Boiling Heat Transfer Characteristics Research Articles

Enhanced pool boiling heat transfer characteristics on microstructured copper surfaces coated with hybrid nanofluid

Enhanced pool boiling heat transfer characteristics on microstructured copper surfaces coated with hybrid nanofluid

Enhancement of flow boiling heat transfer characteristics on diamond/Cu heterogeneous surface

Surface treatment is an effective method of enhancing the heat transfer performance of flow boiling. Nonetheless, the majority of existing studies on surface treatment primarily concentrated on homogeneous materials and their associated zone design. Diamond/Cu, as a particle‐reinforced composite, exhibits heterogeneous surface properties and surface microstructures that play distinct roles in the heat transfer. To elucidate the synergistic effect of heterogeneous material surfaces and microstructures, pure copper surface (PC), untreated diamond/Cu surface (DC), and surface‐treated diamond/Cu surface (SDC) were prepared for this experiment. These surfaces demonstrate various combinations of diamond, copper, and their corresponding surface microstructures. DC, characterized by heterogeneous wetting properties, demonstrates a heat transfer coefficient that is 9%–24% higher than that of PC. No trend of decreased heat transfer capacity is observed in DC. The surface treatment of SDC results in the formation of a superhydrophilic CuO nanosheet structure, significantly enhancing both surface roughness and energy. SDC develops microcracks on the surface of diamond. The increased roughness provides numerous nucleation area for the hydrophobic diamond, enhancing the overall wettability of the surface when combined with the superhydrophilic CuO region. SDC demonstrates the advantage of enhanced flow boiling on the surface of heterogeneous materials. At the identical heat flux, SDC exhibits a reduction of 5 °C–10 °C in wall superheat and an increase of 38%–47% in heat transfer coefficient.This article is protected by copyright. All rights reserved.

Experimental investigation on the boiling heat transfer characteristic of copper surfaces with different hydrophilicity

Surface hydrophilicity has a significant effect on boiling heat transfer. In order to systematically investigate the influence of hydrophilic degree on the boiling heat transfer performance, seven different surfaces with gradually changing contact angles (CAs) were prepared using the chemical etching technology. Meanwhile, Visual studies on pool boiling of four of these different hydrophilic surfaces were conducted using a high-speed camera at atmospheric pressure, with deionized water as the working fluid. The influence laws of the hydrophilicity coefficient and relative wall superheat on the enhancement of boiling heat transfer are systematically summarized. It is shown that the boiling heat transfer coefficient (HTC) and critical heat flux (CHF) of the heating surface increased as the CA decreased. Owing to its vertically and horizontally interlaced nanorods and nanoflower structures, the surface oxidized by NaOH/(NH4)2S2O8 has higher surface roughness and larger phase change heat transfer area, resulting in a super-hydrophilic property of the copper surface and a faster bubble detachment frequency. The CHF and boiling HTC were 1.16 and 1.59 times that of the untreated surface, respectively, and the onset of nucleate boiling was advanced by 3.1 K, greatly enhancing boiling heat transfer and exhibiting better heat transfer performance.

Experimental study of boiling heat transfer characteristics of multi-elbow cooling system under one-sided heating with long section for fusion divertor cooling

In this study, heat transfer experiments were conducted under one-sided heating conditions using water as the coolant and an electron gun as the heat source. To evaluate the boiling heat transfer characteristics of the swirling flow formed by a multi-elbow piping, heat flux by the electron gun is deposited on the region of 60 mm-section in the flow direction corresponding to 0.5 D (inner diameter of the flow channel) to 6.5 D from the elbow outlet, and then temperature distributions in the flow, circumferential and radial directions were measured. The experimental results showed that the wall temperature cooled by the swirling flow generated downstream of the multi-elbow was lower than that obtained in the case of turbulent flow in the straight pipe when irradiated with the same value of heat flux. Thereby, the heat fluxes at the boiling start and DNB points obtained in the multi-elbow case were higher than those in the straight pipe case. These results imply the superior cooling performance of multi-elbow system.

