Combustion characteristics of a diesel engine running with Mandarin essential oil -diesel mixtures and propanol additive under different exhaust gas recirculation: Experimental investigation and numerical simulation

Essential oils are promising sources for producing alternative fuel, owing to their sustainability and obtainability. Thus, this article aimed to investigate the impacts of introducing mandarin-essential oil with diesel fuel on the engine performance operated under numerous loads and a fixed speed of 1500 rpm. There are two mixing ratios of 10% and 20% mandarin essential oil and 80%, and 90% diesel fuel, which are signified as MO10 and MO20, respectively. Then, the Diesel-RK model is used to predict the influence of adding propanol (10% by volume) to (90%) mandarin-essential oil with applying EGR of 1%, 3% and 5% approach. The Egyptian-mandarin-essential oil is characterized using gas-chromatography–mass-spectrometry analysis, and its physical properties are measured corresponding to ASTM standard. The experimental findings demonstrate that the cylinder pressure and HRR are decreased by 3% and 2.5%, respectively, with the supplement of mandarin-essential-oil with diesel fuel. The CO, UHC, and smoke opacity are lowered by (17%, 30%), (20%, 40%), and (27%, 44%) for MO10 and MO20 combinations, compared with the base fuel, while the NOx intensity is inflated by 25% and 45% respectively. Specific fuel consumption is decreased by 5% and 22% for MO10 and MO20 blends, respectively. The validation indicates a decent acceptance among the experimental and simulation data. The simulation findings demonstrate that the EGR approach effectively lowers the NOx level with the minimum effect on the soot level

Investigation of waste cooking and castor biodiesel blends effects on diesel engine performance, emissions, and combustion characteristics

Waste cooking (WCO) and castor oils are used as methyl ester feedstocks. By esterification and transesterification of castor and WCO, biodiesels were created and combined with diesel in proportions of 10 % and 20 %. Diesel engine emissions, performance, and combustion were computed at 3000 rpm rated speed and load variation. Highest increases in specific fuel consumption of 2, 3.5, 5.5, 6, and 8.5 % were seen in the cases of waste cooking (10 %), castor biodiesel (10 %), blending (10 %), waste cooking (20 %), and castor (20 %) when diesel fuel was utilized at full load. Thermal efficiencies were decreased by 2.5, 4, 5, 6, and 9.5 % in proportion. Compared to diesel oil, WB10, CB10, WB10+CB10, WB20, and CB20 displayed the biggest reductions in CO emissions of 0.5, 1.5, 2.5, 3, and 3.5 %, respectively; in contrast, NOx concentrations climbed to 1.5, 2.5, 3.5, 5, and 6.5 %, respectively. Largest reductions in hydrocarbon emissions were shown for biodiesel blends as 6, 7, 10, 12, and 14 %, respectively. Largest declines in smoke at peak load were seen for WB10, CB10, WB10+CB10, WB20, and CB20, with respectively values of 6, 8, 10.5, and 11 %. Decrements in maximum cylinder pressure were 1.5, 2, 2.3, 3.5, and 4.5 % at peak load related to diesel. There were 1.5, 2.5, 3, 4.5, and 5 % drops in peak HRR, respectively. Improvement of emissions, performance, and combustion characteristics associated with diesel engine fueled by mixtures of WCO, and castor methyl ester is achieved through the hybridization of feedstocks with different properties as 10 % castor and 10 % WCO biodiesels

Natural Fiber-Reinforced Thermoplastic ENR/PVC Composites as Potential Membrane Technology in Industrial Wastewater Treatment: A Review

Membrane separation processes are prevalent in industrial wastewater treatment because they are more effective than conventional methods at addressing global water issues. Consequently, the ideal membranes with high mechanical strength, thermal characteristics, flux, permeability, porosity, and solute removal capacity must be prepared to aid in the separation process for wastewater treatment. Rubber-based membranes have shown the potential for high mechanical properties in water separation processes to date. In addition, the excellent sustainable practice of natural fibers has attracted great attention from industrial players and researchers for the exploitation of polymer composite membranes to improve the balance between the environment and social and economic concerns. The incorporation of natural fiber in thermoplastic elastomer (TPE) as filler and pore former agent enhances the mechanical properties, and high separation efficiency characteristics of membrane composites are discussed. Furthermore, recent advancements in the fabrication technique of porous membranes affected the membrane’s structure, and the performance of wastewater treatment applications is reviewed

Improving the thermal-hydraulic performance of parabolic solar collectors using absorber tubes equipped with perforated twisted tape containing nanofluid

