Fluid In Channel Research Articles

DEM-CFD Simulation Analysis of Heat Transfer Characteristics for Hydrogen Flow in Randomly Packed Beds

In this study, three randomly packed beds with varying tube-to-particle diameter ratios (D/d) are constructed using the discrete element method (DEM) and simulated via CFD under low pore Reynolds numbers (Rep < 100). An innovation of this research lies in the application of hydrogen in randomly packed beds, coupled with the consideration of its temperature-dependent thermal properties. The axial analysis of the heat transfer characteristics shows that PB−5 and PB−6 achieve thermal equilibrium 44% and 58% faster than PB−4, respectively, demonstrating enhanced heat transfer efficiency. However, at higher flow rates (0.8 m/s), the large-sized fluid channels in PB−6 severely impact the heat transfer efficiency, slightly reducing it compared to PB−5. Additionally, this study introduces a localized segmentation method for calculating the axial local Nusselt number, showing that the axial local Nusselt number (Nu) not only exhibits an inverse relationship with the axial porosity distribution, but also matches its amplitude fluctuations. The wall effect significantly impacts the flow and temperature distribution in the packed bed, causing notable velocity and temperature oscillations in the near-wall region. In the near-wall region, the average temperature is lower than in the core region, and the axial temperature profile exhibits more intense oscillations. These findings may provide insights into the use of hydrogen in randomly packed beds, which are vital for enhancing industrial applications such as hydrogen storage and utilization.

Coupled Detachment Faulting and Hydrothermal Circulation at 49.7°E Southwest Indian Ridge Revealed by Seafloor Magnetism

AbstractDetachment faults at slow‐ and ultraslow‐spreading mid‐ocean ridges are essential for lithosphere‐hydrosphere interactions. However, their coupling with subseafloor hydrothermal circulation is poorly understood. Here, we investigated shallow hydrothermal fluid circulations in the active Dragon Horn detachment fault system of the Southwest Indian Ridge using combined near‐bottom magnetic anomaly data and rock magnetic analyses. We observed enhanced magnetic anomalies related to the high magnetization of basaltic country rocks and highly serpentinized (>80%) peridotite, whereas the hydrothermally altered basalts and sulfide deposits had weak magnetization and reduced magnetic anomalies. Therefore, the low‐magnetization zone was interpreted as a proxy for the hydrothermal fluid channel. The spatial distribution of the low‐magnetization zone revealed that the inactive Suye field expanded more than 500 m in diameter horizontally and ∼100 m vertically, and the active Longqi hydrothermal field had a >1 km fluid channel, both centered around the detachment fault fracture zone. Our results establish a robust link between detachment faulting and shallow hydrothermal circulation in which the detachment fault system provides critical fluid paths. Therefore, detachment tectonics are important elements for evolving seafloor hydrothermal fields along the Southwest Indian Ridge and possibly other slow‐ and ultraslow‐spreading mid‐ocean ridges globally.

Brain-inspired computing with fluidic iontronic nanochannels

The brain's remarkable and efficient information processing capability is driving research into brain-inspired (neuromorphic) computing paradigms. Artificial aqueous ion channels are emerging as an exciting platform for neuromorphic computing, representing a departure from conventional solid-state devices by directly mimicking the brain's fluidic ion transport. Supported by a quantitative theoretical model, we present easy-to-fabricate tapered microchannels that embed a conducting network of fluidic nanochannels between a colloidal structure. Due to transient salt concentration polarization, our devices are volatile memristors (memory resistors) that are remarkably stable. The voltage-driven net salt flux and accumulation, that underpin the concentration polarization, surprisingly combine into a diffusionlike quadratic dependence of the memory retention time on the channel length, allowing channel design for a specific timescale. We implement our device as a synaptic element for neuromorphic reservoir computing. Individual channels distinguish various time series, that together represent (handwritten) numbers, for subsequent in silico classification with a simple readout function. Our results represent a significant step toward realizing the promise of fluidic ion channels as a platform to emulate the rich aqueous dynamics of the brain.

Capacity-Aware Wash Optimization with Dynamic Fluid Scheduling and Channel Storage for Continuous-Flow Microfluidic Biochips

Capacity-Aware Wash Optimization with Dynamic Fluid Scheduling and Channel Storage for Continuous-Flow Microfluidic Biochips

Programmed Internal Reconfigurations in a 3D-Printed Mechanical Metamaterial Enable Fluidic Control for a Vertically Stacked Valve Array.

