This study quantifies the potential of a 4.0 kW air source heat pump (ASHP) unit retrofitted to a 12.0 kW, 1000 L electric boiler coupled to a 1000 L storage tank. A data acquisition system was built to monitor the performance of the electric boiler...
Optimization problems relating to heat source operation are solved via linear (LP) or nonlinear (NLP) programming. The optimization methods used can be compared based on the complexity of the computational program setup, the time required to input an...
This paper presents a novel methodology for estimating space- and time-dependent source terms in heat and mass diffusion problems. The approach combines classical integral transform techniques (CITTs) with the least squares optimization method, enabl...
This article provides plain and handy expressions to decide the most suitable analytical model for the thermal analysis of the ground source in vertical ground-coupled heat pump applications. We perform a comprehensive dimensionless analysis of the r...
The article studies the simulation-based mathematical modeling of bioheat transfer under the Dirichlet boundary condition. We used complex non-linear dual-phase-lag bioheat transfer (DPLBHT) for analyzing the temperature distribution in skin tissues...
Double diffusive convection in a binary viscoelastic fluid saturated porous layer in the presence of a cross diffusion effect and an internal heat source is studied analytically using linear and nonlinear stability analysis. The linear stability theo...
In order to predict long-term changes in the temperature of the ground in which a horizontal ground heat exchanger has been installed, it is beneficial to implement simplified mathematical models of heat transfer. The possibility of using a one-dimen...
Estimating the thermo-elasto-plastic deformation by arc welding through finite element analysis has been used in various industrial fields. The Goldak heat source model is one of the most important and widely used models in finite element analysis, a...
Multi-energy systems (MESs) combining different energy carriers like electricity and heat allow for more efficient and sustainable energy solutions. However, optimizing the design and operation of MESs is challenging due to non-linearities in the mat...
The erosion and sedimentation of bank slopes are important factors affecting the safety of wharf operations. The essence of bank slope monitoring is to identify the water–soil interface. This paper proposes a model for soil-and-water interface...
Multi-energy systems can integrate heat and electrical energy efficiently, using resources such as cogeneration. In order to meet energy demand cost-effectively in a multi-energy system, adopting appropriate energy resources at the right time is of g...
Linear stability analysis of a steady convective flow in a tall vertical annulus caused by nonlinear heat sources is conducted in the paper. Heat sources are generated as a result of a chemical reaction. The effect of radial cross-flow through permea...
The main goal of the current research is to investigate the numerical computation of
The coordinated use of electricity and a heat energy system can effectively improve the energy structure during winter heating in the northern part of China and improve the environmental pollution problem. In this paper, an economic scheduling model...
When a sample of semiconducting material is illuminated by monochromatic light, in which the photon energy is higher than the energy gap of the semiconductor, part of the absorbed electromagnetic energy is spent on the generation of pairs of quasi-fr...
The behavior of the Darcy–Forchheimer flow of a double-hybrid nanofluid toward a Riga plate with radiation and heat source/sink effects is investigated. The two different hybrid nanofluids, (Al
This work develops the analysis of power quality by the H-bridge Static Distribution Compensator (DSTATCOM) as well as its control techniques in different industry-based loading conditions. The function of DSTATCOM is to diminish power quality proble...
To achieve the ambitious targets of net-zero greenhouse gas emissions by 2050, there is a need for change in all parts of society, industry, and mobility, as well as in all energy sectors. For this purpose, sector coupling plays a crucial role, e.g.,...
El Niño is generally associated with negative rainfall anomalies (below-average rainfall) in northern Northeast Brazil (NNEB). In 2019, however, the opposite rainfall pattern was observed during an El Niño episode. Here, we explore the...
The efficiency of a heat pump energy system is significantly influenced by its low-temperature heat source. This paper presents the results of operational monitoring, analysis and comparison of heat transfer fluid temperatures, outputs and extracted...
The paper deals with an analysis of temperatures of ground masses in the proximities of linear and slinky-type HGHE (horizontal ground heat exchanger). It evaluates and compares the potentials of HGHEs and ambient air. The reason and aim of the verif...
Based on a model of a two-heat-reservoir heat engine with a finite high-temperature source and bypass heat leak, the optimal configuration of the cycle is found for the fixed cycle period with another linear heat transfer law . The finite thermal cap...
Tunnel portal rocks in southern China, which are exposed to intense solar radiation and temperature fluctuations, are susceptible to thermal stress, which directly or indirectly affects the safety, stability, and normal use of a tunnel and its periph...
The erosion of the seabed around offshore structures has emerged as a critical factor impeding the operational safety of offshore engineering facilities. Prompt and precise identification and monitoring of the water–soil interface hold signific...
In recent years, the shipbuilding industry has experienced a growing demand for tighter control and higher strength requirements in thick steel plate welding. Electro-gas welding (EGW) is a high heat input welding method, widely used to improve the w...
