Behavior Of Physical Parameters Research Articles

Flow dynamics and convective transport analysis of two-layered dissipative Casson hybrid nanofluid flow in a vertical channel

This paper undertakes a thorough study to examine heat and mass transfer of two-layer hybrid nanofluid flow in a vertical channel. Casson fluid model is used to investigate the non-Newtonian nature of blood flow (base fluid) in this study. The problem is formulated which includes laminar, incompressible flow with additional viscous dissipation effects. Titanium dioxide and Graphene nanoparticles are employed in this study for the hybrid notion. At the interface, it is considered that the velocity and temperature remain continuous. A group of non-dimensional transformations are used to non-dimensionalized the set of ordinary differential equations and those non-linear differential equations are then solved using an analytical method known as homotopy analysis method (HAM). The behavior of physical parameters on velocity and temperature are presented graphically. Variation of Nusselt number against emerging parameters are tabulated to provide numerical data for validation. The findings of present study can provide insight into the behavior of blood flow in diseased conditions atherosclerosis, thrombosis, and other cardiovascular diseases. This study can also help in designing more effective drug delivery systems for targeted therapies.

Prediction of the Performance of Photovoltaic Modules from the Behavior of Physical Parameters According to Irradiance and Temperature

Prediction of the Performance of Photovoltaic Modules from the Behavior of Physical Parameters According to Irradiance and Temperature

Modeling of traversable wormholes in exponential f(R, T) gravity

In the present communication, we have studied the existence of wormholes described by a logarithmic shape function, in the exponential f(R, T) gravity given by f(R, T) = R + 2ξeζt where ξ and ζ are arbitrary constants, under three different sets of physical constraints. The logarithmic shape function is well behaved, satisfying all the necessary constraints for traversable and asymptotically flat wormholes. The obtained wormhole solutions are analyzed from the energy conditions for different values of involved physical constants. It has been observed that our proposed shape function for the exponential form of f(R, T) gravity represents the existence of exotic matter with a standard violation of the NEC. Moreover, for the trace T = 0, for the general relativity case with R being replaced by R + 2, the wormhole geometry has been analyzed to prove the existence of exotic matter. Further, the behaviour of physical parameters, such as the energy density ρ, the trace T, and anisotropy parameter Δ, describing the geometry of the universe has been presented with the help of graphs.

Anisotropic stellar structures in curvature-matter coupling gravity

In this paper, we investigate the existence of anisotropic compact stellar structures in the framework of f(G,T) gravity. We assume static spherically symmetric spacetime and utilize the embedding class-I approach to evaluate the unknown metric functions corresponding to a particular f(G,T) model. We determine the unknown constants by matching the interior and exterior geometries. The viability of the model is checked for different compact stars through energy bounds, compactness, gravitational redshift, Heintzmann condition for adiabatic index and Herrera stability condition but the graphical analysis is given only for SAX J1808.4-3658 compact star candidate. The behavior of physical parameters indicates viable and stable structure of the stellar model.

Time-dependent 3D flow of viscoelastic nanofluid over an unsteady stretching surface

This article addresses the unsteady three-dimensional flow of second grade nanofluid due to thermophoresis and Brownian motion effects. The flow is generated due to unsteady stretching in two lateral directions. The zero nanoparticles mass flux boundary conditions are imposed to find the desired solutions. By introducing the dimensionless variables the governing system of partial differential equations are transformed into the system of ordinary differential equations. Series solutions of the transformed ordinary differential equations are computed. Solutions are carried out for dimensionless temperature and nanoparticles concentration. The behavior of physical parameters on the temperature and nanoparticles concentrations is examined through graphs and tabular data. The temperature and concentration distribution at the surface are also computed and analyzed. It can be noted that both the temperature and nanomaterial are reduced for higher values of unsteadiness parameter. It is also observed that the friction factor of second grade fluid parameter is less compared with viscous nanofluid.

Time-dependent 3D flow of Maxwell nanofluid due to an unsteady stretching surface through porous space

In the present paper, we investigated unsteady three-dimensional flow of an incompressible magneto Maxwell nanomaterial in the porous medium. The cause of flow is unsteady stretching of sheet in transverse lateral directions taking zero mass flux of nanoparticles. The developed system of partial differential equations is transformed into nonlinear ordinary differential equations by similarity variables, and the obtained system is solved for dimensionless temperature and nanoparticles concentration by homotopy analysis method. The behavior of physical parameters on the temperature and nanoparticles concentrations is examined through graphs and tabular data. The temperature distribution at the surface is also computed and analyzed and noticed that both the temperature and nanomaterial are reduced for higher values of unsteadiness parameter.

