The thermal cracking of hydrocarbons for olefin production is carried out in long tubular reactors inserted in a furnace, in this process the heat flux along the reactor wall determines the feedstock conversion, the olefin selectivity's and rate of coke deposition. A detailed firebox simulation model is therefore a powerful tool in the design and operation of pyrolysis furnaces and reactors to ...

Abstract In the present paper, a theoretical analysis is made to investigate fluid flow and heat energy transformation features of single multi-walled water functionalized carbon nanotubes (CNTs) with uniform inconstancy boundary conditions onward flat plate. The liquid motion momentum transfer have been analyzed using homogeneous model. Both single-wall CNTs (SWCNTs) multi-wall (MWCNTs) used b...

We discuss the structure of the equilibrium states of a regularized Keller-Segel model describing the chemotaxis of bacterial populations. We consider the limit of high degradation of the secreted chemical where analytical results can be obtained. Below a critical effective temperature, the system experiences a second order phase transition from a homogeneous phase to an inhomogeneous phase for...

The design of retaining walls depends on the magnitude of active pressure exerted from the backfill. Therefore, estimating the scale of this pressure is a fundamental factor in the design. In this study, to assess the active earth pressure, a rigid retaining wall was built capable of translating and/or rotating with adjustable speed. Further, several physical tests were conducte...

This study investigates the unsteady flow of Powell-Eyring fluid past an inclined stretching sheet. Unsteadiness in the flow is due to the time-dependence of the stretching velocity and wall temperature. Mathematical analysis is performed in the presence of thermal radiation and non-uniform heat source/sink. The relevant boundary layer equations are reduced into self-similar forms by suitable t...

This study aims to investigate the formability of AA2198-T3 Al-Li alloy in hydro-mechanical deep drawing (HMDD), through experimentation and finite element simulation. The effects most critical factors were studied: die cavity pressure forming temperature; temperature is selected at 298K 423K. Gurson?Tvergaard?Needleman model (GTN model) was employed analyze predict fracture hydroforming a cyli...

A numerical solution to the entropy generation in a circular pipe is made. Radial and axial variations are considered. Navier-Stokes equations in cylindrical coordinates are used to solve the velocity and temperature fields. Uniform wall heat flux is considered as the thermal boundary condition. The distribution of the entropy generation rate is investigated throughout the volume of the fluid a...

We investigate the thermodynamics and dynamics of the electroweak phase transition by modelling the infrared physics with classical Yang-Mills Higgs theory. We discuss the accuracy of this approach and conclude that, for quantities whose determination is dominated by the infrared, the classical method should be correct up to parametrically suppressed (ie O(α)) corrections. For a Higgs self-coup...

We investigate the thermodynamics and dynamics of the electroweak phase transition by modelling the infrared physics with classical Yang-Mills Higgs theory. We discuss the accuracy of this approach and conclude that, for quantities whose determination is dominated by the infrared, the classical method should be correct up to parametrically suppressed (ie O(α)) corrections. For a Higgs self-coup...