Experimental study on heat transfer characteristics of dispersed flow during strong transient reflood process

The dispersed heat transfer correlations obtained in the quasi-steady-state heating experiment may have some limitations in the strong transient reflood process. Therefore, this article will conduct a visualization experiment on single-rod channel reflood cooling under different working conditions. By combining the transient hydrodynamic characteristics of liquid droplets and the wall temperature transient curve, the boiling heat transfer characteristics of the dispersed flow stage during the reflood process are studied. Through comparative analysis, this article found that the traditional post-CHF (Critical Heat Flux) heat transfer correlations are difficult to characterize the impact of droplet number and size changes. This article is based on the form of a divided path heat transfer mechanism model. In response to the strong transient characteristics of dispersed flow during the reflood process in a restricted channel, the single-phase steam heat transfer model and the steam-droplet interfacial heat transfer model have been modified, greatly improving the prediction accuracy. The RMS of the predicted heat transfer coefficient decreased from 0.68 in the original model to 0.24 in the new model.

An experimental study on flow boiling heat transfer in porous-ribbed micro-channels

Experiments were carried out to investigate flow boiling heat transfer characteristics in a micro-channel heat sink with porous ribs at three rib-heights (i.e. Hrib = 200 μm, 400 μm, and 600 μm), three mass fluxes (i. e. 200 kg/m2s, 300 kg/m2s, and 400 kg/m2s), and a range of wall heat fluxes (30–1300 kW/m2). The heat transfer coefficients and temperature uniformity in porous-ribbed micro-channels under different conditions were analyzed and compared to the smooth micro-channels (i.e. smooth flat surface and smooth-ribbed surfaces). The flow regimes in both porous and smooth micro-channels were visualized under typical flow boiling conditions. The results showed that micro-channels with higher rib heights experience an earlier transition to the critical heat flux (CHF) region due to the narrower flow path. Compared to the smooth micro-channel, the configuration of porous coating significantly enhances the heat transfer in the micro-channel without ribs or with lower rib height (Hrib = 200 μm) due to the strong hydrophilicity, good liquid storage, and rewetting ability on porous surfaces. At G = 400 kg/m2s, the porous-flat surface achieves a 67.9 % enhancement of heat transfer coefficient in the micro-channel compared to the smooth-flat micro-channel. However, with a higher rib height (Hrib = 400 μm and 600 μm), the thermal resistance is increased which hinders the heat conduction along the rib-height direction. A significant superheat is observed at the bottom of porous surface, thereby deteriorating the heat transfer performance in the porous ribbed micro-channel.

Flow Boiling Heat Transfer Characteristics and Delayed Dry-Out Ability of Non-Azeotropic Mixtures R245fa/R134a in Microchannels

Flow Boiling Heat Transfer Characteristics and Delayed Dry-Out Ability of Non-Azeotropic Mixtures R245fa/R134a in Microchannels

Corrosive effect on saturated pool boiling heat transfer characteristics of metallic surfaces with hierarchical micro/nano structures

Surface modification is of critical interest to enhance boiling heat transfer in terms of heat transfer coefficient or critical heat flux (CHF), which is significantly affected by distinct surface morphology and wettability and it can improve the efficiency and safety of equipment. Furthermore, actual service environment may cause severe corrosion to the processed structured surfaces while its consequence on boiling heat transfer is still obscure. In this article, comprehensive researches are conducted to unravel corrosive effect on metallic samples made of stainless steel (SS) and Inconel materials with microstructures. Different constructions (i.e., microgroove, microcavity and micropillar array) and characteristic dimensions (∼20, 50 μm) of microstructure, various duration time (up to 300 days) and pH values (∼7.0–8.5) of corrosive environment are compared thoroughly. Conclusions can be drawn that not all microstructures can enhance pool boiling heat transfer characteristics, especially in terms of CHF values. More importantly, CHF value of SS microgroove sample firstly increases from 60.94 to 94.09 W·cm−2 in 50 days, then decreases to 47.77 W·cm−2 in 300 days, which can be attributed to competition result between formation of hierarchical micro/nano structure with enhancing wicking capability and chemistry condition with increasing contact angle. In addition, distinct bubble dynamics during pool boiling is also analyzed. The insights obtained from this article can be used to guide surface modification method and to reveal evolvement rule of engineered metallic surface in highly corrosive and harsh boiling heating transfer environment.

