Heat Flux Rate Research Articles

Impact of induced magnetic field on Darcy–Forchheimer nanofluid flows comprising carbon nanotubes with homogeneous-heterogeneous reactions

The appealing traits of carbon nanotubes (CNTs) encompassing mechanical and chemical steadiness, exceptional electrical and thermal conductivities, lightweight, and physiochemical reliability make them desired materials in engineering gadgets. Considering such stimulating characteristics of carbon nanotubes, our goal in the current study is to scrutinize the comparative analysis of Darcy–Forchheimer nanofluid flows containing CNTs of both types of multi and single-wall carbon nanotubes (MWCNTs, SWCNTs) immersed into two different base fluids over a stretched surface. The originality of the model being presented is the implementation of the induced magnetic field that triggers the electric conductivity of carbon nanotubes. Moreover, the envisioned model is also analyzed with homogeneous-heterogeneous (h-h) chemical reactions and heat source/sink. The second-order slip constraint is assumed at the boundary of the surface. The transmuted high-nonlinearity ordinary differential equations (ODEs) are attained from the governing set of equations via similarity transformations. The bvp4c scheme is engaged to get the numerical results. The influence of different parameters is depicted via graphs. For both CNTs, the rate of heat flux and the surface drag coefficient are calculated using tables. It is highlighted that an increase in liquid velocity is witnessed for a varied counts volume fraction of nanoparticles. Also, Single-wall water-based carbon nanotube fluid has comparatively stronger effects on concentration than the multi-walled carbon nanotubes in water-based liquid. The analysis also indicates that the rate of heat flux and the surface drag coefficient are augmented for both SWCNTs and MWCNTs for different physical parameters. The said model is also validated by comparing it with a published result.

The impact of equivalence ratio on the fire characteristics of Kerosene/air flame produced by NexGen burner for aeronautic application

This paper provides an experimental investigation of a Kerosene/air flame (produced by the NexGen burner designed by the FAA, and here calibrated for ISO 2685/AC20-135 standards fire tests conditions), which is used to generate flame/burnt gases impinging on material samples in the field of fire safety. The purpose of this study is to characterize this burner, and experimental means are implemented to better understand the effects of the equivalence ratio on the spatial distribution of the gas temperature (thermocouples) and the heat flux (heat flux gauge). A parametric study was carried out by varying the global equivalence ratio (ER); highlighting a flickering phenomenon, a relation between the ER and the heat flux, and determining empirical correlations. Hence, the measured flame temperature, heat flux, and heat release rate increase up to a critical value of equivalence ratio equal to 1.03 (flame temperature (1101.5 °C) and heat flux (140 kW/m2).

Minimum entropy generation paths for generalized radiative heat transfer processes with heat leakage

Heat transfer processes (HTPes) with generalized radiative heat transfer law (HTL) [q∝Δ(Tn)] and heat leakage (HL) are optimized. With net amount of heat transferred (NAHT) of working fluid at low-temperature side and given process period, optimal path, that is, optimal temperature configuration of reservoir (TCR), for entropy generation minimization (EGM) of HTP is derived. Universal result for optimal path is provided, and results for four special HTLs, that is, Newtonian, radiative, linear phenomenological, and mixed HTLs, are further provided. Optimal path with EGM is compared with traditional ones of constant heat flux rate (CHFR) and constant reservoir temperature (CRT). Effects of HL and NAHT on optimal results are analyzed. Results show that ratio of heat flux rates between reservoir and working fluid to (n1+1)/2 power of reservoir temperature for EGM of HTPes without HL is a constant, but the optimal relationship between temperatures of working fluid and reservoir with HL is significant different. The differences among TCRs with different heat transfer paths increase with increases of HL and NAHT. The path of CHFR is very close to that of EGM, and the two paths are superior to that of CRT.