Thermodynamics of Modified Cosmic Chaplygin Gas

We examine the thermodynamic features of an exotic fluid known as modified cosmic Chaplygin gas in the context of homogeneous isotropic universe model. For this purpose, the behavior of physical parameters is discussed that help to analyze nature of the universe. Using specific heat formalism, the validity of third law of thermodynamics is checked. Furthermore, with the help of thermodynamic entities, the thermal equation of state is also discussed. The thermodynamic stability is explored by means of adiabatic, specific heat and isothermal conditions from classical thermodynamics. It is concluded that the considered fluid configuration is thermodynamically stable and expands adiabatically for an appropriate choice of parameters.

Monitoring of Physical Parameters in Organic Waste Composting

The volume of biodegradable solid waste and its inadequate disposal have led to serious environmental problems, requiring efficient measures that prioritize the recycling of these wastes, promoting sustainability. The objective of this research was to monitor the behavior of physical parameters during the organic waste composting process. For this, 5 piles of organic waste were built through the composting technique developed according to the windrow method. The piles were composed of 70% of plant material, and 30% varied between manure and food remains. The piles were composed of 70% of plant material, and 30% varied between manure and food remains. The proportions were: I pile, 1:1 (15% manure and 15% rest of food); Pile II, 2:1 (20% manure and 10% rest of food); Cell III, 1:2 (10% manure and 20% rest of food); (30% manure and 0% rest of food) and the V pile in the ratio of 0:3 (0% manure and 30% rest of food). The evaluated parameters were temperature, moisture, pH, TOC, TN and C/N ratio. During the process of compost maturation, the parameters evaluated were kept within the established standards for the composting process.

Exact anisotropic polytropic cylindrical solutions

In this paper, we study anisotropic compact stars with static cylindrically symmetric anisotropic matter distribution satisfying polytropic equation of state. We formulate the field equations as well as the corresponding mass function for the particular form of gravitational potential $z(x)=(1+bx)^{\eta }~(\eta =1,~2,~3)$ and explore exact solutions of the field equations for different values of the polytropic index. The values of arbitrary constants are determined by taking mass and radius of compact star (Her X-1). We find that resulting solutions show viable behavior of physical parameters (density, radial as well as tangential pressure, anisotropy) and satisfy the stability condition. It is concluded that physically acceptable solutions exist only for $\eta =1,~2$ .

A first principles study of the mechanical, electronic, and vibrational properties of lead oxide

The first principles study of the crystal structure, chemical bonds, elastic and mechanical properties, electron energy band structure and density, and normal long-wave vibrations of nine phases of lead monoxide, dioxide, and tetraoxide has been performed under normal and external pressure within the framework of density functional theory (DFT) with the Perdew–Becke–Ernzerhof (PBE) gradient exchange-correlation functional and its hybrid version with a 25-% Hartree–Fock (HF) exchange contribution in the basis of localized atom orbitals. The behavior of physical parameters has been studied using the cold four- and threeparameter equations of state. The parameters of the crystal structures are in satisfactory agreement with experimental data, and elastic constants indicate their mechanical stability and anisotropy in the elastic properties. The elasticity, shear, and Young moduli, hardness, acoustic velocities, and Debye temperature of dioxide on the one hand and monoxide and tetraoxide on the other hand appreciably differ from each other. The difference between electron properties may be explained by the character of hybridization in the upper filled and lower empty energy bands as evident from the density of states. In monoxide, the indirect band gap width decreases with increasing pressure at a rate of 0.16 eV/GPa, and the direct band gap width increases at a rate of 0.13 eV/GPa. To identify crystalline phases, the frequencies and intensities of long-wave modes active in IR and Raman spectra have been calculated.

Boundary Layer Flow of Dusty Fluid on a Stretching Sheet of Another Quiescent Fluid

A research study on boundary layer flow of a dusty viscous fluid past a stretching sheet of another dusty viscous quiescent fluid is conducted. The upper lighter fluid imposes downward on a lower heavier fluid. The existence of solid particles in a dusty fluid either naturally or deliberately in the form of dust, ash or soot suspended in the fluid may influence both upper and lower fluid flow characteristic. Therefore, this study investigates the effects of specific physical parameters such as fluid particle interaction, stretching rate, suction and injection. The governing partial differential equations are transformed into ordinary differential equations by using similarity transformation. The resulting differential equations are solved numerically by using Finite Difference Method with Richardson Extrapolation. The behaviors of physical parameters on velocity profile as well as skin frictions are presented graphically.