Flow boiling heat transfer of R1234ze(E) in a horizontal mini-channel at medium and high saturation temperatures

This study reports experimental results of flow boiling heat transfer characteristics of R1234ze(E) (a low global warming potential refrigerant) at moderate and high saturation temperatures. The study was performed in a single horizontal circular smooth tube of 2.07 mm internal diameter. Heat transfer characteristics and flow pattern visualization through high-speed camera were investigated for saturation temperatures ranging from 60 to 95 °C, corresponding to reduced pressures from 0.35 to 0.75, mass velocities from 300 to 500 kg/m2s, heat fluxes from 30 to 50 kW/m2 and vapor qualities from 0 to 1. The pre-dryout data (214 data points) measured were compared against different prediction methods from the literature developed under different theories. The study revealed that the saturation temperature has a significant effect on heat transfer coefficient whereas the mass velocity presented a less pronounced or negligible effect. Furthermore, the heat transfer coefficient was observed to decrease slightly to a minimum in the low vapor quality region and then levels off or increases slightly with increasing vapor quality until dryout occurs. As a result, nucleate boiling was observed to be the dominant mechanism controlling the heat transfer. It was observed that the higher the saturation temperature, the earlier the vapor quality at which dryout incipience occurs. Considering the 214 pre-dryout data points analyzed, the methods proposed by Kew and Cornwell (1997), Lazarek and Black (1982) and Choi et al. (2007) were the most accurate, predicting the entire pre-dryout database with mean absolute errors (MAEs) of 13.7%, 13.9 % and 14.4 %, respectively.

Enhancing boiling heat transfer by high-frequency pulsating jet with piezoelectric micropump

Two-phase jet impingement provides a compact cooling solution capable of dissipating high heat flux at a low pressure drop, making it favorable for electronic cooling. However, there is still a limited understanding of the boiling characteristics of high-frequency pulsating jets. To address this knowledge gap, experiments are conducted using a piezoelectric micropump to study the boiling heat transfer characteristics. The frequency of the pulsating jet was controlled by adjusting the applied signal of the piezoelectric micropump, ranging from 10 Hz to 40 Hz. Both steady jet boiling and pulsating jet boiling were investigated using two nozzle configurations, with the flow rate varying from 30 to 120 ml/min. It is found that the high-frequency pulsating jet can significantly improve the critical heat flux (CHF) to 245.2 W/cm2 at the flow rate of 60 ml/min, 84% higher than that of the steady jet. But the high-frequency pulsating jet shows no markable effects on the heat transfer coefficient within the studied parameters. This research also discussed the mechanism behind the CHF enhancement, which provides valuable insight into jet impingement boiling under flow pulsation. Furthermore, the proposed two-phase cooling system is suitable for high-power-density electronics owing to its compactness and high thermal performance.

