Liquid-gas Phase Research Articles

A trade study of a phase change system in a stratospheric airship based on a triple gasbag concept

By means of regulating the volume of the phase change gasbag, a new stratospheric airship is proposed based on a triple gasbag concept (TGC), which could stay stationary at the same altitude during day and night. A trade study of the phase change system (PCS) is performed, to improve the feasibility of this kind of new stratospheric airship. Ammonia and butane based derivatives are suitable phase change working gases, particularly, ammonia has the advantage of an excellent gas mass per unit buoyancy adjustment, while butane based derivatives have the smallest power consumption per unit buoyancy adjustment. Liquefaction of the working gas by refrigerating technology is the best way and the best refrigerant is ethene, considering the power consumption and weight of the refrigeration system. The biggest advantage of butane based derivatives as the working gas is that off-the-shelf products can be applied. The weight of the PCS based on 1-butene accounts for 30% of the total buoyancy of a 5000 m3 airship, while its power consumption is only 255 W. When applying ammonia as the working gas undergoing gas-liquid phase changes, the weight of the PCS could reach lower values (18% of the total buoyancy), but the power consumption is higher (443 W).

Gas-liquid two-phase flow measurement by combining a Coriolis flowmeter with a flow conditioner and analytical models

Abstract In oil-gas fields, two phase flow measurement of liquid-gas mixture for the whole Gas Void Fraction (GVF) range remains a challenging task. Coriolis flow meter is proven to be one of the most accurate device for single phase flow measurement. However, for two phase flow metering, its accuracy gets altered for liquid continuous phase (respectively gas continuous phase) in case of GVF that exceeds 20% (respectively low GVF that is lower than 80%). This paper presents a new Coriolis-based two phase flow meter (TPFM) that uses an upstream inline flow conditioner which separates liquid (i.e. water in this paper) from gas. Each of the gas dominant phase and liquid dominant phase are carried by two outlets, namely gas and liquid outlets respectively. A Coriolis flow meter and an actuated valve are placed in each outlet to measure and regulate the GVF that passes in each line. A new measurement algorithm based on a multistage artificial neural network (ANN) and which explores the physical model of the Coriolis flow meter is also suggested. This latest combines the pressure-volume-temperature (PVT) and bubble theory models to estimate the amount of gas (respectively liquid) dissolved in the liquid phase (respectively gas phase). Experimental results that were conducted on a multiphase flow loop reveals that for the whole GVF range (i.e. 0 to 100% GVF), the absolute value of the relative error on both the mass flow rate and density does not exceed 2.5%. This suggests that the proposed TPFM can be considered as a new non-hazardous alternative for accurate two phase flow measurement.

Factors affecting kLa in Pall's iCELLis bioreactor

Background & Aim The characterization of a bioreactor-specific oxygen gas-liquid diffusion rate using the volumetric mass transfer coefficient (kLa) allows one to predict the initial process parameters for comparable cell culture growth in bioreactors of various dimensions and designs. Despite the emergence of the iCELLis bioreactor as a leading viral vector manufacturing platform, a thorough kLa characterization has not been performed thus far. Methods, Results & Conclusion The relative impact of critical process variables, such as media linear speed, falling film height, and air flow rate on kLa values in both the bench-scale iCELLis Nano, as well as the production-scale iCELLis 500+ is discussed in this poster. At identical linear speeds and falling film heights in the iCELLis Nano and iCELLis 500+, kLa values are similar at certain air flow rates: 5 mL/min in iCELLis Nano at 3 L/min in iCELLis 500+. The 1500x difference in airflow for iCELLis Nano and iCELLis 500 bioreactors with equivalent packed-bed size and compaction includes inequality in the bioreactors working volume (75x) and the contact surface area of gas-liquid phases (20x). Therefore, at higher air flow regimes, the direct process scale-up from the iCELLis Nano to the iCELLis500+ based on constant kLa and media linear speed may not be possible.

