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This paper addresses the themes of resistance to soldering heat and heat dissipation as aspects of reliability in relation to surface mounted devices soldered on a plastic substrate by the most common industrial processes. Reliability data are presented for devices soldered by double wave, multiple wave, vapour phase and infra‐red processes and comments given on the reliability results. In terms of heat dissipation, using an internally developed test pattern and suitable test boards, a study was made of the influence of the substrate on thermal dissipation, thermal impedance, and new medium power SO and PLCC packages offering the possibility of cost‐effective power dissipation in the range of 1.5–2 W while still maintaining a standard outline.

The purpose of this paper is to analyze the thermal shock response on the deformation of circular hollow cylinder in a thermodynamically consistent manner.

The investigation is carried out under the light of generalized thermoelasticity theory with energy dissipation. In order to obtain the analytical expressions of the components of stress and strain fields, appropriate integral transform technique is adopted and the salient features are emphasized.

It has been observed that the existence of energy dissipation can minimize the development of the stress components into the cylindrical wall. Since more amount of heat is propagate into the medium in a short period of time consequently, the medium deformed in a high rate in presence of energy dissipation. Two special phenomena are also revealed in the particular cases.

The numerical simulated results are demonstrated through a numerous diagrams and some important observations are explained. This work may be helpful for those researchers who are devoted on several types of heat or fluid flow into the pipeline made with anisotropic solids.

One of the major challenges in the design of thermal equipment is to minimize the entropy production and enhance the thermal dissipation rate for improving energy efficiency of the devices. In several industrial applications, the structure of thermal device is cylindrical shape. In this regard, this paper aims to explore the impact of isothermal cylindrical solid block on nanofluid (Ag – H₂O) convective flow and entropy generation in a cylindrical annular chamber subjected to different thermal conditions. Furthermore, the present study also addresses the structural impact of cylindrical solid block placed at the center of annular domain.

The alternating direction implicit and successive over relaxation techniques are used in the current investigation to solve the coupled partial differential equations. Furthermore, estimation of average Nusselt number and total entropy generation involves integration and is achieved by Simpson and Trapezoidal’s rules, respectively. Mesh independence checks have been carried out to ensure the accuracy of numerical results.

Computations have been performed to analyze the simultaneous multiple influences, such as different thermal conditions, size and aspect ratio of the hot obstacle, Rayleigh number and nanoparticle shape on buoyancy-driven nanoliquid movement, heat dissipation, irreversibility distribution, cup-mixing temperature and performance evaluation criteria in an annular chamber. The computational results reveal that the nanoparticle shape and obstacle size produce conducive situation for increasing system’s thermal efficiency. Furthermore, utilization of nonspherical shaped nanoparticles enhances the heat transfer rate with minimum entropy generation in the enclosure. Also, greater performance evaluation criteria has been noticed for larger obstacle for both uniform and nonuniform heating.

The current numerical investigation can be extended to further explore the thermal performance with different positions of solid obstacle, inclination angles, by applying Lorentz force, internal heat generation and so on numerically or experimentally.

A pioneering numerical investigation on the structural influence of hot solid block on the convective nanofluid flow, energy transport and entropy production in an annular space has been analyzed. The results in the present study are novel, related to various modern industrial applications. These results could be used as a firsthand information for the design engineers to obtain highly efficient thermal systems.

This paper aims to deduce a set of theory computational formula, and optimize and improve the heat conductivity of vias in printed circuit boards of electrical power apparatus.

The authors adopted numerical simulation and experimental measurement to verify the reliability of this formula.

Research result showed that 0.45 mm was the optimal bore diameter of vias; the conductivity had no obvious improvement when filling material was FR4 or Rogers, but if it was filled with texture of high thermal conductivity like soldering tine, the conductivity would improve a lot; the plating thickness of vias had a greater influence on thermal conductivity.

Through the theory computational formula, this paper studied the influence of aperture of vias, filled materials and thickness of copper plated on vias on thermal conductivity.

Thermal management under high heat flux is crucial to developing high‐power light‐emitting diode (LED) applications. The purpose of this paper is to propose an efficient thermal dissipation technique for an LED back light unit (BLU) system.

A typical BLU system includes an LED package (GaN on sapphire, cathode/anode, silicone encapsulant, resin plus phosphor) on a printed circuit board (PCB), a light guide panel, and an aluminum cover frame. The temperature distribution of this system has been simulated and the thermal behavior within a 3D model has been investigated using a commercial computational fluid dynamic code (FLUENT 6.3).

The authors examined the heat‐spreading effect of cover lengths ranging from 6 to 300 mm and also observed the effect of back cover thickness on the junction temperature and cover frame temperature and investigated the influence of the air gap between the package and the cover frame. Removing the air gap lowers the maximum temperature by about 6 percent. It was found that the addition of a copper layer covering the external surfaces of the LED chip enhanced the cooling efficiency. Finally, the maximum junction temperature can be decreased by more than 21 percent in the range of parameters considered by removing the air gap, adding a heat spreader, and using a thick cover frame.

In this paper, thermal management for efficient heat spreading through a typical BLU system without using any additional devices is investigated. Several parameters that increase the system's temperature are examined, and a combination of design features that attenuate the junction temperature is proposed.

The purpose of this paper is to form copper coin-embedded printed circuit board (PCB) for high heat dissipation.