Microfluidic valves play a key role within microfluidic systems by regulating fluid flow through distinct microchannels, enabling many advanced applications in medical diagnostics, lab-on-chips, and laboratory automation. While microfluidic systems are often limited to planar structures, 3D printing enables new capabilities to generate complex designs for fluidic circuits with higher densities and integrated components. However, the control of fluids within 3D structures presents several difficulties, making it challenging to scale effectively and many fluidic devices are still often restricted to quasi-planar structures. Incorporating mechanical metamaterials that exhibit spatially adjustable mechanical properties into microfluidic systems provides an opportunity to address these challenges. Here, we have performed systematic computational and experimental characterization of a modified re-entrant honeycomb structure to generate a modular metamaterial for an active device that allows us to directly regulate flow through integrated, multiplexed fluidic channels "one-at-a-time," in a manner that is highly scalable. We present a design algorithm so that this architecture can be extended to arbitrary geometries, and we expect that by incorporation of mechanical metamaterial designs into 3D printed fluidic systems, which themselves are readily expandable to any complex geometries, will enable new biotechnological and biomedical applications of 3D printed devices.

Shape Programmable and Multifunctional Soft Textile Muscles for Wearable and Soft Robotics

Textiles are promising candidates for use in soft robots and wearable devices due to their inherent compliance, high versatility, and skin comfort. Planar fluidic textile‐based actuators exhibit low profile and high conformability, and can seamlessly integrate additional components (e.g., soft sensors or variable stiffness structures [VSSs]) to create advanced, multifunctional smart textile actuators. In this article, a new class of programmable, fluidic soft textile muscles (STMs) that incorporate multilayered silicone sheets with embedded fluidic channels is introduced. The STMs are scalable and fabricated by apparel engineering techniques, offering a fabrication approach able to create large‐scaled multilayered structures that can be challenging for current microfluidic bonding methods. They are also highly automation compatible due to no manual insertion of elastic tubes/bladders into textile structures. Liquid metal is employed for creating fluidic channels. It is not only used for actuation but also used as channels for additional features such as soft piezoresistive sensors with enhanced sensitivity to STMs’ pressure‐induced elongation, or VSSs of either low‐melting‐point alloys or a new thermo‐responsive epoxy with low viscosity and transition temperature. The STMs hold promising prospects for soft robotic and wearable applications, which is demonstrated by an example of a textile‐based wearable 3D skin‐stretch haptic interface.

RUNX1-BMP2 promotes vasculogenic mimicry in laryngeal squamous cell carcinoma via activation of the PI3K-AKT signaling pathway

BackgroundLaryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors of the head and neck. Vasculogenic mimicry (VM) is crucial for tumor growth and metastasis and refers to the formation of fluid channels by invasive tumor cells rather than endothelial cells. However, the regulatory mechanisms underlying VM during the malignant progression of LSCC remain largely unknown.MethodsGene expression and clinical data for LSCC were obtained from the TCGA and Gene GEO (GSE27020) databases. A risk prediction model associated with VM was established using LASSO and Cox regression analyses. Based on their risk scores, patients with LSCC were categorized into high- and low-risk groups. The disparities in immune infiltration, tumor mutational burden (TMB), and functional enrichment between these two groups were examined. The core genes in LSCC were identified using the machine learning (SVM-RFE) and WGCNA algorithms. Subsequently, the involvement of bone morphogenetic protein 2 (BMP2) in VM and metastasis was investigated both in vitro and in vivo. To elucidate the downstream signaling pathways regulated by BMP2, western blotting was performed. Additionally, ChIP experiments were employed to identify the key transcription factors responsible for modulating the expression of BMP2.ResultsWe established a new precise prognostic model for LSCC related to VM based on three genes: BMP2, EPO, and AGPS. The ROC curves from both TCGA and GSE27020 validation cohorts demonstrated precision survival prediction capabilities, with the nomogram showing some net clinical benefit. Multiple algorithm analyses indicated BMP2 as a potential core gene. Further experiments suggested that BMP2 promotes VM and metastasis in LSCC. The malignant progression of LSCC is promoted by BMP2 via the activation of the PI3K-AKT signaling pathway, with the high expression of BMP2 in LSCC resulting from its transcriptional activation by runt-related transcription factor 1 (RUNX1).ConclusionBMP2 predicts poor prognosis in LSCC, promotes LSCC VM and metastasis through the PI3K-AKT signaling pathway, and is transcriptionally regulated by RUNX1. BMP2 may be a novel, precise, diagnostic, and therapeutic biomarker of LSCC.