The thermal and hydraulic efficiency of a parabolic trough solar collector is investigated in this study. The collector absorber tube is equipped with twisted tape with circular holes containing water-copper oxide nanofluid with three nanoparticles volume fractions of 1%, 2% and 4%. In three modes (d/W = 0.5, 0.7, 0.9), circular holes are constructed for the ratio of the circle's diameter to the twisted tape's breadth. All turbulent flow simulations were done using the SIMPLEC algorithm, FVM and RNG k-ε model in three Reynolds numbers as 10,000, 20,000 and 30,000. Studies have shown inserting twisted tape with a circular hole increases the pressure drop and the heat transfer rate compared to a pipe without twisted tape. The highest coefficient of thermal performance occurs in Reylond number of 10,000 and a nanoparticles volume fraction of 4%. The findings indicate that using nanoparticles improves the solar collector's energy and exergy efficiency. As a result, the best collector performance was obtained when using nanofluids with an nanoparticles volume fraction of 4%.The Deanship of Scientific Research at King Khalid University, Abha, Saudi Arabia.http://www.elsevier.com/locate/seta2024-04-11hj2023Mechanical and Aeronautical Engineerin

Numerical study and optimization of thermal efficiency for a pin fin heatsink with nanofluid flow by modifying heatsink geometry

This paper presents a numerical study on the thermal efficiency of a pin fin heatsink (HEK). The working fluid used is an alumina/water nanofluid, which enters the HEK in a laminar flow regime and exits from its surroundings. This study involves varying the distance between circular pin fins, their height, and their diameter. By altering these parameters, we determine the values of thermal resistance (THR) and temperature uniformity (Teta) on the HEK, along with the heat transfer coefficient (HTC). We further optimize the obtained results using artificial intelligence techniques to minimize the THR of the HEK, maximize the HTC, and achieve the best Teta on the HEK. This numerical investigation employs a two-phase approach to model nanofluid flow within the HEK. The optimization process yields predictions with an accuracy of less than 4%. The findings reveal that increasing the height of the pin fins reduces the HTC and the heat capacity of the HEK, while simultaneously improving the Teta on the HEK. Expanding the distance between pin fins enhances the HTC, decreases the THR of the HEK, and further improves the Teta on the HEK. Similarly, augmenting the diameter of the pin fins amplifies the HTC, reduces the THR, and enhances the Teta on the HEK

A case study on analyzing the performance of microplate heat exchanger using nanofluids at different flow rates and temperatures

A microplate heat exchanger is one of the most compact types of heat exchanger used for cooling systems, and not much research was carried out to study the performance of this type of heat exchanger with hybrid nanofluids. In this regard, the performance analysis of the microplate heat exchanger is carried out by estimating the convective heat transfer coefficient in terms of Nusselt number using a hybrid nanofluid. In current research work, Microplate heat exchangers tested using TiO2/ethylene glycol, ZnO/ethylene glycol nanofluids, and a hybrid nanofluid with varied nanoparticle volume fractions. Based on the results, it was found that the thermal conductivity of hybrid nanofluids and the overall heat transfer coefficient by applying hybrid nanofluids show better enhancement than nanofluids. The maximum thermal conductivity ratio between the hybrid nanofluid and the base fluid is 2.10. The maximum Nusselt number of 35.8 was observed for hybrid (TiO2–ZnO/ethylene glycol) at 50 °C and a volume fraction of 4%

An extensive review of performance enhancement techniques for pyramid solar still for solar thermal applications

Due to the rapid increase on world population, the demand for potable water is also getting increased. The solar distillation process is one among the prominent options, for those facing shortage of water in rural areas. Many researchers have put tremendous effort in designing a solar still with better efficiency in the last decade. Current review article demonstrates the recent studies carried out on pyramid solar still to enhance the distillate output. It includes the use of use of fins, phase change materials, coatings, flat plate collector, and evacuated tube collector to enhance the distillate output of pyramid solar still. Comparison of various parameters for different solar distillation system and various aspects in improving the performance of a pyramid solar still also discussed in tabular form. At last, Scope of further research & recommendations for Pyramid solar still is added for help to researchers.This publication was supported by Qatar University Internal Grant No. QPH3P-CAM-2021-452

Multiple machine learning models for prediction of CO2 solubility in potassium and sodium based amino acid salt solutions

In this work, we developed artificial intelligence-based models for prediction and correlation of CO2 solubility in amino acid solutions for the purpose of CO2 capture. The models were used to correlate the process parameters to the CO2 loading in the solvent. Indeed, CO2 loading/-solubility in the solvent was considered as the sole model’s output. The studied solvent in this work were potassium and sodium-based amino acid salt solutions. For the predictions, we tried three potential models, including Multi-layer Perceptron (MLP), Decision Tree (DT), and AdaBoostDT. In order to discover the ideal hyperparameters for each model, we ran the method multiple times to find out the best model. R2 scores for all three models exceeded 0.9 after optimization confirming the great prediction capabilities for all models. AdaBoost-DT indicated the highest R2 Score of 0.998. With an R2 of 0.98, Decision Tree was the second most accurate one, followed by MLP with an R2 of 0.9