Manufacturing optimization of copper coin-embedded PCB involved in the design and treatment of copper coin, resin flush removal and flatness control. Thermal simulation was used to investigate the effect of copper coin on heat dissipation of PCB products. Lead-free reflow soldering and thrust tests were used to characterize the reliable performance of copper coin-embedded PCB.

The copper coin-embedded PCB had good agreement with resin flush removal and flatness control. Thermal simulation results indicated that copper coin could significantly enhance the heat-dissipation rate by means of a direct contact with the high-power integrated circuit chip. The copper coin-embedded PCB exhibited a reliable structure capable of withstanding high-temperature reflow soldering and high thrust testing.

The use of a copper coin-embedded PCB could lead to higher heat dissipation for the stable performance of high-power electronic components. The copper coin-embedded method could have important potential for improving the design for heat dissipation in the PCB industry.

This paper aims to present a high-order algorithm implemented with the modal spectral element method and simulations of three-dimensional thermal convective flows by using the full viscous dissipation function in the energy equation. Three benchmark problems were solved to validate the algorithm with exact or theoretical solutions. The heated rotating sphere at different temperatures inside a cold planar Poiseuille flow was simulated parametrically at varied angular velocities with positive and negative rotations.

The fourth-order stiffly stable schemes were implemented and tested for time integration. To provide the hp-refinement and spatial resolution enhancement, a modal spectral element method using hierarchical basis functions was used to solve governing equations in a three-dimensional space.

It was found that the direction of rotation of the heated sphere has totally different effects on drag, lateral force and torque evaluated on surfaces of the sphere and walls. It was further concluded that the angular velocity of the heated sphere has more influence on the wall normal velocity gradient than on the wall normal temperature gradients and therefore, more influence on the viscous dissipation than on the thermal dissipation.

This paper concerns incompressible fluid flow at constant properties with up to medium temperature variations in the absence of thermal radiation and ignoring the pressure work.

This paper contributes a viable high-order algorithm in time and space for modeling convective heat transfer involving an internal heated rotating sphere with the effect of viscous heating.

Results of this paper could provide reference for related topics such as enhanced heat transfer forced convection involving rotating spheres and viscous thermal effect.

The merits include resolving viscous dissipation and thermal diffusion in stationary and rotating boundary layers with both h- and p-type refinements, visualizing the viscous heating effect with the full viscous dissipation function in the energy equation and modeling the forced advection around a rotating sphere with varied positive and negative angular velocities subject to a shear flow.

This paper aims to investigate entropy generation in an incompressible magneto-micropolar nanofluid flow over a nonlinear stretching sheet. The flow is subjected to thermal radiation and viscous dissipation. The energy equation is extended by considering the impact of the Joule heating term because of an imposed magnetic field.

The flow, heat and mass transfer model are solved numerically using the spectral quasilinearization method. An analysis of the performance of this method is given.

It is found that the method is robust, converges fast and gives good accuracy. In terms of the physically significant results, the authors show that the irreversibility caused by the thermal diffusion the dominants other sources of entropy generation and the surface contributes significantly to the total irreversibility.

The flow is subjected to a combination of a buoyancy force, viscous dissipation, Joule heating and thermal radiation. The flow equations are solved numerically using the spectral quasiliearization method. The impact of a range of physical and chemical parameters on entropy generation, velocity, angular velocity, temperature and concentration profiles are determined. The current results may help in industrial applicants. The present problem has not been considered elsewhere.

This paper aims to analyze the effect of absorber’s geometry and operating fluid on the thermal and hydrodynamic behaviors of a solar collector. Two different profiles are proposed for the absorber which is wavy and flat. Also, the inner tube of HTF (i.e. heat transfer fluid) is considered as single and double. The solar collector is filled with hybrid nanofluid of SiO₂-TiO₂/ ethylene glycol (EG) which its thermal conductivity and dynamic viscosity are measured using KD2 Pro and Brookfield LVDV III Ultra; respectively, in the temperature range of 30°C to 80°C and nanoparticle concentration in the range of 1.5% to 3.5%.

Among the solar collector, the parabolic-trough solar collector is one of the most efficient models for extracting solar thermal power. A parabolic trough solar collector with two different models of absorbers and included with two models of inner HTF tube is proposed.

The corresponding regression equations are derived versus temperature and volume fraction and used in the numerical process. For the numerical process, the thermal lattice Boltzmann method manipulated with a single-node curved scheme is used. Also, in the final step, the second law analysis is carried out in local and volumetric forms. The influential factors are Rayleigh number, the concentration of hybrid nano-powder and the structure of absorber profile.

The originality of the present work is combining a modern numerical method (i.e. double-population lattice Boltzmann method) with experimental observation on characteristics of SiO₂-TiO₂/EG nanofluid to analyze the thermal performance of parabolic trough solar collector.

The purpose of this paper is to examine the effect of non-linear thermal radiation, Joule heating and viscous dissipation on the mixed convection boundary layer flow of MHD nanofluid flow over a thin moving needle.

The equations directing the flow are reduced into ODEs by implementing similarity transformation. The Runge–Kutta–Fehlberg method with a shooting technique was implemented.

Numerical outcomes for the coefficient of skin friction and the rate of heat transfer are tabulated and discussed. Also, the boundary layer thicknesses for flow and temperature fields are addressed with the aid of graphs.

Till now, no numerical study investigated the combined influence of Joule heating, non-linear thermal radiation and viscous dissipation on the mixed convective MHD flow of silver-water nanofluid flow past a thin moving needle. The numerical results for existing work are new and their novelty verified by comparing them with the work published earlier.