A PARAMETRIC STUDY ON THE THERMAL HOMOGENEITY OF VAPOR CHAMBER IN A BATTERY COOLING SYSTEM

For the battery cooling system, the large temperature difference of the coolant between the inlet and outlet leads to a decrease in the thermal homogeneity of batteries. To improve the thermal homogeneity, a designed composite liquid cooling system was analyzed combined with a grooved vapor chamber and a cooling plate. The parametric study on the thermal homogeneity was conducted including the height, width, length of grooved wick, filling ratio, flow rate of coolant, heat flux, and inclination angle. The results show that a preferable thermal homogeneity can be obtained at 20% filling ratio as the height and width of the channel increase, especially under the positive inclination angle of 20°. The heat source surface can be kept uniform within the temperature difference of 5°C in spite of the temperature rise of coolant up to 11.5°C under the flowing rate of 8.32 × 10<sup>-4</sup> kg/s. An empirical correlation of the "suppression ratio," containing the structural and operating parameters, is summarized to evaluate the suppressing function of the vapor chamber on the temperature difference of coolant. This research is aimed to provide a scientific basis for predicting the thermal homogeneity of the vapor chamber in a battery liquid cooling system.

Recent Advances in Computational Convective Heat Transfer Study in a Sub-Channel for Nuclear Power Reactor and Future Directions

A nuclear power reactor's primary use is to generate thermal energy, which in turn produces electricity. The primary heat source is a nuclear fission event occurring inside the fuel rod. The convection heat is transmitted through the coolant by the heat energy generated at the fuel rod wall boundary. Better heat transfer is produced in the flow area by turbulence and irregularity. As a result, turbulent flow heat transfer may present a significant challenge when predicting and assessing the thermal performance of nuclear power reactors. Computational techniques in convective heat transfer have become indispensable for solving challenging issues in the fields of science and engineering thanks to the development of current sophisticated numerical methods and high-performance computer hardware. The development of novel computational techniques and models for complicated transport and multi-physical phenomena is constantly in demand throughout applicable disciplines. This chapter's objective is to provide some recent developments in computational techniques for convective heat transfer, taking into account research interests in the community of mass and heat transfer, and to showcase relevant applications in nuclear power plant engineering domains including future directions. This study describes the most recent advancements in nuclear reactor convective heat transfer research utilizing the computational fluid dynamics (CFD) method, particularly at Ansys Fluent. This work examines the convective heat transfer and fluid dynamics fluid dynamics for turbulent flows across three rod bundle sub-channels that are typical of those employed in the PWR-based VVER type reactor. In this paper, CFD analysis is carried out using the software tool Ansys Fluent. Temperature distribution profile, velocity profile, pressure drop, and turbulence properties were investigated in this study. Boundary conditions i.e. temperature, velocity, pressure, heat flux, and heat generation rate were applied in the sub-channel domain. The main obstacles and bright spots for the CFD methods in nuclear reactor engineering are discussed, which helps to further its further uses. We intend to research a full-length fuel bundle model for VVER-1200 in the future to gather specific fluid characteristic data and use the findings to analyze safety and operate nuclear power facilities in Bangladesh. This paper presents a thorough analysis of the sub-channel thermal hydraulic codes used in nuclear reactor core analysis. This review discusses several facets of previous experimental, analytical, and computational work on rod bundles and identifies potential future directions based on those earlier studies.

Heat flux and flame spread rate of discrete PMMA in concave building facade with window intervals

Heat flux and flame spread rate of discrete PMMA in concave building facade with window intervals

Experimental and Numerical Study of the Trench Fire Spread Rule over a Sloped Uniform Fuel Bed: Rate of Fire Spread, Flame Morphology, and Heat Flux

Trench fires on sloped terrain are always complicated due to the corresponding flame dynamics and heat transfer mechanisms. Flame attachment may increase the rate of fire spread (ROS) by enlarging the heating area of unburned vegetation. In addition, variations in radiative and convective heat flux are of great importance to fire behavior characteristics. In this work, trench fire tests under different slopes (θ) and inclined sidewalls (A) were performed by numerical simulations based on the Lagrangian Particle Model (LPM) and Boundary Fuel Model (BFM) in the Fire Dynamics Simulator (FDS) and small-scale experiments, and the ROS, flame characteristics, and radiative/convective heat flux of the fire front are discussed in detail. The results indicate that the flame tends to adhere to the fuel bed with increasing slope angle and sidewall inclination. In particular, the flame becomes fully attached with a greater pressure difference than the buoyancy, which is caused by the unequal air entrainment between the front and behind the flame. When A = 90°, the critical slope angle of the flame adhesion (from slight tilt to full attachment) is identified as ~20°. The ROS (θ ≤ 15°) predicted by the BFM and LPM are closer to the small-scale experiments. The heat fluxes based on the experiments confirm the predominant mechanism of radiative heat transfer in trench fires at low slopes (θ ≤ 20°). Furthermore, convective heat transfer is more significant than radiative and becomes the main heating mechanism for θ ≥ 20°.