Label-free and amplification-free viral RNA quantification from primate biofluids using a trapping-assisted optofluidic nanopore platform

Viral outbreaks can cause widespread disruption, creating the need for diagnostic tools that provide high performance and sample versatility at the point of use with moderate complexity. Current gold standards such as PCR and rapid antigen tests fall short in one or more of these aspects. Here, we report a label-free and amplification-free nanopore sensor platform that overcomes these challenges via direct detection and quantification of viral RNA in clinical samples from a variety of biological fluids. The assay uses an optofluidic chip that combines optical waveguides with a fluidic channel and integrates a solid-state nanopore for sensing of individual biomolecules upon translocation through the pore. High specificity and low limit of detection are ensured by capturing RNA targets on microbeads and collecting them by optical trapping at the nanopore location where targets are released and rapidly detected. We use this device for longitudinal studies of the viral load progression for Zika and Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infections in marmoset and baboon animal models, respectively. The up to million-fold trapping-based target concentration enhancement enables amplification-free RNA quantification across the clinically relevant concentration range down to the assay limit of RT-qPCR as well as cases in which PCR failed. The assay operates across all relevant biofluids, including semen, urine, and whole blood for Zika and nasopharyngeal and throat swab, rectal swab, and bronchoalveolar lavage for SARS-CoV-2. The versatility, performance, simplicity, and potential for full microfluidic integration of the amplification-free nanopore assay points toward a unique approach to molecular diagnostics for nucleic acids, proteins, and other targets.

Plasmon near-field coupling and universal scaling behavior in shifted-core coaxial nano-cavity pair

We computationally and analytically investigate the plasmon near-field coupling phenomenon and the associated universal scaling behavior in a pair of coupled shifted-core coaxial nano-cavities. Each nano-cavity is composed of an InGaAsP gain medium sandwiched between a silver (Ag) core and an Ag shell. The evanescent coupling between the cavities lifts the degeneracy of the cut-off free transverse electromagnetic (TEM) like mode. The mode splitting of the supermodes is intensified by shifting the metal core position, which induces symmetry breaking. This coupling phenomenon is explained with spring-capacitor analogy and circuit analysis. The numerical simulation results reveal an exponential decay in the fractional plasmon wavelength relative to the ratio of gap distance and core shifting distance, which aligns with the plasmon ruler equation. In addition, by shifting the Ag cores in both cavities toward the center of the coupled structure, the electromagnetic field becomes strongly localized in nanoscale regions (hotspots) in the gain medium between the cavities, thus achieving extreme plasmonic nanofocusing. Utilizing this nanofocusing effect, we propose a refractive index sensor by placing a fluidic channel between the two cavities in close vicinity to the hotspots and reaching the highest sensitivity of ∼700nm/RIU.

Solidified water at room temperature hosting tailored fluidic channels by using highly anisotropic cellulose nanofibrils

Highly anisotropic cellulose nanofibrils can solidify liquid water, creating self-supporting structures by incorporating a tiny number of fibrils. These fibrillar hydrogels can contain as much as 99.99 wt% water. The structure and mechanical properties of fibrillar networks have so far not been completely understood, nor how they solidify the bulk water at such low particle concentrations. In this work, the mechanical properties of cellulose fibrillar hydrogels in the dilute regime from a wt% perspective have been studied, and an elastoplastic model describing the network structure and its mechanics is presented. A significant insight from this work is that the ability of the fibrils to solidify water is very dependent on particle stiffness and the number of contact points it can form in the network structure. The comparison between the experimental results and the theoretical model shows that the fibrillar networks in the dilute regime form via a non-stochastic process since the fibrils have the time and freedom to find contact points during network formation by translational and rotational diffusion. The formed, dilute fibrillar network deforms by sliding fibril contacts upon straining the network beyond its elastic limit. Our results also show that before macroscopic failure, the fibril contacts are restored once the load is released. The exceptional properties of this solidified water are exploited to host fluidic channels, allowing directed fluid transportation in water. Finally, the microfluidic channels formed in the hydrogels are tailored by the layer-by-layer technique to be interactive against external stimuli, a characteristic envisioned to be useful in biomedical applications.