Numerical analysis of separation performance of an axial-flow cyclone for supercritical CO2-water separation in CO2 plume geothermal systems

Supercritical CO2 produced by CO2 plume geothermal systems can be used in Brayton cycles if entrained water is removed. A physical parameter analysis indicated that the supercritical CO2-water mixture presented a gas-liquid phase, and an improved axial-flow cyclone was designed to realize the separation. This study was conducted using computational fluid dynamics to simulate three parts of the flow, including continuous supercritical CO2, discrete water droplets and the water film. A Reynolds stress model was adopted to calculate turbulence, the Eulerian-Lagrangian method was applied to simulate the coupled gas-liquid two-phase flow, and the Surface Film Model was employed to predict the liquid film. The effects of the number of guide vanes on separation performance were investigated. The results of the simulations demonstrate that the increase in the number of guide vanes strengthens the tangential velocity of the continuous phase and expands the static pressure. Furthermore, it is easier for particles to move towards the wall surface and then transform into water film when the increased vane number shortens the pitch of the helical trajectories. This also contributes to the thickening of the water film, along with an increment in film velocity. It is obtained that more guide vanes could improve the removal efficiency of the water droplets while increasing the pressure drop. Erosion analysis indicates the separator with 6 vanes suffers the most severe erosion. A comprehensive economic assessment shows that the design of 8 vanes is the most economically friendly option.

On experimental and numerical study of the dynamics of a liquid metal jet hit by a laser pulse

In this paper, we present an experimental and numerical study of the laser pulse impact on the liquid metal jet target. The jet motion was recorded with the stroboscopic ultrafast shadow photography. Simulations were carried out in a two-step approach. At the first step, we simulated laser interaction with the target using the radiation hydrodynamics code 3DLINE, which accounts for a number of effects: liquid–gas phase transition, dynamics of ionization, radiation transfer, laser reflection, refraction and absorption. However, this code cannot be used on a deeply refined mesh near the liquid surface and does not account for the surface tension, which strongly affects liquid motion on the microsecond timescale after the laser pulse ends. Therefore, for the second step we employed the OpenFOAM solver, based on the volume-of-fluid method, which overcomes these limitations. The simulated target dynamics is found to be in a fairly good agreement with the experiment.

When and why do gradients of the gas phase composition and pressure affect liquid-gas transfer?

Gas bubbles are introduced in water to absorb or strip volatile substances in a variety of unit operations, for example during (waste)water treatment. To calculate the transfer rate of substances between the liquid phase and the gas phase, different assumptions have been made in literature regarding the gas phase composition and hydraulic pressure, which both vary along the reactor height. In this study, analytical expressions were derived for the total (macroscopic) liquid-gas transfer rate, using either the complete gradients of the mole fraction and pressure (comprehensive approach) or a uniform value, for one or both of them. Simulations with the comprehensive model were performed to understand the effect of the type of volatile substance and of the reactor design and operating conditions on the total liquid-gas transfer rate. These effects were found to be highly interactive and often non-linear. Next, the simulation results of the comprehensive model were compared with those from models that assume either a uniform mole fraction or a uniform pressure in the complete reactor volume. This illustrated that for soluble substances, the mole fraction gradient strongly affects the total liquid-gas transfer rate, while the pressure gradient became only important under operating conditions that promote stripping (i.e., for a high concentration in the liquid phase and low concentration in the inlet gas). For very poorly soluble substances, the pressure became more important under conditions that promote absorption. These results on the importance of the mole fraction and pressure gradients remained equally valid when explicitly considering a typical variation of the volumetric overall transfer coefficient (KLa) along the reactor height. Finally, a simple and fast procedure was made available through a spreadsheet to select appropriate simplifying assumptions in reactor or plant-wide models. By applying the procedure to oxygen (O2), carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and nitrogen gas (N2) in an aerobic biological wastewater treatment reactor, it was demonstrated that some common simplifications can lead to significant errors, for which corrections were proposed.

Strain-Induced Crystallization in Natural Rubber: Flory’s Theory Revisited

In this paper, some aspects of the physical mechanisms involved in strain-induced crystallization (SIC) in cross-linked natural rubber networks are discussed. The theory of SIC as developed by Flory is considered within a somehow innovative perspective, in analogy to the liquid–gas phase transformation. A simple lever rule is proposed to relate the crystallinity index to the local and global draw ratios. Equilibrium properties are considered first. Some simple experiments are discussed within this framework to enlighten some fundamental aspects of SIC. As the order parameter for SIC is the draw ratio of the amorphous phase, the importance of directly measuring this parameter is emphasized. Special emphasis is put on the relaxation of the remaining amorphous fraction that accompanies SIC. The question of crystallization kinetics underlies most aspects of SIC. We show that the actual time dependence of the crystalline content may be related to the mechanism of strain relaxation in a quite simple manner using the lever rule mentioned above. Crystallization kinetics is also fundamental to explain the hysteretic behavior observed in dynamical conditions. Similarities and differences with static SIC are discussed. We transpose the classical theory of nucleation to the case of SIC, and we discuss the kinetics within this framework.

