Heat - Science topic

The lack of drinking water is a major problem in many parts of the world, and solar distillation can be an effective solution. Solar distillation is a simple process that uses the energy from the sun to evaporate water and then collect the condensed vapor, leaving behind impurities. Ethanol has a lower boiling point than water, which means it evapo...

In the context of racing to carbon neutrality, the pipe-embedded building system makes the opaque envelopes gradually regarded as the multi-functional element, which also provides an opportunity for thermal insulation solutions to transform from high to zero-carbon attributes. Based on the re-examination of the heat transfer process of conventional...

Determining the ignition temperature of combustible substances is crucial in enhancing energy utilization efficiency and preventing fire and explosion accidents. This study investigates the ignition temperature of ethane-air mixtures with concentrations of 29.6%, 31.8%, and 34.4% at pressures up to 1 MPa in a 20 L spherical closed vessel, using a "...

The paper focuses on the flow structures and mass flow rates of thermally driven smoke flows induced by fires in long transportation tunnels under natural ventilation. The important influencing factors including heat release rate (HRR), tunnel width and height, are taken into consideration. The mechanism of the smoke flow movement is explored. The...

With the ongoing significance of overheating calculations in the residential building sector, building codes such as the European Energy Performance of Building Directive (EPBD) are essential for harmonizing the indicators and performance thresholds. This paper investigates Europe's overheating calculation methods, indicators, and thresholds and ev...

Compacting phase change materials (PCMs) for thermal energy management in buildings is a promising method to reduce peak temperature and heat gain in hot climates. This experimental study analyses the hourly temperature reduction (HTR) and hourly heat gain reduction (HHGR) of building envelope-compacted PCM passively during a hot summer day. Two cu...

In this work, an in-line strip-fin manifold microchannel heat sink is proposed to improve the hydrodynamic and thermal performance of the conventional manifold microchannel. The hydrodynamic and thermal performance of varying strip-fin arrangements with approximately the same heat transfer area are numerically investigated. The results show that th...

This article presents the results of experiments and finite element analysis on a hybrid polymer gear concept. The study aimed to investigate the effectiveness of the hybrid gear concept by using a rack tooth geometry. The results of the experiments have shown that the hybrid gear concept improves the heat evacuation from the flank and root regions...

In this study, a novel type of air-cooled heat sink is proposed, which consists of several layers of mini-channels. In this design, the hydraulic diameter is smaller than in conventional types of heat sinks, such as plate-fin heat sinks, and consequently, the achievable heat transfer rates are higher. To predict the cooling performance of this heat...

The Porter Five Forces Analysis is a framework for evaluating the degree of industry competitiveness and the creation of corporate strategies. It derives five forces from organization that control the level of competition and a market's attractiveness. It was found that fierce competition is a major worry for RB Patel. Threats from new entrants are...

Swedana (Fomentation) is one of the six therapeutic procedures. It is performed with heat or without thirteen types of with heat (Agni) Sweda types are observed. As advancement in technology traditional method are developed and new way, tools and instruments are used by doctors. Current study is planned with objective to compile review and compare...

The capability of tailoring the resonance wavelength of metasurfaces is important as it can alleviate the manufacturing precision required to produce the exact structure according to the design of the nanoresonators. Tuning of Fano resonances by applying heat has been theoretically predicted in the case of silicon metasurfaces. Here, we experimenta...

This study explores the application of zigzag-shaped, finless tubes in enhancing heat transfer performance within heat exchangers. Using three-dimensional numerical simulations, we examined the heat transfer per unit area and the volume of the pressure drop, comparing these findings with a traditional parallel tube heat exchanger. This innovative d...

We consider the Cauchy problem for heat equation with fractional harmonic oscillator and exponential nonlinearity. We establish local well-posedness result in Orlicz spaces. We derive the existence of global {weak-mild} solutions for small initial data and obtain decay estimates for large time in Lebesgue spaces. In particular, we show that the dec...

We prove a weak Harnack estimate for a class of doubly nonlinear nonlocal equations modelled on the nonlocal Trudinger equation \begin{align*} \partial_t(|u|^{p-2}u) + (-\Delta_p)^s u = 0 \end{align*} for $p\in (1,\infty)$ and $s \in (0,1)$. Our proof relies on expansion of positivity arguments developed by DiBenedetto, Gianazza and Vespri adapted...

A viscous fluid is confined between two smooth horizontal walls, in a vertical channel. The upper wall may move with constant speed, but the lower wall is stationary and a portion of it is heated. A plume of heated fluid develops, and may also be swept downstream by the motion of the upper wall. When the heating effect is small and the upper plate...

Studying the impact of various factors on environmental perception is crucial because humans live in an environment where these factors interact and blend. The thermal-acoustic environment is the major factor that affects the overall perception of urban parks. This study focuses on urban parks in the subtropical region, with Xihu Park in Fuzhou, Ch...

