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This paper reviews and compares the methods of kinetic heat simulation which may be used simultaneously with normal loading in structural tests of aircraft or components. Basic data on the quantities involved in and the limitations of the various techniques are given. An extensive bibliography of current literature on heat technology is provided.

This paper presents the results of a numerical simulation of measured heat losses from a real building. In particular, the thermal response of a concrete ground floor slab and the underlying foundation soils has been analysed and the results calibrated against data acquired from a comprehensive long term in‐situ monitoring experiment. A numerical solution of a heat conduction model is obtained by use of the finite element method. Finite differences are used to accommodate the time varying nature of the problem. The model has been applied to the simulation of transient one‐dimensional behaviour. Diurnal and seasonal variations in temperature are considered. Good correlation between predicted and measured thermal response has been achieved. It is, therefore, claimed that the modelling approach adopted is capable of representing real in‐situ behaviour.

In this paper, analytical modelling of heat distribution along the thickness of different printed circuit board (PCB) substrates is presented according to the 1 D heat transient conduction problem. This paper aims to reveal differences between the substrates and the geometry configurations and elaborate on further application of explicit modelling.

Different substrates were considered: classic FR4 and polyimide, ceramics (BeO, Al₂O₃) and novel biodegradables (polylactic-acid [PLA] and cellulose acetate [CA]). The board thicknesses were given in 0.25 mm steps. Results are calculated for heat transfer coefficients of convection and vapour phase (condensation) soldering. Even heat transfer is assumed on both PCB sides.

It was found that temperature distributions along PCB thicknesses are mostly negligible from solder joint formation aspects, and most of the materials can be used in explicit reflow profile modelling. However PLA shows significant temperature differences, pointing to possible modelling imprecisions. It was also shown, that while the difference between midplane and surface temperatures mainly depend on thermal diffusivity, the time to reach solder alloy melting point on the surface depends on volumetric heat capacity.

Results validate the applicability of explicit heat transfer modelling of PCBs during reflow for different heat transfer methods. The results can be incorporated into more complex simulations and profile predicting algorithms for industrial ovens controlled in the wake of Industry 4.0 directives for better temperature control and ultimately higher soldering quality.

Most of the industrial buildings which are designed to moderate loads are constructed using light gauge cold-formed steel (CFS) sections. Residual mechanical properties of CFS sections exposed to elevated temperature need to be investigated as it is necessary to predict the deterioration of elements to avoid failure of the structure or its elements. Also, it would be helpful to decide whether the structural elements need to be replaced or reused. The use of fire-resistant coatings in steel structures significantly reduces the cost of repairing structural elements and also the probability of collapse. This study investigates the effect of fire-resistant coating on post-fire residual mechanical properties of E350 steel grade.

In this study, an attempt has been made to evaluate the residual mechanical properties of E350 steel. A tensile coupon test was performed for the extracted specimens from the exposed CFS section to determine the mechanical properties. Four different fire-resistant coatings were selected and the sections were coated and heated as per ISO 834 fire temperature curve in the transient state for time durations of 30 minutes (821°C), 60 minutes (925°C), 90 minutes (986°C), and 120 minutes (1,029°C). After the exposure, all the coupon specimens were cooled by either ambient conditions (natural air) or water spraying before conducting the tension test on these specimens.

At 30 min exposure, the reduction in yield and ultimate strength of heated specimens was about 20 and 25% for air and water-cooled specimens compared with reference specimens. Specimens coated with vermiculite and perlite exhibited higher residual mechanical property up to 60 minutes than other coated specimens for both cooling conditions. Generally, water-cooled specimens had shown higher strength loss than air-cooled specimens. Specimens coated with vermiculite and perlite showed an excellent performance than other specimens coated with zinc and gypsum for all heating durations.

As CFS structures are widely used in construction practices, it is crucial to study the mechanical properties of CFS under post-fire conditions. This investigation provides detailed information about the physical and mechanical characteristics of E350 steel coated with different types of fire protection materials after exposure to elevated temperatures. An attempt has been made to improve the residual properties of CFS using the appropriate coatings. The outcome of the present study may enable the practicing engineers to select the appropriate coating for protecting and enhancing the service life of CFS structures under extreme fire conditions.

To investigate the effect of transient mixed convective flow interaction between circular cylinders and channel walls on heat transfer with three circular cylinders arranged in an isosceles right‐angled triangle within a horizontal channel.

This paper uses a semi‐implicit finite element method to solve the incompressible Navier‐Stokes equation, energy equation and continuity equation in primitive‐variable form by assuming the flow to be two‐dimensional and laminar.