Study of Influences of the Level of Zr Oxidation and Volumetric Heat Generation on Heat Transfer and Crust Formation Within CANDU Corium

A full-station blackout at a nuclear power plant can lead to fuel failures and radiological release to the environment if there is a breach of the reactor vessel. For Canada Deuterium Uranium (CANDU) reactors, the expected failure mechanism is through thermal stress concentration at the calandria vessel wall, and is thus influenced by local heat flux values. The current study uses computational fluid dynamics to simulate heat transfer, fluid flow, and crust formation within a CANDU geometry. Sensitivity to critical parameters, including the volumetric decay heat generation rate and the percentage of Zr oxidation is explored. The results show that as the volumetric heat generation rate decreases, the crust is thicker, and the wall heat flux is lower. This suggests that the activation of mitigating measures that delay the accident progression result in more favorable outcomes. The percentage of Zr oxidation primarily influences the thermal conductivity, which impacts the crust formation and wall heat flux rates. Specifically, corium with a lower percentage of Zr oxidation has higher thermal conductivity, and thus lower heat transfer resistance. This results in lower corium temperatures, which reduces the radiation heat transfer from the top surface and also increases crust thickness. Higher rates of heat removal from the vessel wall thus occur. In contrast, a higher percentage of Zr oxidation results in lower thermal conductivity, which leads to lower wall heat flux and a thinner crust at the vessel wall. Overall, these findings highlight the importance of considering the effects of sensitivity parameters on the heat flux distribution in the event of severe accidents.

Entropy generation analysis on Darcy-Forchheimer Maxwell nanofluid flow past a porous stretching sheet with threshold Non-Fourier heat flux model and Joule heating

This research paper inspects the flow characteristics of a magnetohydrodynamic (MHD) Maxwell nanofluid in the presence of a Darcy-Forchheimer (DF) model applied to a stretching sheet. Additionally, numerical analysis is performed to evaluate the findings, utilizing a nanofluid composed of copper (Cu) suspended in water. The energy equation in this study incorporates thermal radiation, viscous dissipation, the Cattaneo-Christov heat flux model, and joule heating. The entropy generation is then determined based on the obtained solutions for temperature and velocity, in compliance with the flow constraints. By applying suitable similarity transformations, the conservative equations of energy and momentum are transformed into nonlinear ordinary differential equations (ODEs). To solve these equations, a bvp4c method implemented through Matlab software is employed. By taking into account pertinent characteristics like the relaxation Prandtl number, magnetic parameter, time parameter, radiation parameter, and others, one can analyse the normalized shear stress at the wall, temperature profile, and rate of heat flux. For practical purposes, the local Nusselt and number of skin frictions are determined for various modified values of the physical constraints. This provides vital insights about the system's behavior under various settings. The graphical results indicate that the velocity profile exhibits a decrease as the volume fraction, magnetic parameter, Maxwell fluid parameter, and inertia coefficient parameter increase. The entropy generation demonstrates an increase with growing values of the Brinkman number and magnetic parameter. On the other hand, entropy generation declines with increasing values of the temperature ratio parameter. The Bejan number exhibits the opposite behavior of the entropy generation. Specifically, as the Bejan number increases, the entropy generation decreases, and vice versa.

Investigation of Z-type manifold microchannel cooling for ultra-high heat flux dissipation in power electronic devices

Ultra-high heat flux (up to 1000 W/cm2) thermal management has been an urgent need for advanced power electronic devices to maintain their superior electrical performance and reliability. Embedded microchannel cooling is a promising and challenging thermal management method for high-heat-flux chips. This study presents an embedded Z-type manifold microchannel (Z-MMC) cooling design for a 5 × 5 mm2 heating zone, which can dissipate an ultra-high heat flux up to 1842 W/cm2 by using water single-phase flow. The microchannel array is etched on silicon wafer, while the manifold structure is fabricated by PDMS molding. The test chips are assembled using O2 plasma bonding technique, which provides an observation window for visualizing the flowing state of the coolant during the heat transfer process. We experimentally test and compare four test chips with different microchannel geometries and manifold designs. The average heater temperature, temperature distribution, thermal resistance, heat transfer coefficient and pressure drop are reported for mass flow rates of 2–6 g/s. The proposed Z-MMC cooler is capable of dissipating up to 1800 W/cm2 with a total thermal resistance of only 0.075 cm2·K/W (only 0.039 cm2·K/W after subtracting the conduction thermal resistance), at a flow rate of 6 g/s and a pressure drop of 54 kPa. Compared to the rectangular manifold arrangement, the trapezoidal manifold demonstrates a lower temperature rise, a more uniform temperature distribution and a smaller pressure drop at the same heat flux and flow rate, mainly due to a more uniform fluid distribution in the microchannel. Furthermore, we compare our proposed design's thermo-hydraulic performance with those of representative manifold microchannel cooling data in the literature, and the proposed Z-MMC design demonstrates relatively low thermal resistance and pressure drop values.

