Noora S. Ekab¹, Ahmed Q. Salam², Ali O. Abd³, Miqdam T. Chaichan^4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2847-2861, 2023, DOI:10.32604/fdmp.2023.028874

Abstract To improve the performances of diesel engines and to reduce the pollutants they emit, aluminum oxide nanoparticles in varying quantities (50, 100, 150 ppm) have been added to conventional diesel fuel. The results of such experimental tests have revealed that the addition of nano-Al₂O₃ particles to the diesel fuel reduces its consumption by 0.488%, 1.02%, and 1.377%, respectively and increases the brake thermal efficiency by 1.4%, 2.6%, and 3.8%, respectively. The concentrations of undesired gases decrease accordingly by 1.5%, 1.7%, and 2.8% for HC and by 5.88%, 11.7%, and 17.6%, respectively, for CO. For the same percentages of nanoparticles, NOx… More >

Yaofei Zhang¹, Guoxiang Li¹, Shuzhan Bai¹, Ke Sun^1,*, Guihua Wang^1,*, Yujie Jia², Zhengxian Fang²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.11, pp. 2933-2951, 2023, DOI:10.32604/fdmp.2023.028804

Abstract Multiphase simulations based on the VOF (Volume of Fluid) approach, used in synergy with the cavitation Schnerr-Sauer method and the K-Epsilon turbulence model, have been conducted to study the behavior of an injector nozzle as a function of relevant structural parameters (such as the spray hole diameter and length). The related performances have been optimized in the framework of orthogonal experimental design and range analysis methods. As made evident by the results, as the spray hole diameter increases from 0.10 to 0.20 mm, the outlet mass flow rate grows by 243.23%. A small diameter of the spray hole, however, has… More >

Vijayakumar Thulasi, R. Thundil Karuppa Raj^*

Frontiers in Heat and Mass Transfer, Vol.10, pp. 1-9, 2018, DOI:10.5098/hmt.10.33

Abstract Diethyl ether is one of the potential alternative fuels for the high speed compression ignition engines that can replace the existing neat diesel fuel. It is well known that the combustion characteristic of a compression ignition engine is highly influenced by the fuel spray structure formed during the injection process. In this paper the spray structure formation for the diethyl ether fuel is studied numerically, using the discrete phase model and it is compared with the neat diesel fuel. The spray is investigated in a constant volume chamber maintained at 30 bar pressure. The fuel is injected into the chamber… More >

Xincan Song^1,3,4, Lin Wang^1,3,4,*, Cheng Yu^1,2, Jiaxin Chen^1,3,4, Linjie Ma^1,3,4

Energy Engineering, Vol.120, No.8, pp. 1837-1852, 2023, DOI:10.32604/ee.2023.027637

Abstract The coupled formation of wax crystals and hydrates is a critical issue for the safety of deep-sea oil and gas exploration and subsea transport pipeline flow. Therefore, this paper conducts an experimental study on the characteristics of methane hydrate formation in a water-in-oil (W/O) system with different wax crystal contents and explores the influence of different initial experimental pressures on the induction period and maximum rate of hydrate formation. The wavelet function was introduced to process the reaction rate and calculate the maximum speed of hydrate formation. Notably, the higher the pressure, the smaller the maximum rate of hydrate formation.… More >

Hawraa S. Mohammed^*, Mahmoud A. Mashkour

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2329-2343, 2023, DOI:10.32604/fdmp.2023.026890

Abstract This study considers the effect of Eichhornia Crassipes Biodiesel (ECB) blends on the performances, combustion, and emission characteristics of a direct injection compression ignition engine operated in a dual-fuel mode (DFM) and equipped with an Exhaust gas recirculation technique (EGR). In particular, a single-cylinder, four-stroke, water-cooled diesel engine was utilized and four modes of fuel operation were considered: mode I, the engine operated with an ordinary diesel fuel; mode II, the engine operated with the addition of 2.4 L/min of liquefied petroleum gas (LPG) and 20% EGR; mode III, 20% ECB with 2.4 L/min LPG and 20% EGR; mode IV,… More >