Mechanisms of fluid degassing in shallow magma chambers control the formation of porphyry deposits

Abstract Magmatic fluid degassing within shallow magma chambers underneath the ore bodies is critical to the formation of porphyry Cu-Au deposits (PCDs). Yet, it remains unclear that how the ways of fluid degassing influence on the development of PCDs. Here, geochemical data of apatite, amphibole and plagioclase from ore-forming and coeval barren porphyries have been analyzed in Sanjiang metallogenic belt, China. The ore-forming porphyries normally exhibit high and wide XF/XCl (31.76-548.12) and XF/XOH (0.779-7.370) ratios of apatites, which are evidently higher than those of the barren porphyries (XF/XCl of 1.03-26.58; XF/XOH of 0.686-3.602). Combined with the continuous variation features of Cl/OH ratios and H2O contents of melts calculated by amphiboles, as well as fluid migration models, we constrained the mechanisms of fluid degassing within shallow magma chambers underneath PCDs. There are three different ways of fluid degassing, while only fluid degassing via fluid channel stage can migrate and focus the metal-rich fluids effectively, conducive to the development of PCDs. The mechanisms of magmatic fluid degassing processes are further controlled by the storage depths of magma chambers and initial H2O contents of the magmas revealed by the compositions of amphibole, plagioclase and thermodynamic modelling. Magmas, with shallower storage depth and higher initial H2O content, are more likely to experience extensive and focused fluid degassing, leading to the generation of PCDs. This study demonstrates the potential utility of integrated mineral analyses, the thermodynamic modelling for investigating the mechanisms of magmatic fluid degassing in porphyry systems, as well as identifying prospective buried PCDs.

Analytical solutions for dispersions and waveforms of acoustic logging in a cased hole

Acoustic logging is one of the most promising methods for the quantitative evaluation of cement bond conditions in cased holes. However, inefficient use of full-wave information yields unsatisfactory interpretation accuracy. Fundamentally, this is because the wavefield characteristics have not been thoroughly investigated under various cement bonding conditions. Thus, this study derives analytical solutions of wavefields for a single-cased-hole model and emphasizes the dispersion calculation algorithm. To solve the dispersion equation when solving for the poles of the propagating modes with real wavenumbers, we renormalize the Bessel function related to the borehole fluid by multiplying it with an attenuation factor. For leaky modes with complex wavenumbers, we develop a novel method to find local peaks of the matrix condition number (LPMCN) in the frequency domain to determine dispersion poles, avoiding the local optimization issues resulting from the traditional Gauss-Newton iteration method. Combining these two methods, we establish a fast and accurate workflow for evaluating the dispersion of all modes in cased holes using a relatively fast bisection method to manage the dispersion of the propagating modes and using the LPMCN method to derive the dispersion curves of leaky modes. Furthermore, all propagating modes are individually investigated in the monopole measurement by evaluating the residues of the real poles in a casing-free model. The analysis demonstrates that the first-order pseudo-Rayleigh wave (PR1) and inner Stoneley wave (ST1) are the two strongest modes. Finally, we focus on the waveforms and dispersion characteristics of the outer Stoneley wave (ST2) related to the fluid channel in the cement annulus. The results reveal that as the fluid thickness increases, the phase velocity of the ST2 mode decreases, and its amplitude increases. Therefore, the ST2 mode can potentially evaluate the thickness of the fluid channel in a cement annulus if an effective weak-signal-extraction method is used.

Thermoelectric performance analysis of the novel direct-expansion photovoltaic thermal heat pump/power heat pipe compound cycle system in summer

Photovoltaic thermal heat pump technology has outstanding cogeneration ability by utilizing renewable energy to be accepted as a decarbonization pathway in the residential sector. However, existing photovoltaic thermal heat pumps consume higher energy under better external heat source conditions. To address this problem, a novel direct-expansion photovoltaic thermal heat pump/power heat pipe compound cycle system for heating and power generation as well as refrigeration, whose core equipment was a photovoltaic thermal module with straggled honeycomb fluid channel pattern on the serpentine arrangement, was proposed, manufactured, and studied with the method of experiment. The thermoelectric performance was compared between the heat pump and power heat pipe cycle modes, investigated under typical weather conditions, and discussed in contrast to the literature. The results showed that the average photoelectric conversion efficiency and coefficient of photothermal performance of the PVT modules, as well as COP of the novel system were 10.6%, 51.0%, and 6.19, respectively, at the average ambient temperature of 27.0 °C, average solar radiation intensity of 581 W/m2 and water temperature of 18.3–55.6 °C. And daily average COPs of the novel system under sunny, cloudy, and overcast conditions were 15.12, 7.40, and 3.17, respectively. The conclusion drawn from the experimental results is that the COP of the novel system was 10.0%–60.0% higher than that in the literature under similar outdoor conditions. The payback period of the additional cost of the novel system compared with the existing direct-expansion photovoltaic thermal heat pump was within 2.5 years. The novel system represents a practical response to the need to achieve total decarbonization of the residential sector.

