Increase In Heat Flux Research Articles

Numerical study of turbulent flow boiling heat transfer in structured cooling channels using lattice Boltzmann method with advanced outlet boundary conditions

This study investigated the application of the lattice Boltzmann (LB) method to simulate turbulent flow boiling in structured cooling channels. The simulation used a central moment-based pseudopotential LB model with advanced characteristic boundary conditions to address numerical instabilities associated with turbulent multiphase flow. This approach ensures prolonged stability, facilitating the accurate modeling of complex flow boiling dynamics. The simulation results revealed that structured cooling channels considerably enhanced thermal performance, achieving a 27.3% increase in critical heat flux compared to flat channels. This improvement is induced by the fin structure of structured cooling channel, which makes heat distribution and promotes lower local wall heat flux compared with incident heat flux. Moreover, the simulations showed that fin structures manage bubble detachment more effectively, thereby enhancing heat transfer during the phase-change process. The study suggests that advanced outlet boundary conditions are crucial in stabilizing simulations for fin-structured channels, and the findings provide significant insights into heat dissipation mechanisms in high-heat-flux applications.

Fabrication and enhanced thermal performance of a self-rewetting wick of silicon-based loop heat pipe

The improvement of chip integration has led to increased heat flux, making heat dissipation in confined spaces increasingly challenging. Silicon-based loop heat pipes (sLHPs) offer a simple, reliable, and easily integrated thermal management solution. Still, problems like dry-out, limited heat exchange area, and flow instability hinder further heat transfer improvements of sLHP. Therefore, a novel composite MCC wick (Microchannel-micropillar Composite Cell arrays wick) incorporating microchannels into the micropillar arrays has been designed and experimentally studied in this work. The results indicate that micropillar arrays provide fluid flow freedom and a high heat exchange area, benefiting the efficient evaporation of the working fluid. The microchannels enhance fluid flow stability by providing continuous adhesion, promoting the directional supplement of working fluid. Moreover, liquid-replenishment microchannels have been introduced to the proposed MCC wick, enabling self-rewetting of the wick and enhance liquid film evaporation. The highest effective thermal conductivity of the sLHP reaches 856 W/(m·K) after structural optimization, which is significantly higher than that of other sLHPs. This work is expected to provide valuable insights for the optimal design of LHPs and chip heat dissipation.

THE INFLUENCE OF INCLINATION ANGLE ON THE HEAT TRANSFER CHARACTERISTICS OF MINIATURE TWO-PHASE THERMOSYPHONS WITH NANOFLUIDS

At present, the issue of modern heat-loaded electronic devices cooling is becoming increasingly relevant, given the clear trend towards miniaturization. A potential solution is the use of highly efficient cooling systems based on the evaporation-condensation cycle, with nanofluids serving as the heat carriers. These nanofluids are colloidal dispersions of nanoparticles in a base fluid (distilled water). Miniature thermosyphons (gravity heat pipes) can serve as the main element in such systems. This work presents and analyzes the experimentally obtained main heat transfer characteristics of miniature thermosyphons with nanofluids, namely: maximum heat fluxes that the system can transfer, and minimum total thermal resistance. During the development and design of the system, there is not always complete information regarding the scenarios of electronic device usage and their spatial arrangement, which can significantly influence the operation modes of the thermosyphons. Therefore, considerable attention in the work is paid to spatial arrangement (inclination angle relative to the horizontal level). The geometric parameters of the investigated thermosyphons were as follows: total length 700 mm, internal diameter 5 mm, and the filling ratio varied by changing the length of the heating zone in the range of 0.44–1.66. The condensation zone length for all experiments was 200 mm. Water-based nanofluids with added carbon black DG-100 nanoparticles (mass concentration 0.3 %) were used as the heat carrier. A similar miniature thermosyphon with deaerated distilled water as the heat carrier was used for comparison. Special attention was paid to determining the effect of adding nanoparticles to the base heat carrier and studying the influence of the filling coefficient and inclination angle on the heat transfer characteristics of the system. A significant influence of the filling ratio (length of the heating zone) on the heat transfer capacity of the system was observed. An increase in maximum heat fluxes of up to 21 % was recorded with the addition of nanoparticles to the heat carrier, while the total thermal resistance of the miniature thermosyphons remained at the same level (no deterioration was observed). The optimal range of inclination angles was determined to be 40–70°, with a critical angle at 30°, which is observed for water-based thermosyphons as well. A dependence was proposed to calculate the maximum heat flux that the system can transfer with a similar to the studied miniature thermosyphon for the angle range of 20–60°, assuming that heat transfer characteristics for vertical placement are known. Existing potential mechanisms for intensifying heat exchange processes in thermosyphons with nanofluids are analyzed. Bibl. 27, Fig. 10.