Provides information indicating that the transient streamlines, isotherms, drag coefficient and time‐mean Nusselt number around the surfaces of three cylinders are affected by various gap‐to‐diameter ratio, Reynolds numbers and Grashof numbers. The results show that the maximum value of surface‐ and time‐mean Nusselt number along cylinders exists at S=0.75.

It is limited to two‐dimensional laminar flow for the transient mixed convective flow interaction between circular cylinders and channel walls in a horizontal channel.

A very useful source of information and favorable advice for people is applied to heat exchangers, space heating, power generators and other thermal apparatus.

The results of this study may be of interest to engineers attempting to develop thermal control of thermal apparatus and to researchers interested in the flow‐modification aspects of mixed convection between circular cylinders and channel walls in a horizontal channel.

The paper presents a finite‐difference scheme to solve the transient conjugated heat transfer problem in a concentric annulus with simultaneously developing hydrodynamic and thermal boundary layers. The annular forced flow is laminar with constant physical properties. Thermal transient is initiated by a step change in the prescribed isothermal temperature of the inner surface of the inside tube wall while the outer surface of the external tube is kept adiabatic. The effects of solid‐fluid conductivity ratio and diffusivity ratio on the thermal behaviour of the flow have been investigated. Numerical results are presented for a fluid of Pr = 0.7 flowing in an annulus of radius ratio 0.5 with various values of inner and outer solid wall thicknesses.

This paper aims to study the impacts of viscous dissipation, thermal radiation and Joule heating on squeezing flow current and the heat transfer mechanism for a magnetohydrodynamic (MHD) nanofluid flow in parallel disks during a suction/blowing process.

First, the governing momentum/energy equations are transformed into a non-dimensional form and then the obtained equations are solved by modified Adomian decomposition method (ADM), known as Duan–Rach approach (DRA).

The effect of the radiation parameter, suction/blowing parameter, magnetic parameter, squeezing number and nanoparticles concentration on the heat transfer and flow field are investigated in the results. The results show that the fluid velocity increases with increasing suction parameter, while the temperature profile decreases with increasing suction parameter.

A complete analysis of the MHD fluid squeezed between two parallel disks by considering Joule heating, thermal radiation and adding different nanoparticles using the novel method called DRA is addressed.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

In heavy industrial sewing, needle heating has become a serious problem that limits the further increase of the sewing speed, and hence the productivity. The high temperature in the needle can degrade the strength of the thread. At the same, it may cause the wear of the needle eye, which would further damage the thread. It can also scorch the fabric, as well as temper and weaken the needle itself. Therefore, it is important to develop a model that can predict the needle heating and, hence, find remedies to minimize its effects. According to a literature survey, most research on needle heating focuses on experimental methods, such as infrared radiometry, infrared pyrometry, etc. This paper is the first part of our research on needle heating. In this paper, two analytical models are presented: the sliding contact model and the lumped variable model. These models are relatively simple and easy to use. Given needle geometry, sewing condition, and fabric characteristic, they can predict the needle temperature rise starting from initial heating to steady state. The simulation results are rather accurate. Hence, the models can be used to quickly identify the potential needle heating problems on the shop floor. In Part 2 of our study, a finite element analysis (FEA) model is presented together with the experiment results.

The purpose of this study is to clarify the mechanism of ambient and transient temperature effects on piezoelectric pressure sensors, and to propose corresponding compensation measures. The temperature of the explosion field has a significant influence on the piezoelectric sensor used to measure the shock wave pressure. For accurate shock wave pressure measurement, based on the actual piezoelectric pressure sensors used in the explosion field, the effects of ambient and transient temperatures on the sensor should be studied.

The compensation method of the ambient temperature is discussed according to the sensor size and material. The theoretical analysis method of the transient temperature is proposed. For the transient temperature conduction problem of the sensor, the finite element simulation method of structure-temperature coupling is used to solve the temperature distribution of the sensor and the change in the contact force on the quartz crystal surface under the step and triangle temperatures. The simulation results are highly consistent with the theory.

Based on the analysis results, a transient temperature control method is proposed, in which 0.5 mm thick lubricating silicone grease is applied to the sensor diaphragm, and 0.2 mm thick fiberglass cloth is wrapped around the sensor side. Simulation experiments are carried out to verify the feasibility of the control method, and the results show that the control method effectively suppresses the output of the thermal parasitic.

The above thermal protection methods can effectively improve the measurement accuracy of shock wave pressure and provide technical support for the evaluation of the power of explosion damage.