Changes in the morphology of betulin crystals during heating at selected temperatures corresponding to polymorphic transformations were investigated. It was shown that the prismatic crystals of starting betulin form III were converted into needles at 120 °C after water removal, followed by the III→II polymorphic transformation. During further heati...

The temperature distribution in a conductive-radiative rectangular profiled annular fin with internal heat generation is scrutinized in the present investigation. The nonlinear variation of thermal conductivity and heat transfer coefficient governed by the power law is considered. The analytical approximation for the non-dimensional temperature pro...

In this paper, we proposed a model in which a single level of two quantum dots is connected in parallel and embedded between two leads with diferent temperatures and chemical potentials. Te temperature and chemical potential gradient help the electron fow cyclically and act as a heat engine. We explore the thermodynamic properties of the model such...

Objective To explore the frequency and effect of extreme temperature on the non-accidental death rate in Hulunbuir, a Chinese ice city. Methods From 2014 to 2018, mortality data of residents residing in Hulunbuir City were collected. The lag and cumulative effects of extreme temperature conditions on non-accidental death and respiratory and circul...

Observations collected with the Atacama Large Millimeter/submillimeter Array (ALMA) and analysis of broadband X-ray spectra have recently suggested the presence of a central compact object (CCO) in SN 1987A. However, no direct evidence of the CCO has been found yet. Here we analyze Chandra X-ray observations of SN 1987A collected in 2007 and 2018,...

Stacked plate heat exchangers are widely used in thermal energy storage systems and a comprehensive and accurate analysis is necessary for their application and optimization. The fluid flow distribution between the plates is important to ensure even and full usage of the thermal energy storage potential. However, due to the complex topography of th...

The Swiss-type lathe is a specialized turning machine of Swiss-origin with a wide range of applications across the precision machining industry. Its unique features enable it to mass produce parts at high speeds and with high precision. However, the complex non-symmetric structure of the machine tool makes it particularly susceptible to the adverse...

In this paper we consider a system coupling a wave equation with a heat equation through its boundary conditions. The existence of a small parameter in the heat equation, as a factor multiplying the time derivative, implies the existence of different time scales between the constituents of the system. This suggests the idea of applying a singular p...

Milling is a complex process where machining quality is influenced by tool geometry, chip flow, temperature, and wear. In recent years, the rapid development of computer technology has enabled the use of finite element simulation methods to study the relationship between the machining results and various process parameters. In this study, a three-d...

Temperature is one of the most important factors to consider while researching the climate, as it is a crucial factor in the occurrence of changes in other climatic variables. Due to the fluctuating temperatures throughout the year in the geographical location of Iraq, it is critical that we investigate temperature variations and other climatic fac...

The Arctic warms much faster than other places under increasing greenhouse gases, a phenomenon known as Arctic amplification (AA). Arctic positive lapse-rate feedback (LRF) and oceanic heating induced by sea-ice loss have been considered as major causes of Arctic warming and AA, and Arctic high atmospheric stability has been considered as a key fac...

High temperatures and heatwaves caused by climate change and rapid urbanization are major environmental issues affecting the health of urban populations, especially in metropolitan areas. However, previous studies on heat health risk (HHR) have mainly focused on a single time or a simple indicator, with few studies using a systematic risk assessmen...

We study a system composed of two quantum dots connected in series between two leads at different temperatures, in the limit of large intratomic repulsion. Using the non-crossing approximation, we calculate the spectral densities at both dots $\rho_i(\omega)$, the thermal and thermoelectric responses, thermopower and figure of merit in different re...

Background Previous studies have suggested that ambient temperature is associated with the morbidity and mortality of stroke although results among these investigations remained unclear. Therefore, the purpose of present meta‐analysis was to summarize the evidence of the relationship between ambient temperature and stroke morbidity and mortality....

Two-dimensional magnets have manifested themselves as promising candidates for quantum devices. We here report that the edge and strain effects during the device fabrication with two-dimensional honeycomb ferromagnets such as CrX$_3$ (X=Cl, I, Br) and CrXTe$_3$ (X=Si, Ge) can be characterized by a (1+1)-dimensional magnon chiral anomaly beyond the...

The characteristics of forced convection heat transfer across a row of heated square cylinders kept in side‐by‐side arrangement are numerically investigated to examine the combined effects of Reynolds number and cylinder spacing for Ri = 0, 60 ≤ Re ≤ 160, Pr = .71, and s/d = 1.0–8.0, where the space between cylinder surfaces is s and the cylinder s...

In this paper the temperature distribution in two CPU sink devices is evaluated using the finite element method. The influence of the geometry, heat power dissipated by the CPU, heat sink materials, fan speed and environment temperature are evaluated.