Influence of the density gradient on turbulent heat transport at ion-scales: an inter-machine study with the gyrokinetic code stella

Abstract Efficient control of turbulent heat transport is crucial for magnetic confinement fusion reactors. This work discusses the complex interplay between density gradients and microinstabilities, shedding light on their impact on turbulent heat transport in different fusion devices. In particular, the influence of density gradients on turbulent heat transport is investigated through an extensive inter-machine study, including various stellarators such as W7-X, LHD, TJ-II and NCSX, along with the Asdex Upgrade tokamak (AUG) and the tokamak geometry of the Cyclone Base Case (CBC). Linear and nonlinear simulations are performed employing the δf-gyrokinetic code stella across a wide range of parameters to explore the effects of density gradients, temperature gradients, and kinetic electrons. A strong reduction in ion heat flux with increasing density gradients is found in NCSX and W7-X due to the stabilization of temperature-gradient-driven modes without significantly destabilizing density-gradient-driven modes. In contrast, the tokamaks exhibit an increase in ion heat flux with density gradients. Notably, the behavior of ion heat fluxes in stellarators does not align with that of linear growth rates, if only the fastest-growing mode is taken into account. Additionally, this study provides physical insights into the microinstabilities, emphasizing the dominance of trapped-electron-modes (TEMs) in CBC, AUG, TJ-II, LHD and NCSX, while both the TEM and the passing-particle-driven universal instability contribute significantly in W7-X.

Evaluation of evaporative heat transfer performance based on observation of Thermo-Fluid behavior in porous structures fabricated by additive manufacturing

This study focuses on improving the performance of Loop Heat Pipes (LHPs) by investigating the thermo-fluid behavior within the evaporator. Previous observations using infrared and visible techniques have revealed potential improvement methods, such as modifications to vapor groove dimensions and enhancements in evaporator wettability. In this research, additive manufacturing technology is employed to manufacture both porous media and evaporator casings, with the aim of enhancing performance. The study evaluates four types of evaporator structures, including samples fabricated separately for porous media and heating plate corresponding to the evaporator casing, samples fabricated integrally, and samples with a porous monolayer loaded onto the heating plate. Micro-scale infrared observation is utilized to assess evaporative heat transfer coefficients and maximum heat flux. The experimental results demonstrate a substantial increase in maximum heat flux in structures where the porous body and heating plate are integrated into a single unit. Moreover, the investigation reveals the influence of the contact area structure between the porous media and heating plate on performance. The presence of voids in this area, allowing for improved vapor release during nucleate boiling, was found to enhance heat transfer efficiency. These findings underscore the efficacy of employing additive manufacturing technology for optimized evaporator designs, offering a pathway toward structurally enhanced and more efficient evaporators.

Numerical Study of Hydrothermal Enhancement of Two-Phase Flow in a Vertical Pipe by Using Modified Vortex Generators

The improvement in heat transfer and energy savings in two-phase (gas-liquid) flow in tubes occupies a wide area of research interest. In this work, the effect of modified twisted tape turbulators on heat transfer augmentation in vertical tubes is studied numerically by using the CFD technique. A vortex generator (twisted tape) was used as a passive method to raise the rate of heat transfer. The variants of the water flow rate, air flow rate, heat flux, and twisted ratio of a twisted tape tabulator were considered. This work provides a superficial water Re No. With ranges of 6300–10500, considering three different water and airflow rates. Additionally, the superficial gas Re range was 6000-16000. Three distinct twist ratios (TR) of 7.8, 3.9, and 2.6 were considered for the iron twisted tape to examine the impact of the twist ratio on the tube's thermo-hydraulic characteristics. The test section consisted of an insulated copper vertical tube subjected to three constant heat fluxes. This paper investigated three variants: the friction factor, Nusselt number, and performance evaluation factor. A strong turbulent vortex flow with an increase in secondary flow in the tube's radial direction was significantly intensified in the presence of the twisted tape inserted. Also, an increase in Reynold's number for both water and air and increased heat flux led to a proportional increase in heat transfer while the friction factor decreased. The presence of the modified twisted tape showed an improvement in the heat transfer and the pressure loss reduction when compared with the plain tape for all twisting ratios and for all cases where the highest value of the performance evaluation factor was two at the twisted ratio of 2.6 with an increase percentage of 81%. Conclusively, this investigation concludes that using modified twisted tape can greatly enhance the heat transfer rates and reduce pressure resistance, increasing the performance evaluation factor of heat exchanger systems.