Numerical investigation on boiling crisis in a full-length 5 × 5 fuel assembly under typical pressurized water reactor conditions

Critical heat flux (CHF) presents a research priority in the Pressurized Water Reactor (PWR) safety, as it can lead to the severe accidents and release radioactive materials. In this study, a wall heat flux partition model, proposed by Demarly [1], was employed within the two-fluid model by Computational Fluid Dynamics (CFD) methodology to investigate the characteristics of CHF under typical PWR conditions. A multi-scale interface model was coupled to consider the interfacial transfers in bulk flow during flow regime transition. The models were validated by using experimental data on subcooled flow boiling, boiling crisis in vertical tubes, and rod bundles. The PWR sub-channel and bundle test (PSBT) benchmark, comprising a full-length 5 × 5 fuel assembly with three different types of spacers, was simulated in this study. The CHF value was evaluated, demonstrating an acceptable accuracy compared to the experimental data, with a deviation of less than 10 % in the selected conditions. The CHF location in the cross section was successfully predicted by CFD approach, while the axial location of CHF was underestimated than experimental measurement. Besides, the impacts of mixing vanes with different deflection angles on boiling heat transfer characteristics were analyzed, revealing the crucial role of mixing vanes in the distribution of vapor and dry-patch area fraction in both the circumferential and flow directions.

Boiling heat transfer characteristics of self-rewetting fluid based on the bi-porous sintered surface

Enhancing boiling heat transfer by changing the working fluid or surface modification is an effective and simple method. In order to investigate the effect of the coupling characteristics of porous sintered surfaces with self-rewetting fluid, pool boiling experiments were carried out on the polished copper surface (PCS) and the bi-porous sintered surface (BPS) with n-heptanol aqueous solution as the working fluid. The experimental results showed that, for the PCS cases, the self-rewetting fluid enhanced the heat transfer coefficient (HTC), while reduced the critical heat flux (CHF). This is because while self-rewetting fluid promoted the generation and detachment of bubbles, it also caused gas–liquid conflict, resulting in the surface was covered by a layer of vapor film. As for the boiling experiments on the BPS, the self-rewetting fluid not only enhanced the HTC but also enhanced the CHF. The Marangoni effect, generated by the self-rewetting fluid, replenished the BPS and coupled with its stronger capillary force. That led to surface wetting and reduced conflict between gas and liquid flow. Consequently, under this coupling effect, the heat transfer coefficient (HTC) of 0.1 wt% n-heptanol aqueous solution was 178.7 % higher than that of deionized water with PCS.

Flow boiling heat transfer characteristics and correlation development of R290/R600a mixtures in an internally threaded tube

Excessive hydrofluorocarbons (HFCs) usage significantly contributes to the global warming. Therefore, there is a widespread shift toward natural refrigerants with low global warming potential (GWP). Among these alternative refrigerants, R290, R600a, and their mixtures have gained considerable attention. However, their flammability limits the charge. To decrease the equipment volume and reduce the refrigerant charge, internally threaded tubes have been introduced to enhance the heat transfer. Therefore, in this study, flow boiling experiments were conducted on R290, R600a, and mixtures inside an internally threaded tube, obtaining heat transfer data under a pressure of 0.216–0.416 MPa, heat flux of 10.5–73.0 kW m−2, mass flux of 70–190 kg m−2 s−1. To quantitatively discern the dominant heat transfer mechanism, a dimensionless number Nz was introduced. In the nucleate boiling dominant region, an increase in the heat flux markedly enhances the heat transfer, with pressure and mass flux playing minor roles. Furthermore, the heat transfer deterioration trend of the mixtures aligns with the variation trends of concentration slip and boiling range. In the convective heat transfer dominant region, a rise in the mass flux significantly increases the heat transfer coefficient, while the pressure and heat flux have minor effects. Additionally, at high R290 mole fraction and vapor quality, high surface tension maintains a continuous liquid film, enhancing the heat transfer. Furthermore, new heat transfer correlations for flow boiling inside the internally threaded tubes were established, which exhibit a mean relative deviation of −2.30 % and 8.80 % for the obtained experimental results and collected data, respectively.

