Flow and heat transport phenomenon for dynamics of Jeffrey nanofluid past stretchable sheet subject to Lorentz force and dissipation effects

Survey of literature unveils that nanofluids are more efficient for heat transport in comparison to the traditional fluids. However, the enlightenment of developed techniques for the augmentation of heat transport in nanomaterials has considerable gaps and, consequently, an extensive investigation for aforementioned models is vital. The ongoing investigation aims to study the 2-D, incompressible Jeffrey nanofluid heat transference flow due to a stretchable surface. Furthermore, the effect of dispersion of graphene nanoparticles in base liquid ethylene glycol (EG) on the performance of flow and heat transport using the Tawari-Das model in the existence of Ohmic heating (electroconductive heating) and viscous heat dissipation is contemplated. The boundary-layer PDEs are reconstituted as ODEs employing appropriate similarity transformation. Keller-Box Method (KBM) is utilized to determine the numerical findings of the problem. Graphene conducts heat greater in rate than all of the other materials and it is a good conductor of electrical energy. Graphene/EG nanofluid is employed to look out the parametric aspects of heat transport flow, drag coefficient, and heat transference rate phenomena with the aid of graphs and tables. The numerical outcomes indicate that concentration and magnetic field abate the shear stresses for the nanofluid. An increase of Graphene nanoparticle volume fraction parameter can boost the heat transport rate. The effect of Prandtl Number is to slow down the rate of heat transport as well as decelerate the temperature. Additionally, the rate of heat transportation augments on a surface under Deborah's number. Results indicate that the temperature of the graphene-EG nanofluid is greater than the convectional fluid hence graphene-EG nanofluid gets more important in the cooling process, biosensors and drug delivery than conventional fluids.

Dynamics of dust particles in a conducting water-based kerosene nanomaterials: a computational approach

The magnetohydrodynamic nanofluid flow comprised of dust particles is carried out in the current investigation. The role of dust nanoparticles on the flow characteristics is vital. The radiative heat phenomena for the interaction of Cu nanoparticle are deliberated in this discussion. However, both water and oil (kerosene) are treated as conventional fluids. Regarding the current applications on nanofluid in industries for the production of several materials, it is important to use the nanoparticles as a coolant. In recent applications, for the CPU cooler Cu-nanoparticle is used because of its high thermal conductivity and as a good conductor of heat. The governing flow characteristics involved with nonlinear properties of partial differential equations are transformed into ordinary differential equations using suitable similarity variables. Further, numerical treatment is imposed using the in-build Matlab code bvp5c. The imitation is carried out for the various profiles using physical parameters and presented graphically. The numerical values for the rate coefficients are presented via tables and deliberated briefly.

KARAKTERISTIK MEKANIS CAMPURAN LASTON ATAS DENGAN PENAMBAHAN LIMBAH BUBUTAN BAJA

The flexible pavement is burdened by a high volume of traffic vehicles leads to damage to the road. The innovation of the use of steel waste can also be one of the efforts to minimize the damage of the plight because steel waste is a good conductor and can help manage the surrounding waste to reduce the negative impact of waste on the community. Through this research, the mechanical characteristics of waste steel as added material will be tested for the type of asphalt concrete wearing course. Thus it will be known benefits of use of steel waste against asphalt mixture. . By using the waste of steel with the size of ±. 0,5 cm and with a variation of 0,25%, 0,5%, 0,75%, and 1% and the optimum asphalt rate obtained from previous research at 5,7%. Once obtained characteristic data Marshall mixture, the research continue to determine the optimum material level with a narrow range method and performed mechanistic analysis of empirical using KENPAVE. , Then the results of the test can be seen in the characteristic Marshall, which is where these values are based on the general specifications of the Directorate General of Bina Marga Edition 2018.ABSTRAKPerkerasan lentur yang terbebani oleh volume lalu lintas yang tinggi dan menyebabkan terjadinya kerusakan pada jalan. Salah satu inovasi yang dapat digunakan untuk meminimalisir kerusakan lapis perkerasan dengan menggunakan limbah bubutan baja sebagai bahan tambah. Limbah bubutan baja merupakan konduktor yang baik, penggunaan bubutan baja ini juga dapat menjadi salah satu upaya untuk mengelola limbah yang ada di sekitar agar mengurangi dampak negatif limbah terhadap masyarakat. Melalui penelitian ini, karakteristik mekanis limbah bubutan baja sebagai bahan tambah akan diuji untuk jenis campuran asphalt concrete wearing course (AC – WC). dengan demikian akan diketahui manfaat penggunaan limbah bubutan baja terhadap campuran aspal. Dengan menggunakan limbah bubutan baja yang sudah dipotong hingga ukuran ±.0,5 cm dan dengan kadar variasi sebesar 0,25%, 0,5%, 0,75%, dan 1% serta kadar aspal optimum yang didapat dari penelitian sebelumnya, yaitu sebesar 5,7%. Setelah didapatkan data karakteristik Marshall campuran, penelitian dilanjutkan untuk menentukan kadar bahan optimum dengan metode narrow range dan dilakukan analisis mekanistik empiris menggunakan KENPAVE. Kemudian hasil pengujian tersebut dapat dilihat pada karakteristik Marshall , yang dimana nilai-nilai tersebut berdasarkan Spesifikasi Umum Direktorat Jendral Bina Marga Edisi 2018.