Enhancing the solar still performance with nano-coated seashells and surface-modified absorber plates for clean water production

The study focuses on enhancing the thermal efficiency and water productivity yield of a double slope solar still (DSSS) by integrating a roughened corrugated copper plate, and nano-coated seashells. The surface-modified absorber plate, combined with small and larger-sized conch shells, intends to enhance thermal absorption, thermal transfer, and water evaporation. Four different SS are considered in this study, namely (i) CSS, (ii) corrugated absorber plate with shot blasting (CSBSS) (iii) corrugated absorber plate with small conch shell (CSBSSS), and (iv) corrugated absorber plate with big conch shell (CSBBSS) incorporated SS. The corrugation process and the conch shells’’ addition enhance the absorption, improving heat transfer, maintaining water temperature, reducing heat loss, promoting efficient water evaporation, and augmentation of durability and adaptability of the solar still system. The increased heat flux was observed in the corrugated copper plate (6400.7 W/m2), compared with the flat plate (4723.8 W/m2), suggests that the corrugated design is more capable of capturing and transmitting solar energy effectively through ANSYS software. The daily productivity of CSS was 1468 ml/m2/day, and CSBSS achieved 1708 ml/m2/day. Promoting the implementation of corrugation and the integration of conch shells, CSBBSS and CSBSSS systems exhibited improved yields, reaching 2002 and 2193 ml/m2/day, respectively. CSBSS, CSBSSS, and CSBBSS showed thermal efficiencies surpassing CSS by 6.41 %, 35.53 %, and 24.48 %, respectively. The average exergy efficiencies attained for CSS, CSBSS, CSBSSS, and CSBBSS were 1.653 %, 2.451 %, 3.91 %, and 3.29 %, respectively at an 8 % interest rate.

Heat propagation phenomenon of compressed natural gas /air premixed laminar flame impinging on a flat surface

In this paper the heat transfer characteristics have been determined theoretically using heat propagation phenomena of compressed natural gas (CNG)/air premixed laminar flames impinging on flat surfaces. Effects of varied equivalence ratios (Ф), Reynolds numbers (Re), separation distances (H/d) and burner diameters (d) on stagnation point heat flux have been investigated. The simulation findings were validated with the available experimental data. The flat plate with the maximum heat flux at the stagnation position is located close to the margin of the innermost premixed reaction zone (i.e., at H/d, Re and d are 5, 1000, 8 mm). The flow of heat steadily decreases in axial direction as the separating distance from the inner reaction zone's tip increases. Greater separation lengths at the stagnation region cause a subsequent increase in heat flux. The objective of this investigation is to get an idea about the impact of existence of the plate on the flame and temperature distribution and to get clarity about the reason behind higher amount of heat flux owing to tip of the innermost reaction area at stagnation region.

Experimental and numerical studies on enhanced flow boiling in tube with superwetting micro-finned surfaces

Due to the high latent heat from evaporation, flow boiling has been applied in a variety of industrial applications. However, the occurrence of “annular bubble” will dramatically increase the thermal resistance near the wall, causing decreases both in heat transfer coefficient (HTC) and critical heat flux (CHF). To tackle this issue, we propose the micro-finned surfaces with strong capillary force to enhance the heat transfer coefficient and critical heat flux for flow boiling. With deionized water as the coolant, we investigate the effects of fin width, fin height, fin pitch, coolant flow rate and heat flux on flow boiling through experiment and numerical simulation. The results show that the wider the fin width, the lower the fin height, and the smaller the fin pitch, the higher the convective heat transfer coefficient. In addition, the higher the coolant flow rate leads to higher heat transfer coefficient and lower flow boiling instability. When the heat flux increases, the convective heat transfer coefficient and flow instability increase. Among them, the microchannel with fin width of 20 μm, fin height 40 μm, and fin pitch 40 μm obtains the maximum convective heat transfer coefficient, 59.3 % higher than that of the smooth microchannel.