An algorithm for calculating the temperature regime of heliochambers for heliothermal treatment of concrete has been compiled. The algorithm includes heat release when cement is dissolved in water, since the change in heat release power when cement is dissolved in water is also subjected to harmonic analysis. Comparing the results obtained on a com...

Purpose and Methodology: The heat transport investigation in non-Newtonian fluids suspended by distinct sort of nanoparticles is a rich motive in the present time. Therefore, inspired by the physical characteristics of base fluid and ternary nanoparticles (Al2O3-CuO-Cu), a comprehensive analysis conducted over a cylinder with wavy radius with speci...

This article explores the measurement of temperature in transient states, utilizing the principles of heat transfer and thermal-electrical metaphor. The study focuses on the nonlinear thermal resistances present in various locations within a distribution transformer, while taking into account variations in oil physical variables and temperature los...

Thermoelectric cooling can quickly and efficiently remove heat from a central processing unit (CPU) to prevent its failure. However, simultaneous optimization of the cooling capacity and efficiency in the CPU cooling system remains a challenge. Here, a dual-thermoelectric-liquid hybrid system for the CPU cooling is designed to overcome this challen...

The existence of item bias in a set of measuring instruments can threaten the instrument’s validity. Based on the Rasch model, this study evaluated item bias in the four-tier heat and temperature diagnostic test (4T-HTDT). This study used a cross-sectional quantitative survey method. There were 241 students selected using a stratified random sampli...

Les changements climatiques font évoluer à la fois la géographie des risques et celle des atouts des territoires français. Il en résulte deux types principaux de migra-tions climatiques qui appellent une politique d’aménagement du territoire adaptée à la diversité des mutations. Climate change is changing both the geography of risks and the geogra...

The gas-steam power plant combines a gas power plant and a steam power plant, where Heat Recovery Steam Generator (HRSG) is a unit for generating steam. The waste heat from this system is channelled to the chimney with a Thermoelectric Generator (TEG) module to generate electrical energy. TEG uses the waste heat from the thermal conduction process...

Artificial Intelligence Generated Content (AIGC) is one of the latest achievements in AI development. The content generated by related applications, such as text, images and audio, has sparked a heated discussion. Various derived AIGC applications are also gradually entering all walks of life, bringing unimaginable impact to people's daily lives. H...

Ti-6Al-4V titanium alloy weldments were prepared by the conventional TIG and fast frequency double pulse TIG (FFDP TIG) waveforms. Arc shape, microstructure and mechanical properties of weldments were investigated. The arc core area of the FFDP TIG shrink gradually, the weldment fusion zone (FZ) width and heat affected zone (HAZ) width reduced by 1...

The article covers the problem of determination of loads of blast wave on aboveground and underground structures. In industrial production, the chemical sources of explosion occur, for which the environment is air. The most common and typical source of explosion is solid products of the explosion (PE) in the form of a packed charge. In a chemical e...

The task of this research cycle was to measure adsorption isotherms (а) in the temperature range from 273 to 373 K, based on isotherms measured at different temperatures, to calculate isosteric heats (Qd) and entropies (∆Sd) of adsorption in order to select an effective adsorbent for purifying natural gas and oil products from sulfur-containing com...

In this work, the influence of the tool geometry on friction stir spot welding (FSSW) was studied on sheets made of AA6061-T6 aluminum alloy. Four different AISI H13 tools with simple cylindrical and conical pin profiles and 12 mm and 16 mm shoulder diameters were used to perform the FSSW joints. Sheets of 1.8 mm thickness were used during the expe...

This is my first attempt to communicate with the ChatGPT4 on the caloric theory of heat. ChatGPT4 reacted promptly with a good overview of this topic. ChatGPT4 during our half hour conversation brought a new view to this topic with some unknown references to the author of this contribution. ChatGPT4 can be promising support to improve the literatur...

The article is devoted to the research of the effect of the prismatic nozzle design on the large phase contact surface while steam nozzle is used to spray the mistella in the inner cavity of the final distiller. The appearance of the dispersed phase in spraying liquid in a prismatic four-nozzle sprayer was analyzed in the experimental equipment ass...

Pseudo-binary electrolytes of (100 − x)Li4GeO4·xLi3VO4 (x = 0, 10, 20, 30, 40, and 50 mol %) and pseudo-ternary electrolytes of 45Li4GeO4·45Li3VO4·10LiaMOb (M = B, Si, P, S, Mo, and W) with lithium superionic conductor (LISICON) type structures were prepared by mechanochemical treatment and subsequent heat treatment. For the (100 − x)Li4GeO4·xLi3VO...

Superabsorbent polymers (SAPs) are used as a soil amendment for retaining water, but suitable methods for the application of SAPs have not yet been developed. Here, we characterized a variety of soil–SAP mixtures prepared using four different types of SAP in terms of their water absorption and release characteristics. The teabag method was applied...

