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1.
Sci Rep ; 14(1): 19528, 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39174583

ABSTRACT

The use of nano additives to improve the cold properties of biodiesel is encouraged by its drawbacks and incompatibility in cold climate. Waste cooking oil (WCO) was transesterified to create biodiesel. A 20% by volume was used for combination of diesel and methyl ester. Current study aims to evaluate diesel engine emissions and performance. TiO2, alumina, and hybrid TiO2 + Al2O3 nanoparticles are added to WCO biodiesel mixture at 25 mg/liter. When B20 combined with nano materials such as TiO2, Al2O3, and hybrid nano, the highest declines in brake specific fuel consumption were 4, 6, and 11%, respectively. As compared to biodiesel blend, the largest gains in thermal efficiency were 4.5, 6.5, and 12.5%, respectively, at maximum engine output power. Introduction of TiO2, Al2O3, and hybrid nano particles to B20 at 100% load resulted in the highest decreases in HC concentrations up to 7, 13, and 20%, and the biggest reductions in CO emissions, up to 6, 12, and 16%. Largest increases in NOx concentrations at full load were about 7, 15, and 23% for B20 + 25TiO2, B20 + 25 Al2O3, and B20 + 25TiO2 + 25 Al2O3, respectively. Up to 8, 15, and 21% less smoke was released, correspondingly, which were the largest reductions. Recommended dosage of 25 ppm alumina and 25 ppm TiO2 achieved noticeable improvements in diesel engine performance, combustion and emissions about B20.

2.
Heliyon ; 9(7): e17660, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37449142

ABSTRACT

The present study is established on a simulation using CFD analysis in COMSOL. Blood acted as the base fluid with this simulation. The taken flow is been modeled as incompressible, unsteady, laminar and Newtonian fluid, which is appropriate at high rates of shear. The characteristic of flow of blood is been studied in order to determine pressure, velocity and temperature impact caused by an abdominal aortic aneurysm (AAA). This work employs nanoparticles of the Iron Oxide (Fe3O4) type. The CFD technique is utilized to evaluate the equations of mass, momentum, and energy. The COMSOL software is utilized to generate a normal element sized mesh. The findings of this study demonstrate that velocity alters through aneurysmal part of the aorta, that velocity is higher in a diseased segment, and that velocity increases before and after the aneurysmal region. For the heat transfer feature, the reference temperature and general inward heat flux is taken as 293.15K and 800W/m2. The nanoparticles altered blood's physical properties, including conductivity, dynamic viscosity, specific heat, and density. The inclusion of Iron Oxide (Fe3O4) nanoparticles managed to prevent overheating because taken nanoparticles have significant thermal conductivity. These findings will be extremely beneficial in the treatment of abdominal aortic aneurysm.

3.
Sci Rep ; 13(1): 10830, 2023 Jul 04.
Article in English | MEDLINE | ID: mdl-37402947

ABSTRACT

An exploration is made to investigate numerically and theoretically the time dependent flow of blood along with heat transfer through abnormal artery having trapezoidal shaped plaque. The flow is taken to be Newtonian, laminar, unsteady and incompressible. A suitable geometrical model is constructed to simulate the trapezoidal stenosis affected artery. The governed 2-dimensional momentum and heat transfer equations are conventionalized by assuming mild trapezoidal stenosis. The renovate partial differential equations are further converted into ordinary differential equations by assist of transformations. The novelty of the work is to consider unsteady blood flow through trapezoidal shape stenosed artery. A technique of finite difference is used to discretize the updated dimensionless model numerically. Comprehensive graphical outcomes for a flow of blood are obtained. The effect of trapezoidal plaque on blood velocity, pressure and temperature are shown by surface graph inside the artery and also shown with the help of line graph.

4.
Sci Rep ; 13(1): 1953, 2023 Feb 02.
Article in English | MEDLINE | ID: mdl-36732568

ABSTRACT

Nanofluids with their augmented thermal characteristics exhibit numerous implementations in engineering and industrial fields such as heat exchangers, microelectronics, chiller, pharmaceutical procedures, etc. Due to such properties of nanofluids, a mathematical model of non-Newtonian Casson nanofluid is analyzed in this current study to explore the steady flow mechanism with the contribution of water-based Aluminum oxide nanoparticles. A stretchable surface incorporating variable thickness is considered to be the source of the concerning fluid flow in two-dimension. An exponential viscosity of the nanofluid is proposed to observe the fluid flow phenomenon. Different models of viscosity including Brinkman and Einstein are also incorporated in the flow analysis and compared with the present exponential model. The physical flow problem is organized in the boundary layer equations which are further tackled by the execution of the relevant similarity transformations and appear in the form of ordinary nonlinear differential equations. The different three models of nanofluid viscosity exhibit strong graphical and tabulated relations with each other relative to the various aspects of the flow problem. In all concerned models of the viscosity, the deteriorating nature of the velocity field corresponding to the Casson fluid and surface thickness parameters is observed.

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