Experimental investigation on the influence of lubricant oil on CO2 nucleate pool boiling heat transfer characteristics

As a natural working fluid, CO2 is considered the most promising alternative refrigerant to hydrofluorocarbons. In the fields of automotive air conditioning and commercial heat pumps, transcritical CO2 cycles show significant potential for performance enhancement. Although there are many studies on CO2 flow boiling in the open literature, few studies involve CO2 nucleate boiling heat transfer, which is the dominant mechanism of CO2 flow boiling heat transfer process. This study is proposed to conduct experimental investigations of CO2 nucleate boiling heat transfer. The influences of evaporation temperature, heat flux and lubricant oil addition on boiling heat transfer performance and bubble dynamic characteristics are discussed. The results show that in pure CO2 nucleate boiling, heat flux increase leads to higher bubble density and bubble diameter in bulk liquid, which in turn enhances boiling heat transfer. The effect of evaporation temperature increases on bubble diameter is significant. The reduction in bubble diameter weakens the convective heat transfer caused by bubble motion, which leads to less variation in the CO2 nucleate boiling heat transfer coefficient with evaporation temperature. Lubricant oil addition significantly changes the bubble dynamics of CO2 nucleate boiling process, leading to larger bubble density and smaller bubble diameter. Moreover, the oil diffusion at the phase interface notably affects the heat transfer performance, resulting in greater differences in the boiling heat transfer characteristics of the mixtures compared to that of pure CO2. The mixture boiling heat transfer coefficient is collectively influenced by evaporation temperature, heat flux and oil concentration. The experimental results suggest that the heat transfer coefficient of the mixture with an oil concentration of 0.5 % increases by an average of 25 % compared to pure CO2 at an evaporation temperature of 0 °C. At higher evaporation temperatures and high oil concentrations (>1%), oil addition leads to heat transfer deterioration. Findings from this work can provide a better understanding of oil effect on refrigerant boiling heat transfer and a fundamental basis for heat exchanger design of CO2 systems.

Optimization of Thermal Management for the Environmental Worthiness Design of Aviation Equipment Using Phase Change Materials

A phase change materials (PCM)-based heat sink is an effective way to cool intermittent high-power electronic devices in aerospace applications such as airborne electronics and aircraft external carry. Optimizing the heat sink is significant in designing a compact and efficient system. This paper proposes an optimization procedure for the PCM/expanded graphite (EG)-based heat sink to minimize the temperature of the heat source. The numerical model is built to estimate the thermal response, and a surrogate model is fitted using the Kriging model. An optimization algorithm is constructed to predict the optimum parameters of the heat sink, and the effects of heat sink volume, heat flux, and working time on the optimal parameters of the heat sink are investigated. This shows that the numerical results agree well with the experimental data, and the proposed optimization method effectively obtains the optimal EG mass fraction and the geometric dimensions of the PCM enclosure. The optimal EG mass fraction increases with the rise in heat sink volume and decreases with the increase in heat flux and working time. The optimal ratio of the height to the length of the heat sink is 0.43. This study provides practical guidance for the optimal design of a PCM/EG-based heat sink.

Analysis of different laboratory-scale techniques for preventing coal spontaneous combustion

The focus of this study is to investigate laboratory-scale techniques aimed at preventing an increase in heat flux, which can potentially lead to spontaneous coal combustion. This research involves two pieces of equipment designed to analyze the heat flux on untreated coal and coal treated with polyvinyl alcohol (PVA). The laboratory equipment consists of a copper cell capable of holding up to 75 ml of coal samples and an aluminum cell designed to accommodate up to 3.17 ml of coal samples. The results on untreated coal showed that copper cell had a higher heat flux and took longer to reach the heat flux peak than aluminum cell. The aluminum cell provided more excellent stability, resulting in consistent heat distribution and dependable outcomes. The analysis using copper and aluminum cells on coal treated with PVA indicates that PVA can effectively reduce the heat of combustion by 35 %. This finding could have significant implications for future coal combustion studies. This study provides valuable insights for future research into coal spontaneous combustion experiments and using PVA to prevent spontaneous coal combustion.