Topography optimisation using a reduced-dimensional model for transient conjugate heat transfer between fluid channels and solid plates with volumetric heat source

Consideration of transient effects is important for industrial applications of heat transfer structure optimisation studies; however, the huge computational cost associated with transient problems is a pressing concern. This paper proposes an extension of a previous reduced-dimensional model to transient conjugate heat transfer between a fluid flow and solid-heated plates in a plate heat exchanger. The extended reduced-dimensional model introduces the temperature field of the plate governed by the heat conduction equation, which is coupled to the temperature field of the fluid, governed by the convection-diffusion equation, through the heat flux balance equation at the contact surface. The model is based on assumptions of fully developed flow and constant temperature profile, reducing the three-dimensional problem to a planar problem and significantly reducing computational costs. The accuracy of the model for the simulation of transient heat transfer is verified by comparison with a three-dimensional model. In this paper, the topography of the heat exchanger plate is optimised for both steady-state and transient conditions by applying the reduced-dimensional model. The effectiveness of the optimised design was demonstrated by the cross-check of both the reduced-dimensional and full three-dimensional models. Furthermore, this work considers the effect of time-independent boundary conditions and time-dependent boundary conditions on transient optimisation. The transient and steady-state optimised designs are analysed and compared for both conditions, and the necessity of transient optimisation is discussed.

Self-assembled ultrathick MoS2 conductive hydrogel membrane via ionic gelation for superior capacitive energy storage

Conductive hydrogel membranes with nanofluids channels represent one of the most promising capacitive electrodes due to their rapid kinetics of ion transport. The construction of these unique structures always requires new self-assembly behaviors with different building blocks, intriguing phenomena of colloidal chemistry. In this work, by delicately balancing the electrostatic repulsions between 2D inorganic nanosheets and the electrostatic adsorption with cations, we develop a general strategy to fabricate stable free-standing 1T molybdenum disulphide (MoS2) hydrogel membranes with abundant fluidic channels. Given the interpenetrating ionic transport network, the MoS2 hydrogel membranes exhibit a high-level capacitive performance 1.34 F/cm2 at an ultrahigh mass loading of 11.2 mg/cm2. Furthermore, the interlayer spacing of MoS2 in the hydrogel membranes can be controlled with ångström-scale precision using different cations, which can promote further fundamental studies and potential applications of the transition-metal dichalcogenides hydrogel membranes.

Measurements of nonlinear electric–acoustic interactions in liquids

Electric and acoustic waves can interact nonlinearly inside a fluid medium. These interactions can create a heterodyned signal consisting of both sum and difference frequency products of the electric and acoustic frequencies. Here, we present direct measurements of nonlinear mixing products produced by interacting electric and acoustic waves inside of various fluids. The experiment consisted of a fluid channel that was in direct contact with an electrically conductive co-planar wave guide (CPW). An acoustic signal was applied to the channel via a transducer mounted above it, and simultaneously an electric signal was applied along the CPW from a vector network analyzer (VNA). The resulting signal was then measured with VNA set to frequency offset mode to capture the sum electric-acoustic mixing product. Results are presented for various organic solvents and salt solutions, each showing a different characteristic nonlinear response. This metrology allows for direct probing of non-linear effects in electrici–acoustic systems and could lead to the development of new spectroscopic methods for characterizing chemicals and solutions.