Research and identification of dynamics and behaviour of physical parameters affecting the formation and level of electricity losses

У статті розглядається необхідність аналізу актуальної проблеми електричних втрат, які викликаються змінами атмосферних явищ: температури повітря та опадів. Вони негативно впливають на рівень втрат, що викликає необхідність дослідження проблеми. Наводиться приклад розрахунку втрат залежно від кількості опадів, температурних показників. Далі ці формули можна використовувати для виведення функцій для розрахунку втрат

Qualidade físico-hídrica de um latossolo sob irrigação e braquiária em lavoura de café no cerrado

The objective of this study was to evaluate the effect of irrigation and cultivation of brachiaria among coffee trees lines on physical-hydric Oxisol quality at Brazilian central plateau. The experiment was carried out in five randomized blocks in a factorial design 2 x 2, with two water treatments, irrigated and rainfed systems, and two management systems, with and without brachiaria between coffee trees lines. The research strategy was based on studying soil water storage based on porosity distribution due to the behavior of physical parameters in different water and management treatments. Soil samples were collected in duplicate in each plot at depths from 0.0 to 0.05, 0.05 to 0.10, 0.10 and 0.20 m. The irrigation regime increased soil bulk density in the surface layer without reducing its readily available water that, due to presence of brachiaria was increased by 18%. In general, irrigated brachiaria had a positive effect on the physical-hydric soil characteristics of the soil and promoted an increase in readly available soil microporosity from the redistribution of pore diameter characterized by increasing retention curve amplitude in the soil water tension range corresponding to the readily-available water.

The Hazards of Imaging Spectrophotometry with Interference Filters

Narrowband-filter imaging spectrophotometry is a powerful tool for studying the spatial behavior of physical parameters, such as interstellar reddening, excitation, electron temperature, and densities or chemical abundances across extended objects such as nebulae and galaxies. We explore the hazards and technical limits of the method of spectral imaging with narrowband interference filters. We discuss the specific application of statistical errors involved in the estimation of abundance gradients from nebular line flux measurements and the impact of those errors on interpretation. We demonstrate that a sample of at least 16 H II regions is needed for a meaningful and robust description of radial abundance gradients in disk galaxies. We also discuss the systematic errors introduced by the uncertainty related to the subtraction of the underlying stellar continuum from monochromatic emission-line images; we demonstrate that the quality of subtraction of the underlying continuum is the main limit on the precision of imaging spectrophotometry with narrowband filters. Finally, we investigate the impact of selection effects on the derivation of physical parameters from measurements involving the ratio of two or more spectral lines.

The effect of the magnetopause shapes of Jupiter and Saturn on magnetosheath parameters

The solar wind flow past nonaxisymmetric magnetospheres exhibits features which are absent in the case of axisymmetric magnetospheres such as that of Earth. We discuss results obtained by a numerical integration of the dissipationless MHD equations, under simplifying assumptions, and apply them to the two outer planets Jupiter and Saturn, both of whose magnetospheres depart substantially from axisymmetry. We model these magnetospheres as paraboloids with two different radii of curvature at the subsolar point, L 0 and L 1, where L 0 and L 1 refer to a magnetopause cut comtaining the rotational axis, and to the rotational equator, respectively ( L 0 < L 1). The degree of flattening is expressed by a parameter q:= L 0 L 1 , and, following earlier modelling and data analysis work, we set q = 0.35 for Jupiter and q = 0.64 for Saturn. We find here that the structure and behaviour of physical parameters in the magnetosheath of Saturn is intermediate to that at Earth and at Jupiter. For both planets, the thickness of the magnetosheath and the width and structure of the plasma depletion layer are found to be strong functions of the orientation of the interplanetary magnetic field (IMF). The effect of the IMF on the magnetosheath is strongest (weakest) when the IMF is directed perpendicular (parallel) to the rotational equator. For any intermediate orientation, a smooth rotation of the magnetosheath magnetic field towards the direction of the planet's rotational axis is superimposed on the field strength enhancement (and the density reduction) as the respective magnetopauses are approached. For Saturn, we study the dependence of magnetosheath parameters for various IMF orientations at two Alfvén Mach numbers. Throughout, we compare our results to similar calculations of solar wind flow past Earth.

Why DA and DB white dwarfs do not show coronal activity and p-mode oscillations

The problems of nonradiative heating of outer atmospheric layers and p-mode oscillations in white dwarfs caused by acoustic waves generated in convective zones are discussed. These effects have been studied by calculating the cutoff periods for adiabatic and isothermal waves propagating in atmospheres of DA and DB stars with Teff greater than or equal 20,000 K and log g = 6-9. The obtained cutoff periods are approximately bounded by 0.01 and 40 sec for high- and low-gravity white dwarfs, respectively. Expected amplitudes of p-mode oscillations corresponding to trapped acoustic waves with small angular wave numbers are estimated, indicating that the amplitudes could be observed as Doppler shifts of spectral lines which might be detectable if adequate spectral resolution were available. The luminosity variations corresponding to these amplitudes are unlikely to be observable when all damping processes are accounted for. Results also indicate that the present theory of convection predicts some irregularities in the behavior of physical parameters.