Numerical Study of Complex Heat Transfer and Aerodynamics in a Tube Furnace with a Flat Fuel Combustion Mode

The object of the study is a tubular furnace for steam reforming of natural gas. The channel walls are formed by a refractory lining and a tubular screen with a known temperature. The chamber volume is filled with a selectively radiating, absorbing and weakly scattering medium of gaseous fuel combustion products. The research method is based on the numerical solution of a system of two-dimensional integro-differential equations of radiative gas dynamics, closed by a two-parameter model of turbulent convection. It is shown that when burners are located on the side walls of the radiation chamber, a significant restructuring of the heat flux distribution occurs. A decrease in the chamber width is accompanied by an increase in both radiant and convective heat fluxes to the tubular screen.

Numerical Study on Composite Multilayer Insulation Material for Liquid Hydrogen Storage

This study investigated the heat transfer characteristics of composite multilayer insulation (MLI) materials used for the storage and transport of liquid hydrogen at cryogenic temperatures. This research focused on analyzing the effects of thermal boundary temperature, total layer count, and vacuum level on the heat flux through the insulation material. Based on the layer-by-layer model, a heat transfer model of composite MLI was constructed. This research introduces a novel method for analyzing the heat transfer properties of composite MLI in the liquid hydrogen temperature range. Results indicate that heat flux increases with higher thermal boundary temperatures, with the MLI layers near the cold boundary playing a critical role in overall insulation performance. Additionally, numerical analysis was conducted to examine the impact of different material combinations and variations in vacuum level on heat transfer characteristics. Findings reveal that adding spray-on foam insulation reduces heat flux by 20.76% compared to using MLI alone. Furthermore, increasing the total number of MLI layers effectively mitigates heat flux increase, achieving an optimal heat flux of 0.5377 W/m2 with a total of 50 layers.

Flow behavior and heat transfer characteristics of liquid film on vertical hot surface by inclined jet impingement

In this study, the flow behavior and heat transfer characteristics of the liquid film on the hot wall by inclined jet impingement are experimentally studied in detail. The effects of jet parameters, such as jet inclination angle, impingement distance, jet Reynolds number (Rej), and nozzle diameter are explored. The liquid film flow is visualized using a high-speed camera, and the surface temperature and heat flux are obtained by solving the inverse heat conduction problem. The results indicate that the liquid film shape is strongly affected by jet inclination angle but is almost unaffected by other parameters. As the inclination angle increases, the liquid film shape changes from elliptical to fusiform. In addition, the onset, enhancement, and disappearance of boiling cause the expansion and contraction of liquid film. The splashing rate is barely affected by jet parameters and remains within the range of 80–95 % under all conditions. The propagation of wetting fronts exhibits anisotropy. Except for the impingement distance, the position of wetting fronts along y-axis direction displays a high dependence on all parameters. The Rej and nozzle diameter have a significant effect on the heat flux at the impingement point and parallel flow zone, while the jet inclination angle and impingement distance only effect the impingement point. The visualization image proves that the droplet impingement pattern is the main reason for the increase in heat flux at higher impingement distances. Optimizing jet parameters can promote the wall to enter the rapid cooling stage in advance and increase maximum heat flux, thereby improving the maximum cooling capacity of the jet. Finally, an empirical equation is proposed to predict the maximum Nusselt number.

Experimental study of flow boiling heat transfer in rectangular ribbed micro-channels with rectangular cavities

The flow boiling heat transfer in the RRM (i.e. ribbed micro-channel with aligned side-wall rectangular cavities), ORM (i.e. ribbed micro-channel with offset side-wall rectangular cavities), and ORMB (i.e. ribbed micro-channel with offset side-wall and bottom rectangular cavities) were experimentally investigated at a range of heat fluxes and mass fluxes. Combined with the visualization technology, the influences of offset rectangular cavities on the heat transfer and pressure drop penalty were revealed. The results showed that the existence of offset rectangular cavities enhances the heat transfer performance of micro-channels in both single-phase and two-phase regions. The bottom rectangular cavities in the ORMB enhances the disturbance to the main stream, thus further enhancing the heat transfer performance in the single-phase region and shifting from laminar to transitional flow earlier compared to the ORM. The capillary effect provided by the bottom cavities intensifies the heat transfer in the two-phase region, resulting in a significant increase in the critical heat flux in the ORMB. Compared to the ORM, the maximum increase of critical heat flux in the ORMB reaches 22.3 % (17.57 W·cm−2). The existence of offset rectangular cavities causes alternating resistance forces to the main stream, which increases the pressure drop in the ORM by 8–32.2 % compared to the RRM. The capillary effect provided by the bottom cavities to the liquid-phase in the ORMB is beneficial for the alleviation of vapor blockage and expansion. Hence the pressure drop in the ORMB is reduced by 82.3 % at most compared to the ORM in the two-phase region.