Fluid critical behavior at liquid–gas phase transition: Analytic method for microscopic description

The behavior of fluids in the vicinity of the liquid–gas critical point is studied within the cell fluid model framework. The analytic method for deriving the equation of state of a cell fluid model in the low-temperature region (T < Tc) is developed using the renormalization group transformation within the collective variables approach. Mathematical description within the grand canonical ensemble is illustrated by an example of the Morse interaction potential possessing the Fourier transform. A specific feature of the proposed method lies in the possibility to use exclusively microscopic characteristics of a fluid (parameters of the interaction potential) for calculating macroscopic quantities (pressure and other thermodynamic quantities) without involving the hard-spheres reference system. The grand partition function, thermodynamic potential, and equation of state of the model near the critical point are derived taking into account the non-Gaussian (quartic) distribution of order parameter fluctuations. A nonlinear equation, which links the density and the chemical potential, is presented and solved. Graphs of the dependence of the density on the chemical potential are plotted for various values of the relative temperature. The numerical estimates of the critical-point parameters for potassium, obtained in addition to the estimates for sodium, are given. The calculated critical-point parameters for liquid alkali metals (sodium and potassium) are in accord with experimental data. The coexistence curve for sodium is plotted and compared with other authors' data in the immediate vicinity of Tc, where theoretical and experimental researches are difficult to carry out. The differences between the obtained results and the earlier published results for T > Tc are discussed.

Influence of pre-freezing conditions of octacalcium phosphate and collagen composite for reproducible appositional bone formation.

Even though conventionally prepared octacalcium phosphate and collagen composite (OCP/Col) has exhibited excellent bone regeneration and has recently been commercialized for treating bone defects, reproducible appositional bone formation with OCP/Col has never been achieved. The present study investigated whether appositional bone formation could be achieved by altering the density of OCP/Col and applying liquid nitrogen during the preparation of OCP/Col. The prepared OCP/Col disks had eight variations and were divided into categories according to four different type of densities (1.0, 1.3, 1.7, and 2.0) of OCP/Col and two different pre‐freezing conditions of gas phase (G group: −80°C) and liquid phase (L group: −196°C). These disks were implanted into subperiosteal pockets in rodent calvaria, five samples per each eight variations. Radiomorphometric analysis was conducted at 4 and 12 weeks after implantation, and histological analysis was conducted at 12 weeks after implantation. OCP/Col samples in the L group tended to retain their height and shape and had enhanced appositional bone formation, whereas OCP/Col samples in the G group tended to lose their height and shape and had limited appositional bone formation. The appositional bone formation increased along with growing density of OCP/Col, and L2.0 demonstrated higher appositional bone formation than other samples. These results suggest that the pre‐freezing conditions and densities of OCP/Col affect the appositional bone formation.

Role of the Support in Gold-Containing Nanoparticles as Heterogeneous Catalysts.

In this review, we discuss selected examples from recent literature on the role of the support on directing the nanostructures of Au-based monometallic and bimetallic nanoparticles. The role of support is then discussed in relation to the catalytic properties of Au-based monometallic and bimetallic nanoparticles using different gas phase and liquid phase reactions. The reactions discussed include CO oxidation, aerobic oxidation of monohydric and polyhydric alcohols, selective hydrogenation of alkynes, hydrogenation of nitroaromatics, CO2 hydrogenation, C–C coupling, and methane oxidation. Only studies where the role of support has been explicitly studied in detail have been selected for discussion. However, the role of support is also examined using examples of reactions involving unsupported metal nanoparticles (i.e., colloidal nanoparticles). It is clear that the support functionality can play a crucial role in tuning the catalytic activity that is observed and that advanced theory and characterization add greatly to our understanding of these fascinating catalysts.