Influence of temperature on the displacement threshold energy in graphene

The atomic structure of nanomaterials is often studied using transmission electron microscopy. In addition to image formation, the energetic electrons impinging on the sample may also cause damage. In a good conductor such as graphene, the damage is limited to the knock-on process caused by elastic electron-nucleus scattering. This process is determined by the kinetic energy an atom needs to be sputtered, i.e. its displacement threshold energy Ed. This is typically assumed to have a fixed value for all electron impacts on equivalent atoms within a crystal. Here we show using density functional tight-binding simulations that the displacement threshold energy is affected by thermal perturbations of atoms from their equilibrium positions. This effect can be accounted for in the estimation of the displacement cross section by replacing the constant threshold energy value with a distribution. Our refined model better describes previous precision measurements of graphene knock-on damage, and should be considered also for other low-dimensional materials.

Thermal-siphon phenomenon and thermal/electric conduction in complex networks

In past decades, a lot of studies have been carried out on complex networks and heat conduction in regular lattices. However, very little attention has been paid to the heat conduction in complex networks. In this work, we study (both thermal and electric) energy transport in physical networks rewired from 2D regular lattices. It is found that the network can be transferred from a good conductor to a poor conductor, depending on the rewired network structure and coupling scheme. Two interesting phenomena were discovered: (i) the thermal-siphon effect—namely the heat flux can go from a low-temperature node to a higher-temperature node and (ii) there exits an optimal network structure that displays small thermal conductance and large electrical conductance. These discoveries reveal that network-structured materials have great potential in applications in thermal-energy management and thermal-electric-energy conversion.

PECULIARITIES OF OCCUPATIONAL PREVALENCE IN AIRCRAFT MANUFACTURING ENTERPRISES

At aircraft manufacturing enterprises, tens of thousands of employees work, whose labor conditions in most cases do not meet sanitary and hygienic requirements. Material and methods. The work assesses the risk factors of the production environment of aircraft assemblers using instrumental research methods, there was performed a physiological assessment of severity and exhaustion levels to determine the main areas of prevention. Results. The noise and vibration were determined as prioritized harmful impact (physical) factor for workers. Vibration is perceived by all tissues of the body, but mostly by the nervous and bone system. The bone system that serves as a good conductor and resonator of vibration. The nerve endings and, above all, the receptors of the skin of the distal parts of the hands are the most sensitive to the effects of vibration. The vestibular apparatus actively reacts to vibrational stimulation. In addition, vibrations of high frequencies can have an effect on the hearing aid that is close to the effect of noise. Discussion. The results of studies indicate a high risk of the formation of occupational pathology as a result of the complex impact of physical factors and the severity of the work process. Conclusion. Studies have shown the need to introduce rational work regimes and a system of treatment and prevention activities.

Electrical Properties of Steel Fibre Reinforced Alkali-Activated Slag Composite

Alkali-activated slag is an alternative binder to the ordinary Portland cement. In order to improve its tensile properties steel fibres as dispersed reinforcement can be used. Since steel is very good conductor it changes the electrical properties of alkali-activated slag composite that can have a potential to be used as self-sensing material then. In this study up to 20% of steel fibres by mass of the slag was added to alkali-activated slag mortar and the mechanical properties, electrical resistance, capacitance and microstructure of the composites were investigated. The results showed that the best improvement of both the mechanical and electrical properties can be observed for the composite with 15% of steel fibres.

A Theoretical Investigation on Structural and Electronic Properties of MgTl

Intermetallic compounds are innovative materials and are far superior to conventional metals and alloys. These intermetallic compounds have a great potential in industrial and technological fields because most of the intermetallic compounds are stronger as well asstiffer at elevated temperature and provide far better corrosion resistance than conventional metals and alloys.Over the past few years the scientific interest in the study of these intermetallic compounds emanates greatly because of their high-tech applications. Our motivation of the present studyMgTl mainly consernedon the physical data generation in context with its possible vast applications .We used a theoretical approach within the local density approximation method to study the structural and electronic properties of MgTl by calculating total energy. As far as our calculations are concerned, the band structure shows the overlapping of conduction and valence band thus itis clear that MgTl in its pure form is a good conductor of heat and electricity and falls in the category of metals. We have also calculated lattice parameters, bulkmodules, first order derivative electronic and lattice heat coefficient and Debye temperature.