Effects of the urban development on the near-surface air temperature and surface energy balance: The case study of Madrid from 1970 to 2020

The aim of the present study is to examine the impact of Madrid's urban growth over the last 50 years (1970–2020). We conduct a modelling study using WRF-ARW with the multilayer urban parameterization BEP-BEM, in which different urban parameters have been incorporated at each point within the model's inner domain according to urban expansion from 1970 to 2020. Two scenarios of important societal interest with different meteorological conditions are selected for this study: a period of intense heatwave during the summer season and a short period of strongly stable atmospheric conditions in winter, both in 2020. The results show that in areas where the urban fraction becomes greater an increase in near-surface air temperature is found for both simulated periods, especially during the night. The urbanization modifies the surface energy balance and turbulent transport in Madrid and its surroundings. It leads to a decrease in latent heat flux due to the high impermeability and reduced vegetation in urban areas. Additionally, the urban areas with a higher density of buildings have a high heat capacity, increasing heat flux storage during the day through solar radiation absorption. This stored energy is released at night, exacerbating the increase in nighttime near-surface air temperature in both periods.

Additively-manufactured shear tri-coaxial rocket injector mixing and combustion characteristics

A monolithic tri-coaxial propellant injection scheme for enhanced mixing of methane-oxygen in liquid-propellant rocket systems is enabled by additive manufacturing. Mixing and combustion characteristics of the tri-coaxial design are assessed experimentally from 1–69 bar using laser absorption tomography and chemiluminescence imaging, and are compared to a traditionally-manufactured bi-coaxial design. Quantitative two-dimensional images of temperature and carbon monoxide mole fraction are generated from the laser absorption spectroscopy methods, while OH* chemiluminescence provides an approximate metric for combustion heat release defining flame length and injector standoff distance. At similar pressures and oxidizer-to-fuel ratios, the tri-coaxial injector design is shown to enhance mixing and combustion progress, reducing characteristic mixing length scales and achieving improved combustion performance relative to more conventional bi-coaxial designs. Despite enhanced mixing, the tri-coaxial design exhibits more limited reduction in flame standoff distance from the injector face, suggesting that increased heat flux to the injector face can be managed. The tri-coaxial injector highlights the potential to leverage additive manufacturing to enhance performance and simplify the fabrication of liquid-propellant rocket engines.

Development and Optimization of a Micro-Baffle for the Enhancement of Heat Transfer in Film Boiling

This study represents the development and optimization of a micro-baffle design to enhance heat transfer in film boiling. Numerical simulations are performed using an open-source computational fluid dynamics (CFD) model, which incorporates the Lee model for momentum source associated with the phase change, and the Volume of Fluid (VOF) method to capture bubble dynamics. A comparison of the numerical results with the previous numerical and experimental data confirmed the validity of the numerical model. The influence of key design parameters was systematically investigated. The results revealed that a vertical baffle provided the maximum performance. The optimal baffle design achieved a 57.4% improvement in the Nusselt number and a 66.4% increase in critical heat flux (CHF). Furthermore, the proposed design facilitated continuous bubble formation, even with a reduced temperature difference between the heated surface and the subcooled liquid, which is crucial for energy-efficient thermal management in engineering systems. Ultimately, this study demonstrates the potential of micro-baffle designs in controlling bubble dynamics and improving heat transfer in film boiling, thereby aiding the design of efficient thermal systems.

Thermal Performance Investigation of Vapor Chamber Under Partial Heating and Different Heat Flux Conditions: Effects of Inclination Angle

Abstract The need for cooling technologies increases tremendously with raising demand on the powerful and compact electronics. There, it pushes the research and technology to the new investigations on varying heat transfer mechanisms and devices. While one of these devices is vapor chamber (VC), an experimental study has been carried out to investigate the heat transfer performance of a VC under partial heating, varying heat fluxes, and different inclination angles for different temperatures, in the current study. For this purpose, a VC with a dimension of 90 mm × 90 mm × 3 mm is evaluated via its resulting thermal resistance, performance, and the temperature distribution over the VC surface. There, the limited effect of inclination angle is observed on the performance, while the highest change is obtained with decreasing local heating surface area, thus increasing heat fluxes. Moreover, this trend is seen almost similar with a reasonable shift up or down according to the different temperature differences.