing necessity for industrialization, specifically in the transportation sector. This requirement and supply of the petroleum and diesel fuels have an astounding impact over the market economy and related commodities. Low viscous and low cetane number biofuels are getting more attention for their usage in engine applications without any further processing. In the present work, lemon peel oil is being fuelled in diesel engine at different timing of injection and exhaust gas recirculation rates. Operation of lemon peel oil (LPO) at standard operating conditions results in increased brake thermal efficiency by consuming less fuel when compared with diesel fuel. The LPO biofuel properties such as boiling point and viscosity being lower leads to better evaporation capacity and thereby results in complete combustion. The advancement in injection timing of 25° bTDC and 27° bTDC resulted in the efficiency increment of 2.17% and 6.19% respectively. Furthermore, the smoke, carbon monoxide and hydrocarbon emissions are decreased in consequence on increased nitrogen oxide (NOx) emissions. Hence, in order to decrease the content of nitrogen oxide emissions in the exhaust, exhaust gas recirculation (EGR) has been implemented in the present work. For EGR rate of 10% and 20%, the NOx emissions is reduced by 43% and 46% respectively for 27° bTDC injection timing. Thus, the advancement of injection timing with optimum EGR is a viable option for the lemon peel oil biofuel in diesel engine with superior performance and emission output.

Engine parameter optimization of palm oil biodiesel as alternate fuel in CI engine.

Stringent emission regulations and depletion of crude oil are driving researchers toward alternative fuels. In this context, palm oil emerges as a good competitor as it is highly economical compared to other alternative fuels. The current research work centers around the impact of palm oil methyl ester on performance, combustion, and emission characteristics at varying injection timings and exhaust gas recirculation rates. In the first phase of this research work, various blends of palm oil methyl ester with diesel with volume concentrations of 10, 20, and 30% were prepared and tested at different load conditions. Injection timing was then varied for the optimized blend. In the second phase, the impact of exhaust gas blending with fresh charge was studied at optimized injection timing. The test outcomes revealed that 20% mix of palm oil at 27° bTDC with exhaust gas blending of 20% generated higher brake thermal efficiency, higher peak pressure, and less hydrocarbon and nitrogen oxide emissions compared to diesel at standard injection timing of 23° bTDC and no blending of exhaust gases with fresh charge. However, progression of injection timing with 20% exhaust gas mixing indicated a slight penalty in smoke discharges. Brake thermal efficiency at advanced injection timing with 20% mix of exhaust gases reduced by 7.7% for diesel and increased by 6.5% for 20% blend of palm oil when compared to standard injection timing of diesel and no blending of exhaust gases. Significant diminishments in oxides of nitrogen (lessened by 6.6%) and hydrocarbons (decreased by 30.43%) have been noted for 20% mix of biodiesel at advanced injection timing with 20% exhaust gas mix contrasted to diesel at standard conditions. Therefore, the present examination prescribes 20% merging of exhaust gases for 20% blend of palm oil with advancement of injection timing for diesel engine applications.