Jianfeng Pan^*, Jinpeng Hua, Jiaqi Yao, Abiodun Oluwaleke Ojo

Energy Engineering, Vol.120, No.7, pp. 1541-1562, 2023, DOI:10.32604/ee.2023.027873

Abstract The group-hole nozzle concept is proposed to meet the requirement of nozzle hole minimization and reduce the negative impact of poor spatial spray distributions. However, there are limited researches on the effects of intake conditions and nozzle geometry on spray characteristics of the group-hole nozzle. Therefore, in this study, an accurate spray model coupled with the internal cavitating flow was established and computational fluid dynamics (CFD) simulations were done to study the effects of intake conditions and nozzle geometry on spray characteristics of the group-hole nozzle. Experimental data obtained using high-speed digital camera on the high-pressure common rail injection system… More >

Hussein Al-Gburi^*, Doaa Fadhil Kareem, Malik N. Hawas

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-6, 2022, DOI:10.5098/hmt.18.28

Abstract In this article, an investigational analysis has been conducted to explore the effect of biodiesel fuel blends on characteristics of engine and releases (CO2, CO, HCl, and NOx) of single-cylinder, four strokes at the variable biodiesel concentration. The releases of gases and the engine's characteristics were measured at six blending biofuels and six-speed conditions and constant load. The blending proportions of biodiesel with diesel fuel-based by volume were at 0% pure diesel, 5%, 10%, 15%, 20%, and 25%. This investigation aims to assess the biodiesel fuel mixture's impact on the CI engine performance in terms of its Bsfc, Ƞbth, and… More >

Chao Zhu¹, Zhuopei Liu², Hao Chen^2,3, Yangyang Li^2,3,*

Energy Engineering, Vol.120, No.5, pp. 1081-1105, 2023, DOI:10.32604/ee.2023.026000

Abstract Experiments were conducted on a diesel-methanol dual-fuel (DMDF) engine modified by a six-cylinder, turbo-charged, inter-cooled diesel engine. According to the number of diesel injection, the experiments are divided to two parts: the single injection mode and double injection mode. The results show that, at the double injection mode, the maximum of pressure rise rate is small and the engine runs smoothly, however, knock still occurs when the co-combustion ratio (CCR) is big enough. Under knock status, the power density of the block vibration concentrating at some special frequencies rises dramatically, and the special frequency of single injection mode (about 4.1… More >

Da Li, Guodong Zhang, Ke Sun^*, Shuzhan Bai, Guoxiang Li^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1479-1493, 2023, DOI:10.32604/fdmp.2023.022634

Abstract A dedicated heat exchanger model is introduced for the optimization of heavy-duty diesel engines. The model is a prerequisite for the execution of CFD simulations, which are used to improve waste heat recovery in these systems. Several optimization methods coupled with different types of working fluids are compared in terms of exergy efficiency and heat exchanger complicity. The three considered optimization methods all lead to significant improvements in the R245fa and R1233zd systems with a comparatively low evaporation temperature. The optimal R245fa system has the highest efficiency increase (77.49%). The cyclopentane system displays the highest effi- ciency among the optimized… More >

Tobias Drieschner^1,2,*, Andreas Kandelbauer¹, Bernd Hitzmann², Karsten Rebner¹

Journal of Renewable Materials, Vol.11, No.4, pp. 1643-1660, 2023, DOI:10.32604/jrm.2023.024429

Abstract For optimization of production processes and product quality, often knowledge of the factors influencing the process outcome is compulsory. Thus, process analytical technology (PAT) that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and quality. The present study aims at characterizing a well-known industrial process, the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters (FAME) for usage as biodiesel in a continuous micro reactor set-up. To this end, a… More >