Investigation of the flame properties and fire behavior of carbon‐reinforced PEKK, BMI and phenolic composites impacted by Jet‐A1/air flames

AbstractThis paper provides an experimental investigation of a kerosene/air burner (the NexGen burner designed on the FAA's proposed ISO 2685 standard), which is used to generate flame/burnt gases impinging on material samples in the field of fire safety. The purpose of this study is to characterize this burner, and experimental means are implemented to better understand the effects of the equivalence ratio on the spatial distribution of the gas temperature (thermocouples), the heat flux (heat flux gauge), and gas emission species. Hence, the measured flame temperature, heat flux, and heat release rate increase up to a critical value of equivalence ratio equal to 1.03. Furthermore, a pyrolysis test was carried out on composite materials and the results of the comparative analysis of carbon‐phenolic, carbon‐BMI, and carbon‐PEKK materials show that carbon‐PEKK had the lowest mass loss, highest back‐face temperature without significant material delamination, and the lowest concentration of gas emission species.

Mathematical modeling of viscoelastic fluid flow across a nonlinear stretching surface in porous media with varying magnetic field

We investigate the cross-diffusion on MHD mixed convective thermo-solutal transport in viscoelastic fluid from a nonlinear stretching sheet. The novelty of the work is the analytical evaluation of the nonlinear stretching sheet in a porous medium with a variable magnetic parameter and radiative flux. Also, thermo-solutal transport of a mixed convective flow is analyzed with Dufour and Soret effects in the presence of the chemical reaction, heat source/sink. The governing PDEs are reduced into ODEs by similarity variables. ODEs were tackled analytically using the homotopy analysis method (HAM). The analysis is carried out up to the 15th order of approximation. HAM contains an h-curve, allowing a flexible method of controlling the series solution convergence area. Graphs and tables are plotted to analyze the influence of different parameters on the fluid. Rates of heat and mass flux are depicted using tables. Our results indicate that the increasing viscoelastic flow enhances the boundary layer, and the thermal boundary layer reduces as radiation enhances. The numerical demonstrations of the wall drag coefficient, Nusselt number and Sherwood number have been tabulated. The growing parameters are taken as [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text]

Experimental monitoring of CO2 hydrate slurry crystallization by heat flux rate determination in a jacketed reactor

CO2 hydrate slurries are promising phase change materials for secondary refrigeration applications. However, the difficulty of experimentally evaluating the crystallization kinetic of slurries limits their industrial use. Hydrate crystallization kinetics monitoring performs traditionally by a reactor mass balance. However, this method requires assumptions on CO2 liquid phase concentration and the hydration number. This work outlines the development of a specific method to determine kinetics thanks to the direct measure of heat flow through the reactor jacket and its evaluation compared with the mass balance method. The results of each method are then obtained by testing the two kinetic parameters of stirring speed and propeller type. The final hydrate mass fractions obtained with both methods are in good agreement, but the kinetic obtained by the mass balance method is faster than by the heat balance method.

A new analytical model of condensation outside low-finned tubes for refrigerants at low temperatures and high heat flux

In this paper, a new analytical model is developed for the condensation of refrigerants outside low-finned tubes. It is based on the flow and heat transfer characteristics at low saturation temperatures and high heat flux, such as those in the LNG intermediate fluid vaporizer (IFV). Due to the increase of viscous effect at lower saturation temperature and higher heat flux, the previous condensate retention angle models are modified by adding the viscous term. At high heat flux and condensate rate, the condensate profile at the fin root is simplified to be arc-shaped and obtained directly by force analysis. Furthermore, considering the heat transfer enhancement caused by the circumferential flow at high heat flux, the convective mechanism is included for the heat transfer through the thick liquid film between the fins. The distributions of liquid film and fin surface temperature are also predicted. The present analytical model is in good agreement with different experimental and numerical results, while most deviations are within 10% for predicting the heat transfer coefficients at high heat flux. Because of the increased flow viscosity and surface tension, the optimal fin spacing and fin height increase as the heat flux increases and the saturation temperature decreases.