Hydrodynamic function and spring constant calibration of FluidFM micropipette cantilevers

Fluidic force microscopy (FluidFM) fuses the force sensitivity of atomic force microscopy with the manipulation capabilities of microfluidics by using microfabricated cantilevers with embedded fluidic channels. This innovation initiated new research and development directions in biology, biophysics, and material science. To acquire reliable and reproducible data, the calibration of the force sensor is crucial. Importantly, the hollow FluidFM cantilevers contain a row of parallel pillars inside a rectangular beam. The precise spring constant calibration of the internally structured cantilever is far from trivial, and existing methods generally assume simplifications that are not applicable to these special types of cantilevers. In addition, the Sader method, which is currently implemented by the FluidFM community, relies on the precise measurement of the quality factor, which renders the calibration of the spring constant sensitive to noise. In this study, the hydrodynamic function of these special types of hollow cantilevers was experimentally determined with different instruments. Based on the hydrodynamic function, a novel spring constant calibration method was adapted, which relied only on the two resonance frequencies of the cantilever, measured in air and in a liquid. Based on these results, our proposed method can be successfully used for the reliable, noise-free calibration of hollow FluidFM cantilevers.

Simulation of hydraulic-mechanical-chemical coupled acid fracturing of rock with lattice bonds

The acid fracturing is a very important stimulation technique for carbonate reservoir. The hydraulic-mechanical-chemical effect is tightly coupled in this fracture process. In this paper, the discretized virtual internal bond is extended to simulate this coupling process in which the rock matrix is considered to consist of many discrete bond cells with finite number of bonds. Each bond is taken as transport channel of acid fluid, the reaction site of chemical dissolution and the mechanical linkage. When acid fluid flows through a bond, the bond will be dissolved. As result, both the bond porosity and permeability are increased, and the mechanical properties are weakened. By this method, the hydraulic, mechanical and chemical fields are coupled together on the micro bond. The acidization, the chemical-induced mechanical weakening and the fracture propagation can be well reproduced. This method transforms the complicated 3D multi-physical coupling problem into the 1D bond problem, which significantly simplifies the simulation of multi-field coupling process. It provides a feasible approach to simulate the HMC coupled acid fracturing process.

Advances in biomedical fluid–structure interaction: Methodologies and applications from an interfacing perspective

Fluid–structure interaction (FSI) is a nonlinear multiphysics phenomenon that describes the interactions between incompressible fluid flows and immersed structures, making it invaluable to biomedical research. In this work, the common FSI methodologies in biomedical research were systematically summarized and classified into three groups based on FSI interfaces: fluid–channel interfaces, fluid–particle interfaces, and multi-interface interactions. A discussion of the role of the numerical FSI methods was also made, outlining its indispensable advantage in handling complex geometries, boundary conditions, and thus FSI interfaces. The applications of these methods are discussed in terms of blood vessel-related applications, drug-delivering micropumps, particle dynamics/cell sorting, and particle deformation and rapture. The development progress, current advances, and prospects of FSI's future application in biomedical research were illustrated. It was concluded that with the advances in computation technologies, the rapidly developing FSI methods can achieve state-of-the-art level details, helping to improve our understanding of various biomedical-related problems and the use of FSI techniques in biomedical research is likely to continue to grow.

Pore size optimization and fluid channel analysis of composite wick and anti-gravity study

Flat plate micro heat pipes (FPMHPs) utilize the vapor–liquid two-phase circulation of the working medium to transfer heat and play an essential role in heat dissipation systems. But the effects of capillary force and porosity on the flow channel’s heat transfer characteristics and the working medium’s anti-gravity properties are not clarified. It is found in the heat transfer theory that balancing the capillary force and porosity of the composite wick can improve heat transfer efficiency, increase the maximum thermal power and anti-gravity of the FPMHP. FPMHPs with composite wicks of different pore sizes were developed and tested by the established test platform. The results indicated that the capillary force and porosity of the composite wick constrained each other, and the FPMHP made of the composite wick sintered with 80 mesh copper powder (CW80-FPMHP) had the best heat transfer characteristics and anti-gravity properties. The maximum thermal power of CW80-FPMHP is 38.6 W at 0°, which is 5.4%, 3.6%, 3.5% and 17% higher than that of CW60-FPMHP, CW70-FPMHP, CW90-FPMHP and CW100-FPMHP, respectively. At a tilt of 45°, the maximum thermal power of CW80-FPMHP is 26.27 W, which is 17.6%, 24.3%, 53.9%, 53.9%, and 51.8% higher than CW60-FPMHP, CW70-FPMHP, CW90-FPMHP, and CW100-FPMHP, respectively. In addition, the thermal resistance of the vapor channel in CW80-FPMHP is lower than that of the liquid flow channel. Gravity affects the thermal conductivity of the vapor and liquid flow channels, which in turn affects the performance of the FPMHP. Balancing the capillary force and porosity can improve the performance of the FPMHP under various operating angles.