Atmospheric microplasma based binary Pt3Co nanoflowers synthesis

The atmospheric microplasma in the gas-liquid phase technique serves as a new potential efficient and green catalyst preparation technique to fabricate nanomaterials. Due to the presence of diverse reactive species, this technique can promote rapid complex reactions in solutions, which are typically sluggish in traditional chemical processes. Here, atmospheric microplasma induced liquid chemistry (AMILC) is applied to fabricate three-dimensional (3D) binary Pt3Co nanoflowers. Nano-architectures of Pt3Co bimetals (2D nanosheets and 3D nanoflowers) can be formed by tuning the initial cobalt molar concentration in the solution. 3D nanoflowers show a ‘nano-bouquet’ like nanostructure with Co-oxide forming leaves and Pt3Co forming waxberries. 3D nanoflowers show promising electrocatalytic behavior towards ethanol and glucose sensing in alkaline condition. Additionally, AMILC takes less synthesis duration (~10 min) without hazardous chemicals for Pt3Co bimetal nanostructure preparation compared to conventional chemical approaches (>2 h), indicating that AMILC is a potential candidate with better energy efficiency, lower carbon footprint and green plasma chemistry process for 3D nanostructure material synthesis in catalyst applications.

Performance of an atmospheric plasma discharge reactor for inactivation of Enterocococcus faecalis and Escherichia coli in aqueous media

Several non-thermal plasma-based systems have been explored for the treatment of water. In this study, the performance of an atmospheric pressure gas-liquid phase air non-thermal plasma (NTP) reactor to inactivate both gram-positive (Enterococcus faecalis (E. faecalis)) and gram-negative (Escherichia coli (E. coli)) bacterial species was studied. The time-dependent effects of different applied voltages (2 kV, 4 kV, and 6 kV) on microbial decontamination were investigated in addition to changes in solution pH, conductivity and electrode temperature. Moreover, reactive oxygen species (ROS), hydroxyl radical (OH) and ozone formed during NTP treatment were quantified. Scanning Electron Microscopy (SEM) analysis revealed alterations in the morphological structure of bacteria with NTP treatment. As compared with gram-negative bacteria, gram-positive bacteria was found to be more susceptible to NTP disinfection effects. Inactivation kinetics of E. faecalis and E. coli was studied in detail and complete inactivation of E. faecalis and E. coli was observed in 10 min (4 kV) and 15 min (6 kV), respectively. Results confirm that NTP treatment of water is a promising approach for the decontamination of pathogenic bacterial species.

Temperature and phase evolution and density distribution in cross section and sound evolution during the release of dense CO2 from a large-scale pipeline

Global warming represents substantial and severe challenges for human beings today. As one of the most worth ways to slowing the global warming, Carbon Capture Utilization and Storage (CCUS) is promising technology receiving more attention. As an important link, CO2 should be safe transportation from capture point to storage point. Pipeline transportation is most economical and more research is required to ensure safe operation. To carry out large-scale pipeline safety studies, a 258 m long and 233 mm inner diameter pipeline was built and many pressure sensors and several thermocouples were used to measure the many parameters during the CO2 release process. This paper, the dense CO2 was released from the diameter of 50 mm release orifice. And multi-dimensional characteristic of CO2 had been focused during the release from the pipeline. The temperature was measured through six cross sections inside pipeline and the temperature evolution on each cross section was obtained. At each point temperature evolution deviated from overall trend gradually from top to down at each cross section. The evolutions of phase and density were obtained using the temperature and pressure data. When the CO2 phase transformed into gas-liquid phase, the phase of CO2 maintained at gas-liquid phase for a moment. At each cross section, the phase transformed from gas-liquid to gas gradually from up to down. At far away from the release part of pipeline, the phase evolution transformed at triple point. In addition, at the beginning of the release period, the density evolution was drastic, and with the experiment continued the density evolution became more gradual. Sound was created during the release process. Hence, the value of sound was measured around the release orifice and evolution of sound was discussed.