A molecular-kinetic theory based model for alkali liquid metal boiling incipience analysis

Boiling can lead to unexpected heat transfer performance of the components using alkali liquid metal (ALM) as working fluid for high thermal conductivity. Thus study on incipient boiling superheat of ALM is important to the design and safety operation of related components. However, existing data are in large scatter and some important parameter trends are inconsistent, indicating that more research should be done to understand the basic mechanism of ALM boiling incipience. In this paper, the local heat transfer of a wall cavity was investigated and the molecule performance at the three-phase contact line (TPL) was analyzed with molecular-kinetic theory. It was found that during transient process, the liquid temperature distribution near the interface in the cavity may result in considerable unbalanced molecule displacement at TPL and change the contact angle significantly. By estimating the evaporation rate at TPL with interface deformation rate and local temperature gradient, a model which could correlate nucleation contact angle as well as nucleation superheat with heat flux, velocity and interface deformation rate was established. The model was then used to predict the nucleation superheat data involving effects of temperature ramp, heat flux and velocity, and good agreement was gained. Besides, the characteristics of nucleation superheat of different heating methods were also analyzed and the trend of velocity effect was discussed, and some phenomena observed in different experiments were explained.

Design and analysis of cooling jacket developed for vacuum power tubes by multiphase cooling

The vacuum tubes are used extensively in electronic industries. The MW level of vacuum tube are used in RF amplifiers and microwave sources in different sectors like defence, nuclear energy, satellites and medical diagnostics. The first step in the indigenous development of MW level of vacuum tube is the design of its cooling jacket. The cooling jacket of vacuum tubes use hypervapotron (HV) fins which are known for providing efficient cooling in compact space. The key objectives of this paper are to finalize the jacket’s construction material, evaluate the cooling jacket’s heat transfer performance at the MW level of RF (radiofrequency) power, and forecast safe operating conditions for given conditions of high heat flux and water flow rates. In this design, the vacuum tubes’ external dimensions are taken into consideration when designing the cooling jacket. ETP copper (Electrolytic Tough Pitch copper) and copper-chromium-zirconium (CuCrZr) are likely materials for the jacket’s construction. For the aforementioned design of the cooling jacket, FEA (Finite Element Analysis) simulations using a steady-state thermal module and computational fluid dynamics (CFD) simulations using an ANSYS CFX module are described for flow rates of 15, 30, and 60 lpm (liters per minute) and the heat flux 1, 2, 4, and 6 MW m−2. The results of CFD and FEA simulations are found to be in close agreement. A small deviation in results is seen after the start of nucleate boiling. 30 and 60 lpm are desirable flow rates for high heat flux values greater than 2 MW m−2. CuCrZr is the ideal material for a cooling jacket’s construction as it has safe working temperature limit of 350 °C at high heat flux values. Also, 15 lpm flow rate should be avoided while using this cooling jacket at heat flux values greater than or equal to 6 MW m−2.

Falkner-Skan aspects of a radiating (50% ethylene glycol + 50% water)-based hybrid nanofluid when Joule heating as well as Darcy-Forchheimer and Lorentz forces affect significantly

Falkner-Skan aspects are revealed numerically for a non-homogeneous hybrid mixture of 50% ethylene glycol-50% water, silver nanomaterials Ag, and molybdenum disulfide nanoparticles MoS2 during its motion over a static wedge surface in a Darcy-Forchheimer porous medium by employing the modified Buongiorno model. The Brownian and thermophoresis mechanisms are included implicitly along with the thermophysical properties of each phase via the mixture theory and some efficient phenomenological laws. The present simulation also accounts for the impacts of nonlinear radiative heat flux, magnetic forces, and Joule heating. Technically, the generalized differential quadrature method and Newton-Raphson technique are applied successfully for solving the resulting nonlinear boundary layer equations. In a limiting case, the obtained findings are validated accurately with the existing literature outcomes. The behaviors of velocity, temperature, and nanoparticles volume fraction are discussed comprehensively against various governing parameters. As crucial results, it is revealed that the temperature is enhanced due to magnetic field, linear porosity, radiative heat flux, Brownian motion, thermophoresis, and Joule heating effects. Also, it is depicted that the hybrid nanoliquids present a higher heat flux rate than the monotype nanoliquids and liquids cases. Moreover, the surface frictional impact is minimized via the linear porosity factor. Furthermore, the surface heat transfer rate receives a prominent improvement due to the radiative heat flux inclusion.