The objective of this work was to monitor and analyse temperature changes in the ground with installed linear and Slinky-type horizontal ground heat exchangers (HGHEs), used as low-potential heat pump energy sources. Specific heat flows and specific...
The closed-form solution, one of the effective and sufficient optimization methods, is usually less computationally burdensome than iterative and nonlinear minimization in optimization problems of heat source localization. This work presents two-dime...
The Double Diaphragm Preforming (DDPF) process uses vacuum pressure and heat to pre-shape dry carbon fabric reinforcements between flexible diaphragms in liquid composite molding (LCM). Accurate modeling of heat transfer within DDPF requires knowledg...
The dynamics of non-Newtonian Jeffrey fluid in conjunction with a spinning disk surface can be problematic in heating systems, polymer technology, microelectronics, advanced technology, and substantive disciplines. Therefore, the significance of the...
From the point of view of finite time thermodynamics, the performance boundaries of thermal machines are considered, taking into account the irreversibility of the heat exchange processes of the working fluid with hot and cold sources. We show how th...
The mixed convection and heat transfer in enclosures with inner heat sources widely exist in building ventilation, cooling of nuclear reactors and cooling of electronic components. In this study, the heat transfer characteristics of mixed convection...
The aim of this work is an experimental evaluation of a specific heat capacity as a function of plastic strain for thermo-mechanically rolled pipe material, with application of an infrared thermographic camera. The tensile load tests of samples prepa...
This paper solves the inverse source problem of heat conduction in which the source term only varies with time. The application of the discrete regularization method, a kind of effective radial symmetry and axisymmetric heat conduction problem source...
The aim of this paper is to conduct a generalised assessment of both optimal working fluids and radial turbine designs for small-scale organic Rankine cycle (ORC) systems across a range of heat-source temperatures. The former has been achieved by cou...
Several studies have involved a combination of heat and gravitational energy exchanges to create novel heat engines. A common theoretical framework is developed here to describe thermogravitational cycles which have the same efficiencies as the Carno...
The aim of this scientific research is to experimentally determine the exergy losses of a ground heat pump and further optimization for more efficient use of operating modes and improvement of individual structural elements. In addition, it is propos...
Linear plasma devices have been increasingly applied in investigating plasma–surface interaction (PSI) processes and divertor/scraped-off-layer (D/SOL) physics because of their economy, flexibility, and expandability. However, only a few existi...
Ground source heat pump (GSHP) systems depend on the capacity for heat transfer between the system and the ground, and it is good practice to carry out an in situ thermal response test (TRT) to determine the undisturbed ground temperature, the therma...
Laser powder bed fusion (LPBF) is widely used in metal additive manufacturing to create geometrically complex parts, where heat transfer and its affected temperature distribution significantly influence the parts’ materials’ microstructur...
Heat flow sensors allow the straightforward measurement of the heat flow emitted from an object by attaching the sensor to the object. However, the inability of this method to control the surface emissivity of the sensor over a wide range lowers the...
In Poland, domestic hot water is heated mainly using fossil fuel energy sources. Such an approach results in the depletion of natural resources, pollution of the atmosphere and, consequently, irreversible changes to the climate. In response to this p...
The ground-heating method using the electric heating pipe improves many problems of the conventional soft-ground improvement method and the ground-heating method using fossil fuel. However, in order to use this method practically, it is necessary to...
Specialized Gaussian process regression is presented for data that are known to fulfill a given linear differential equation with vanishing or localized sources. The method allows estimation of system parameters as well as strength and location of po...
Based on the finite element method, the modulation of the bending wave bandgap and bending waveguide of locally resonant phononic crystal (PnC) plates via a thermal environment is investigated. First, the finite element model of the PnC subjected to...
In recent decades, the approach known as Finite-Dimension Thermodynamics has provided a fruitful theoretical framework for the optimization of heat engines operating between a heat source (at temperature Ths) and a heat sink (at temperature Tcs). We...
The long-term trend and interannual variation of ocean heat content (OHC) in the Bohai Sea, Yellow Sea, and East China Sea (BYECS) were examined using 27 years (1993–2019) of daily reanalysis data from the Japan Coastal Ocean Predictability Exp...
Several optimization models of irreversible reverse cycle machines have been developed based on different optimization criteria in the literature, most of them using linear heat transfer laws at the source and sink. This raises the issue how close to...
Ticks use chemical and thermal signals emitted by humans and other vertebrates to locate suitable hosts for a blood meal. Here, we study the behavior of black-legged Ixodes scapularis and the lone star ticks Amblyomma americanum exposed to heat sourc...
Due to the growing demand for new ecological, low-emission heat sources, there is a need to develop new tools for simulating the operating parameters and costs of the implemented solutions. The article analyses the existing solutions for the simulati...
Taking into consideration the inaccurate temperature predictions in traditional thermal models of power devices, we undertook a study on the temperature rise characteristics of heterojunction bipolar transistors (HBTs) with a two-dimensional cross-se...
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