In the construction process of an asphalt concrete impermeable core wall, the interlayer bonding of the core wall is the weak link of the core wall structure and also the focus of construction, so it is important to carry out research on the influence of interlayer bonding temperature on the bending performance of an asphalt concrete core wall. In...

The purpose of this research is to correctly model steady-state heat transfer in and around rectangular bus bars installed horizontally in an indoor environment and to estimate the corresponding ampacities, considering the effects of horizontal transverse vibrations caused by electromagnetic forces. This thermo-electro-magneto-mechanical problem is...

This article covers the results of a study on the determination of the differential heat, isotherm and entropy of water vapor in ZSM-5 zeolites at a temperature of 303 K using the adsorption-calorimetric method. The type and number of ion-molecular formed complexes, as well as the mechanism of adsorption of the studied molecules, were determined. B...

This review presents an update on the physical, chemical, and biological properties of food allergens in plant sources, focusing on the few protein families that contribute to multiple food allergens from different species and protein families recently found to contain food allergens. The structures and structural components of the food allergens i...

The article deals with the issue of increasing the efficiency of the drying plant, gives theoretical prerequisites and analytical calculations and a generalized formula for determining thermal efficiency is derived. The author and the staff conducted a number of experiments on a pilot plant. According to the results of the experiments, curves of th...

Dry dispersible substances are used as raw materials in almost all branches of production, mainly in chemical, pharmaceutical, food, construction and other industries. Therefore, there is always a need for facilities that process this product. One of the most important of these devices is the mixer. First of all, it is an important task to create e...

A bstract We propose a new interacting dark sector model, Stepped Partially Acoustic Dark Matter (SPartAcous), that can simultaneously address the two most important tensions in current cosmological data, the H 0 and S 8 problems. As in the Partially Acoustic Dark Matter (PAcDM) scenario, this model features a subcomponent of dark matter that inter...

In this paper, we study the impulse controllability of a multi-dimensional heat equation with dynamic boundary conditions in a bounded smooth domain. Using a recent approach based on finite-time stabilization, we show that the system is impulse null controllable at any positive time via impulse controls supported in a nonempty open subset of the ph...

To advance the discussion of decarbonization, it is important to differentiate individual sectors because their inputs, operations, and externalities can differ significantly, and in some instances categorically. General discussions about decarbonization can lack precision when they center around or bias towards one solution that is inapplicable to...

Amid concerns over airflow-induced transmission of the COVID-19 virus in buildings frequented by large numbers of people, such as offices, the necessity for radiant ceiling heating panels has increased. This is due to the concern that the airflows emitted from the convection heating systems installed near the ceiling or windows for winter heating m...

One of the signatures of superconductivity is the formation of the Abrikosov vortex lattice in type-II superconductors in the presence of an external magnetic field. Here, we study the near-field radiative heat transfer between a spherical nanoparticle and a nearby planar substrate, both made of optimally-doped YBa$_2$Cu$_3$O$_{7-\delta}$. We show...

Heat exchangers (HXs) play a critical role in maintaining human thermal comfort and ensuring product safety and quality in various industries. However, the formation of frost on HX surfaces during cooling operations can significantly impact their performance and energy efficiency. Traditional defrosting methods primarily rely on time-based control...

When developing and researching management tasks, a climate model is needed. There are different ways to mathematically describe or predict parameters for controlling a greenhouse complex. Most authors represent the ambient air temperature by a Fourier series or its segment, as well as by trigonometric expressions. This approach makes it possible t...

The Newton´s cooling law still attracts the attention of scholars in order to describe hidden features of heat particles (thermons) and the mechanism of the radiating heat into the surroundings with a lower temperature. The characteristic cooling constant of this process 1/τπ [min-1] was defined as the experimental parameter describing the contribu...

Symmetrically designed fusion and heat concepts, space propulsion, and energy conversion issues with a particular interest in kinetic analysis, plasma power balance, advanced fuels, and alternative systems as new trends in experiments and theory, in physics, power engineering, and in very specific related areas such as space processes, cosmology, a...

While ball-milling is becoming one of the common tools used by synthetic chemists, an increasing number of studies highlight that it is possible to further expand the nature and number of products which can be synthesized, by heating the reaction media during mechanochemical reactions. Hence, developing set-ups enabling to combine heating and milli...

The deformation behavior of duplex stainless steel under tension and bending, accompanied by a pulsed current and when heated by an external source, is investigated. The stress–strain curves are compared at the same temperatures. The contribution to the decrease in flow stresses is greater when using a multi-pulse current at the same temperature, c...

This paper presents a detailed analysis of the research into modern thermal energy storage systems dedicated to autonomous buildings. The paper systematises the current state of knowledge concerning thermal energy storage systems and their use of either phase change materials or sorption systems; it notes their benefits, drawbacks, application opti...