Effects of vortex generator on subcooled flow boiling characteristics in micro-channel

Subcooled flow boiling in a micro-channel is a mainstream heat dissipation way for high-heat-flux electronics. This paper presents a new idea to enhance heat transfer of subcooled flow boiling, i.e. accelerating bubble departure from the heating wall of flow channel by inserting a vortex generator; and the effects of vortex generator positions and working fluid conditions on the heat transfer characteristics are experimentally studied. The shape of the vortex generator is helix with the length, pitch, helix diameter and wire diameter of 22.5 mm, 1.8 mm, 1.8 mm and 0.2 mm, respectively. The vortex generator positions in the experiments include the front, the middle and the end of the flow channel; and the working fluid conditions include the mass fluxes of 1000 – 3500 kg m−2 s−1 and the inlet subcooling degrees of 30–50 K. It is found that the vortex generator could accelerate the bubble departure from the wall, and thus enhance the heat transfer in subcooled flow boiling. The maximum increase of the heat transfer coefficient of the all vortex channel is 8.4 × 103 W m−2 s−1, and the maximum increase rate of critical heat flux (CHF) is 21.8%. Furthermore, a new correlation to predict the heat transfer coefficients of vortex enhanced subcooled flow boiling was developed. The predictions by the new correlation could agree with 92% of the experimental data within a deviation of ± 30%, and the average deviation is 13.7%.

Vapor condensation heat transfer on two-tier hierarchical microstructured surface

Condensation heat transfer on the hierarchical microstructured surfaces is simulated using a three-dimensional phase-change lattice Boltzmann method. Parametric effects raised by widely varying primary micropillar spacing, secondary micropillar position and height, surface wettability and subcooling on the condensation heat transfer are discussed in detail. The condensation heat flux first increases but then decreases with the increase of spacing between primary micropillars. Droplets are prone to nucleate on the top sides of primary micropillars with smaller pillar spacing, and they tend to maintain the Cassie‐Baxter state when secondary micropillars are arranged on the lateral sides of primary micropillars. As the height of secondary micropillar increases, the heat flux first increases but then decreases thereafter. When the contact angle rises from 57° to 130°, the state of condensate droplet changes from the Wenzel state to the partial wetting state. It is also found that there exist four types of droplet nucleation sites on the hierarchical microstructured surface: at the bottom of secondary micropillars, at the corner between primary micropillars and substrate, between two adjacent primary micropillars, and at the center of substrate between four primary micropillars. The increase of subcooling is favorable for nucleation, and the heat flux and condensation rate increase in accordance.

A novel advanced absorption heat pump (Type III) for cooling and heating using low-grade waste heat

The heat of low-grade can be used to get cooling and heating simultaneously by using the coupling of two absorption heat pumps (conventional/not conventional). This novel advanced absorption heat pump requires three pressure levels to increase and reduce the temperature of useful heat, where desorption/condensation processes are shared at medium pressure, and the two evaporation/absorption processes are developed at low and high pressure respectively. The aim of this proposal is to study this kind of advanced absorption heat pump (Type III) by using the first and second laws of thermodynamics, to determine the energy and exergy coefficient of performances for the whole system by taking into account three scenarios of heat flux rates for both evaporators. The irreversibility and exergy performances for the main components are determined to improve the exergy coefficient of performance. The understanding of reversible Carnot cycles, and the general relationship of energy coefficient of performances at low, medium, and high temperatures for this proposal are analyzed. This advanced absorption heat pump reaches cooling temperatures from 14 to 20 °C and heating temperatures between 80 and 106 °C using water/lithium bromide as a working solution. The energy coefficient of performance of 0.68 is obtained when the higher thermal load of the cooling evaporator than the heating evaporator.