Planar dynamics of inclined curved flexible riser carrying slug liquid–gas flows

Flexible risers transporting hydrocarbon liquid–gas flows may be subject to internal dynamic fluctuations of multiphase densities, velocities and pressure changes. Previous studies have mostly focused on single-phase flows in oscillating pipes or multiphase flows in static pipes whereas understanding of multiphase flow effects on oscillating pipes with variable curvatures is still lacking. The present study aims to numerically investigate fundamental planar dynamics of a long flexible catenary riser carrying slug liquid–gas flows and to analyse the mechanical effects of slug flow characteristics including the slug unit length, translational velocity and fluctuation frequencies leading to resonances. A two-dimensional continuum model, describing the coupled horizontal and vertical motions of an inclined flexible/extensible curved riser subject to the space–time varying fluid weights, flow centrifugal momenta and Coriolis effects, is presented. Steady slug flows are considered and modelled by accounting for the mass–momentum balances of liquid–gas phases within an idealized slug unit cell comprising the slug liquid (containing small gas bubbles) and elongated gas bubble (interfacing with the liquid film) parts. A nonlinear hydrodynamic film profile is described, depending on the pipe diameter, inclination, liquid–gas phase properties, superficial velocities and empirical correlations. These enable the approximation of phase fractions, local velocities and pressure variations which are employed as the time-varying, distributed parameters leading to the slug flow-induced vibration (SIV) of catenary riser. Several key SIV features are numerically investigated, highlighting the slug flow-induced transient drifts due to the travelling masses, amplified mean displacements due to the combined slug weights and flow momenta, extensibility or tension changes due to a reconfiguration of pipe equilibrium, oscillation amplitudes and resonant frequencies. Single- and multi-modal patterns of riser dynamic profiles are determined, enabling the evaluation of associated bending/axial stresses. Parametric studies reveal the individual effect of the slug unit length and the translational velocity on SIV response regardless of the slug characteristic frequency being a function of these two parameters. This key observation is practically useful for the identification of critical maximum response.

Two-Dimensional Free-Surface Flow Modeling for Wave-Structure Interactions and Induced Motions of Floating Bodies

In this study, the level set (LS) and immersed boundary (IB) methods were integrated into a Navier–Stokes equation two-phase flow solver, to investigate wave-structure interactions and induced motions of floating bodies in two dimensions. The movement of an interfacial boundary of two fluids, even with severe free-surface deformation, is tracked by using the level set method, while an immersed object inside a fluid domain is treated by the IB method. Both approaches can be implemented by solving the Navier–Stokes equations for viscous laminar flows with embedded objects in fluids. For accurate treatment of the solid–liquid phase, appropriate source terms as forcing functions to take into account the hydrodynamic effects on the body boundaries are added into the governing equations. The integrated compact interfacial tracking techniques between the interfaces of gas–liquid phase and the solid–liquid phase allow the use of a combined Eulerian Cartesian and Lagrangian grid system. Problems related to the fluid-structure interactions and induced motions of a floating body, such as (a) a dam-break wave over a dry bed; (b) a dam-break wave over either a submerged semicircular or rectangular cylinder; (c) wave decomposition process over a trapezoid breakwater; (d) a free-falling wedge into a water body; and (e) wave packet interacting with a floating body are selected to test the model performance. For all cases, the computed results are found to agree reasonably well with published experimental data and numerical solutions. For the case of modeling wave decomposition process, improved solutions are obtained. The detailed features of flow phenomena described by the physical variables of velocity, pressure and vorticity are presented and discussed. The present two-phase flow model is proved to have the advantage of simulating the cases with induced severe interfacial oscillations and coupled gas (or air) motions where the single-phase model may miss the contributions of the air motions on the interfaces. Additionally, the proposed method with uses of the LS and IB methods is demonstrated to be able to achieve the reliable predictions of complex flow fields.

Origin of ferromagnetism in Sm-doped In2S3 nanoparticles: Experimental and theoretical insights

Diluted magnetic semiconductors with room-temperature ferromagnetism (RTFM) opens new prospects for the development of next-generation spintronic devices. For now, the rare earth doping is an effective method to tune the ferromagnetism of semiconductor materials. In this work, we fabricated undoped In2S3 and In2S3: Sm3+ nanoparticles using gas-liquid phase chemical deposition method. UV–visible and photoluminescence spectra demonstrate that the introduction of Sm3+ ions lead to bandgap narrowing and enhanced luminescence intensity. Magnetic characterizations show that all synthetic samples display a ferromagnetic behaviour, and the maximum saturation magnetization of the samples can be tuned by regulating the concentration of doped Sm3+ ions. The RTFM in Sm doped In2S3 nanoparticles derives from the coupling interaction between the localized defect states and Sm3+ ions and is described using bound magnetic polarons (BMPs) mechanism. First-principle calculations reveal that In vacancies and Sm dopants are responsible for the generation of magnetic moments which come mainly from S 3p orbitals around the In vacancy and Sm 4f orbitals. Our results suggest that In2S3: Sm3+ nanoparticles constitute promising semiconductor materials for use in future electronic and spintronic devices.