Investigation of Heat Transfer Performance in Deionized Water–Ethylene Glycol Binary Mixtures during Nucleate Pool Boiling

Pool boiling heat transfer is recognized as an exceptionally effective method, widely applied across various industries. The adoption of non-azeotropic binary mixtures aligns with the environmental objectives of modern industrial development and enhances the coefficient of performance (COP) in numerous systems. Therefore, investigating the boiling heat transfer characteristics of these mixtures is crucial to improving their industrial usability. In this study, mixtures of ethylene glycol and deionized water (EG/DW) in varying concentrations were chosen as the working fluids. A comprehensive experimental setup was developed, followed by a series of experiments to assess their pool boiling performance. Simultaneously, the thermophysical parameters of these mixtures underwent detailed examination and analysis. The research revealed that the concentration of EG in the mixture markedly affects its thermal properties and temperature glide, both of which are crucial in influencing the heat transfer coefficient. Additionally, six established heat transfer coefficient prediction correlations, primarily designed for pure fluids, have been employed. However, their application to non-azeotropic mixtures under experimental conditions revealed significant deviations. To address this issue, the present study modified existing correlations with the temperature slip characteristics of non-azeotropic mixtures. This process involved recalibrating the wall superheat values in the correlations to reflect the local temperature differential at the boiling point, thereby customizing them for application to non-azeotropic mixtures. The modified correlations highlighted the unique behaviors of non-azeotropic mixtures in boiling heat transfer, demonstrating improved compatibility with these mixtures in a deviation within a permissible 20% range compared with experimental results.

Study on boiling heat transfer characteristics of R410A outside horizontal tube under swaying condition

To investigate the boiling characteristics of flow outside the R410A tube under swaying conditions, this article conducts numerical simulation and experimental research on the flow boiling heat transfer of R410A outside a horizontal tube. The results show that when the swing frequency increased from 0.2 to 2 Hz, the sway amplitude is 0.03 m, the heat flux on the inner wall of the runner remains unchanged, and the mass flow rate increases from 85 to 170 kg/(m2·s), which makes the heat transfer coefficient of the working fluid in the annular area increases significantly. Keeping the inlet mass flow rate unchanged, the heat flux on the inner wall of the flow channel increases from 25 to 35 kW/m2, the heat transfer coefficient of the working fluid in the annular area has also improved, but under high heat flux conditions, the working fluid is evaporated and dried, its heat transfer coefficient increases less than in low heat flux conditions. When the sway amplitude increases from 0.02 to 0.07 m, the sway frequency is 0.2 Hz and 2 Hz respectively, and the heat transfer coefficient of the working fluid shows a downward trend as a whole. The studies provide a reference for heat exchanger design suitable for offshore swaying conditions.

Surface heat flux of upward circular water jet impingement on a moving hot steel sheet

This study experimentally investigated the boiling heat transfer characteristics of a circular upward water jet issued from a 7-mm-diameter nozzle impinging on a moving hot 0.3- mm-thick stainless-steel sheet. The moving velocity (1.5, 3.0, and 4.4 m/s), temperature (100–590 °C), and water flow rates (2.5, 3.0, and 3.5 L/min) were varied during the test. The surface heat flux in the jet impact region depended significantly on the initial temperature of the solid. The surface heat flux increases as the solid temperature increases, attains a peak value (∼30 MW/m2) before decreasing, and reaches a valley value before increasing again. Furthermore, the moving velocity of the solid influences the cooling characteristics, considering that the duration of water contact of a local point on the test sheet is shorter for larger velocities. Moreover, the maximum value of the surface heat flux in the jet impact region can be roughly correlated with the local temperature of the solid. The maximum heat flux peaked at approximately 190 °C and reached a valley at approximately 370 °C. Three empirical correlations for predicting the maximum heat flux in the nucleate, transition, and film boiling are built as functions of the local temperature. The equations in the transition and film boiling can predict the results within a ±20 % error margin.

Improved flow boiling performance and temperature uniformity in counter-flow interconnected microchannel heat sink

Microchannel flow boiling is one of the most effective solutions to the problem of heat dissipation caused by high power electronic devices. However, inherent drawbacks such as low critical heat flux due to dry-out of the liquid film near the channel exit, relatively high two-phase flow pressure drop, severe temperature nonuniformity and boiling instability at high heat flux still prevent widespread commercial application. In this study, based on the idea of uniform vapor quality along the flow direction, a copper Counter-Flow Interconnected Microchannel (CFIM) was proposed to address the main issues currently faced by two-phase microchannel heat sink. A comprehensive comparative study of CFIM, Co-Current Microchannel (CCM) and Counter-Flow Microchannel (CFM) was carried out from the aspects of boiling stability, boiling heat transfer characteristics and temperature uniformity. Three slots of 0.2 mm, 0.5 mm and 0.8 mm in width, denoted as IM0.2, IM0.5 and IM0.8, respectively, are considered. Experiments are conducted at mass fluxes of 291–618 kg/m2·s, saturation temperature of 40 °C and effective heat fluxes of 3–293 W/cm2, using the dielectric fluid R1233zd(E) as the working fluid. The results show that the CHF and average two-phase heat transfer coefficient (HTC) of CFIM are increased by 40.6 ∼ 100.5 % and 70.4–83.6 %, respectively, while the two-phase pressure drop is decreased by 17–32.6 % compared to CCM. The design of the counter-flow interconnected structure can manipulate the void fraction and two-phase flow pattern, resulting in a near uniform void fraction and flow pattern. The structure of these connecting slots promotes nucleate boiling and fluid mixing of neighboring channels. More importantly, the flow boiling instability and temperature non-uniformity in CFIM are well suppressed. In addition, IM0.2 has higher heat dissipation than IM0.5 and IM0.8 due to enhanced bubble nucleation, reducing superheat requirements and periodic rewetting to the center of the channel. The results of this research reveal that utilizing a microchannel heat sink with a counter-flow interconnected configuration can effectively improve heat transfer performance during flow boiling. Furthermore, it helps to mitigate issues such as flow boiling instability and temperature non-uniformity.

POOL BOILING HEAT TRANSFER CHARACTERISTICS OF POROUS NICKEL MICROSTRUCTURE SURFACES

Pool boiling is an effective heat dissipation approach in electronic cooling, battery thermal management, etc. This study used the electrochemical deposition method to fabricate one smooth nickel specimen (named Ni-smooth) and three specimens with a porous nickel-stacked structure. The three porous specimens were created with deposition current densities of 0.5 A·cm<sup>-2</sup> (named Ni-0.5), 2.0 A·cm<sup>-2</sup> (names Ni-2.0), and 5.0 A·cm<sup>-2</sup> (named Ni-5.0), respectively. The four samples underwent microstructural characterization via scanning electron microscopy. The increasing current density led to the porous nickel surface exhibiting a more distinct pore structure, and the nickel sphere grains became more refined, developing a loose "mound-like" structure. A marked increase in the nickel film thickness was also observed. Through visual experiments, we evaluated their wettability, and through pool-boiling experiments, we tested their boiling heat-transfer properties. Our findings suggest that samples incorporating a porous nickel structure consistently outperform unmodified samples regarding heat-transfer efficiency. Specifically, sample Ni-0.5A demonstrated the most optimal boiling heat-transfer performance, evidenced by a 32.2% reduction in temperature at the onset of boiling, a 19.9% increase in critical heat flux density, and a 78.6% larger maximum heat-transfer coefficient compared to the smooth nickel sample. These marked improvements are intrinsically linked to the specific characteristics of the porous nickel structure. The higher performance of samples Ni-0.5 can be attributed to the presence of additional nucleation sites within the porous structure and the formation of smaller micro-crystalline dendritic constructs due to the specific current density applied during electrodeposition. Understanding this relationship between surface characteristics and electrodeposition is essential in maximizing heat-transfer efficiency.