Knoevenagel condensation versus Michael addition reaction in ionic-liquid-catalyzed synthesis of hexahydroquinoline: a SMD–DFT study

Knoevenagel condensation and Michael addition reaction are two different mechanisms for C–C bond formation. In this work, M06-2X method is used to compare activation free energies of Knoevenagel condensation and Michael addition reaction in the gas and ionic liquid phases. The role of 2-ethyl imidazolium hydrogen sulfate in the synthesis of hexahydroquinolines is investigated. To model ionic liquid phase, SMD continuum universal solvation model is used. Data show that Knoevenagel condensation and Michael addition have activation free energies of 45 and 13 kcal mol−1 in the gas phase and + 24 and + 12 kcal mol−1 in the ionic solution phase, respectively. The final cyclization process has zero barrier energy. Analyzing TS structures by the quantum theory of atoms in molecules (QTAIM) show that the TS structure of Knoevenagel step is similar to the product, while the TS structure of Michael addition step is similar to the reactants.

Novel Multifunctional Nanoagent for Visual Chemo/Photothermal Therapy of Metastatic Lymph Nodes via Lymphatic Delivery.

Breast cancer is one of the major diseases that threaten women’s health. Lymph node (LN) metastasis is the most common metastatic path of breast cancer. Finding a simple, effective, and safe strategy to eliminate metastatic tumors in LNs is highly desired for clinical use. Carbon nanoparticles (CNs), as an LN tracer, have been widely used in the clinical setting. In addition, previous experiments have confirmed that CNs have good photoacoustic imaging and photothermal effects. In this study, we used CNs as a photothermal conversion material and drug carrier, poly(lactic-co-glycolic acid) (PLGA) as a film-forming material, and docetaxel as a chemotherapy drug to prepare multifunctional nanoparticles (DOC-CNPs). The prepared DOC-CNPs present as a black solution, which shows smooth spherical particles under light microscopy and transmission electron microscopy (TEM), and they have a good ability for liquid–gas phase transition, good dispersibility, high drug-loading capacity, and low cytotoxicity. In vitro, they can release drugs and inhibit tumor cells after laser irradiation. The photoacoustic (PA) signal intensity and the photothermal conversion efficiency increased with an increase in the concentration of DOC-CNPs. In vivo, after administration, the DOC-CNPs reached the LNs. After laser irradiation, the DOC-CNPs absorbed laser energy, and the temperature of the LNs increased high enough to achieve photothermal therapy under PA and ultrasound monitoring. Fracture of the DOC-CNPs was caused by the liquid–gas phase transition with the increased temperature, and the ruptured DOC-CNPs released docetaxel to achieve targeted chemotherapy. These findings suggested that DOC-CNPs can achieve precise treatment for metastatic LNs of breast cancer with PA and ultrasound visualization.

Experimental Investigation of Thermophysical Properties and Combustion Characteristics of Thickened Jet Fuel

ABSTRACT The thermophysical properties and combustion characteristics of PIB thickened jet fuel are investigated based upon both aims of expanding basic combustion theory (i.e., the coupled gas phase and liquid phase flows and heat transfer involving flame spread over liquid fuel) and potential practical applications (i.e., the oil additive in two-stroke gasoline engine and in-situ burning of leaked oils). The effects of PIB on the thermophysical parameters of jet fuel including density, flashpoint, viscosity and surface tension are experimentally measured. The logarithm of the dynamic viscosity varies linearly with the proportion of PIB, which is in good agreement with predictions. Then, the impact of PIB on fire safety of jet fuel is examined through flame spread and ignition experiments. The temperature evolution, flame spread rate, length and velocity of subsurface flow are quantitated and analyzed. The addition of PIB into jet fuel reduces the flame spread rate, but promotes the ignitability. The viscosity augment plays the principal role in hindering flame spreading over thickened jet fuel.

폐열에너지로 구동되는 자성나노유체-버블 2상유동 사이클 나노발전 시스템

As a part of energy conversion technology, we proposed a cycle nanogenerator to produce electric energy through magnetic nanofluid (MNF) flow using waste heat energy from the industry. In the proposed nanogenerator, a heat source causes self-circulation of working fluid by thermosiphon method, and two-phase flow of MNF-bubbles resulting in density difference in the gas-liquid phase. For this reason, the spatial discretization of the magnetic field occurs under an external magnetic field and the induced electromotive force is generated in a solenoid coil by Faraday