Numerical analysis of reflood heat transfer and large-break LOCA including CRUD layer thermal effects

This study examined the effects of CRUD on reflood heat transfer behaviors of nuclear fuel rods during a loss-of-coolant-accident (LOCA) in a pressurized water reactor using a best-estimate thermal-hydraulic analysis code. Changes in thermal properties and boiling heat transfer characteristics of the CRUD layer were extensively reviewed, and a set of correction factors to reflect the changes was implemented into the code. A heat structure layer reflecting the effects of CRUDs on the properties was added to the outer surface of the fuel cladding. Numerical simulations were conducted to examine the effects of CRUDs on reflood cooling of overheated fuel rods for representative separate and integral effect tests, FLECHT-SEASET and LOFT. In LOFT analysis, the average cladding temperature was increased due to the low thermal conductivity of CRUD during steady-state operation; however, in both analyses, the peak cladding temperature decreased, and the quenching time was reduced. Obtained results revealed that when the porous CRUD layer is deposited on the fuel cladding, two opposite effects appear. Low thermal conductivity of the CRUD layer always increases fuel temperature during normal operation; however, its hydrophilic porous structures may contribute to accelerated reflood cooling of fuel rods during a LOCA.

Experimental study on flow boiling of HFE-7100 in rectangular parallel microchannel

With the rapid development of microelectronic technology, the integration and power of chip are increasing. Heat dissipation with high heat flux in limited space has become a bottleneck restricting the efficient and stable operation of the microelectronic devices. Flow boiling in microchannel heat sink is one of the most essential candidates for solving this problem. It has been shown that remarkable high heat transfer performance can be achieved through the liquid-to-vapor change process, which can dissipate a large amount of heat from a small area. In addition, dielectric fluorinated fluids, such as HFE-7100, HFE-7200, and FC-72, are especially suitable for cooling microelectronic devices, because of their excellent safety and environmental characteristics. However, dielectric fluorinated fluids have poorer thermophysical properties than water. Thus, the flow boiling heat transfer characteristics of dielectric fluorinated fluids can be different from those of water. In this work, flow boiling heat transfer and flow characteristics of HFE-7100 in a rectangular parallel microchannel are investigated. The tests are conducted at mass fluxes from 88.9 to 277.8 kg·m<sup>–2</sup>·s<sup>–1</sup>, inlet subcooling temperature from 20.5 to 35.5 ℃ and effective heat flux from 12 to 279 kW·m<sup>–2</sup> at nearly atmospheric pressure. The effects of mass flux, inlet subcooling temperature, effective heat flux and vapor quality are examined and analyzed. Additionally, flow visualization is also obtained to explain the heat transfer mechanism during the experiments. The results show that the boiling hysteresis is observed for HFE-7100 at low inlet subcooling temperature, and the increasing inlet subcooling temperature and mass flux can delay the onset of nucleate boiling. The increases of inlet subcooling temperature and mass flux can enhance the two-phase heat transfer coefficient. And the two-phase heat transfer coefficient is significantly dependent on the inlet subcooling temperature in the slug flow, while it is significantly dependent on the mass flux in the annular flow. The two-phase pressure drop increases drastically as the effective heat flux increases. And the two-phase pressure drops with different mass fluxes at constant vapor quality are obviously different between the slug flow and the annular flow. Furthermore, the experimental data are compared with four predicted values of the literature. It is found that the correlation of Lockhart has the best statistical agreement with an MAE of 19.6% and over 85% of points in the deviation bandwidth of ±30%. The results in this paper give valuable theoretical guidance for designing and optimizing heat dissipation equipment for microelectronic devices. By utilizing HFE-7100 as the coolant and microchannel heat sinks in flow boiling, it is possible to enhance the stability and reliability of the electronic devices. Additionally, the heat transfer performance associated with different heat fluxes can be improved by regulating the inlet subcooling and mass flow rate. Finally, the two-phase pressure drop correlation proposed by Lockhart can be employed to predict the pump power for heat dissipation equipment.