Operating Regimes Research Articles

Experimental analysis of a novel confined bed system for thermal energy storage

Thermal energy storage (TES) is an essential subsystem for the uniform operation of concentrated solar power (CSP) plants. A sensible heat storage system based on a novel confined bed of small particle size granular material was experimentally evaluated. The bed of regular silica sand was mechanically confined between a bottom and a top perforated plate gas distributor, to prevent the motion of particles even for gas velocities above the minimum fluidization velocity of the solids, operating the bed under a fixed or packed bed regime. The discharge process of the confined bed was experimentally analyzed, preheating the granular material at 300–320 °C and supplying various volumetric flow rates of cold air through the bottom distributor. During the discharge process, the temperature of the bed was segregated, obtaining a high temperature zone at the top region and a low temperature zone at the bottom region of the bed. These regions are separated by a thermocline that evolves in the upwards direction as the discharge process progresses. The temperature distribution in the bed and the total pressure drop of the TES system were monitored during the tests. For all cases, the temperature of the bed at different heights evolves as in a fixed bed, confirming the proper confinement of the granular material. The thermocline velocity depends on the volumetric flow rate of cold air, obtaining a discharge time for the temperature located at the exit of the system of around 50, 40, and 30 min for air volumetric flow rates of 700, 900, and 1100 Nlpm, respectively, using 55 kg of regular silica sand as granular material. The experimental results of the evolution and distribution of temperature in the bed were compared with an analytical model of the process for a fixed/packed bed regime of operation, resulting in a good agreement between the experimental measurements and the numerical predictions.

Spatial organization and proteome of a dual-species cyanobacterial biofilm alter among N2-fixing and non-fixing conditions.

Many disciplines have become increasingly interested in cyanobacteria, due to their ability to fix CO2 while using water and sunlight as electron and energy sources. Further, several species of cyanobacteria are also capable of fixing molecular nitrogen, making them independent of the addition of nitrate or ammonia. Thereby they hold huge potential as sustainable biocatalysts. Here, we look into a dual-species biofilm consisting of filamentous diazotrophic cyanobacteria Tolypothrix sp. PCC 7712 and heterotrophic bacteria Pseudomonas taiwanensis VLB 120 growing in a capillary biofilm reactor. Such systems have been reported to enable high cell densities continuous process operation. By combining confocal laser scanning and helium-ion microscopy with a proteomics approach, we examined these organisms' interactions under two nitrogen-feeding strategies: N2-fixing and nitrate assimilation. Not only did Pseudomonas facilitate the biofilm formation by forming a carpet layer on the surface area but also did N2-fixing biofilms show greater attachment to the surface. Pseudomonas proteins related to surface and cell attachments were observed in N2-fixing biofilms in particular. Furthermore, co-localized biofilm cells displayed a resilient response to extra shear forces induced by segmented media/air flows. This study highlights the role of Pseudomonas in the initial attachment process, as well as the effects of different nitrogen-feeding strategies and operation regimes on biofilm composition and growth. IMPORTANCE Cyanobacteria are highly interesting microorganisms due to their ability to synthesize sugars from CO2 while using water and sunlight as electron and energy sources. Further, many species are also capable of utilizing molecular nitrogen, making them independent of artificial fertilizers. In this study, such organisms are cultivated in a technical system, which enables them to attach to the reactor surface, and form three-dimensional structures termed biofilms. Biofilms achieve extraordinarily high cell densities. Furthermore, this growth format allows for continuous processing, both being essential features in biotechnological process development. Understanding biofilm growth and the influence technical settings and media composition have on biofilm maturation and stability are crucial for reaction and reactor design. These findings will help to open up these fascinating organisms for applications as sustainable, resource-efficient industrial workhorses.

A Coaxial Pulsed Plasma Thruster Model with Efficient Flyback Converter Approaches for Small Satellites

Pulsed plasma thrusters (PPT) have demonstrated enormous potential since the 1960s. One major shortcoming is their low thrust efficiency, typically <30%. Most of these losses are due to joule heating, while some can be attributed to poor efficiency of the power processing units (PPUs). We model PPTs to improve their efficiency, by exploring the use of power electronic topologies to enhance the power conversion efficiency from the DC source to the thruster head. Different control approaches are considered, starting off with the basic approach of a fixed frequency flyback converter. Then, the more advanced critical conduction mode (CrCM) flyback, as well as other optimized solutions using commercial off-the-shelf (COTS) components, are presented. Variations of these flyback converters are studied under different control regimes, such as zero voltage switching (ZVS), valley voltage switching (VVS), and hard switched, to enhance the performance and efficiency of the PPU. We compare the max voltage, charge time, and the overall power conversion efficiency for different operating regimes. Our analytical results show that a more dynamic control regime can result in fewer losses and enhanced performance, offering an improved power conversion efficiency for PPUs used with PPTs. An efficiency of 86% was achieved using the variable frequency approach. This work has narrowed the possible PPU options through analytical analysis and has therefore identified a strategic approach for future investigations. In addition, a new low-power coaxial micro-thruster model using equivalent circuit model elements is developed.This is referred to as the Carlow–Stuttgart model and has been validated against experimental data from vacuum chamber tests in Stuttgart’s Pulsed Plasma Laboratory. This work serves as a valuable precursor towards the implementation of highly optimized PPU designs for efficient PPT thrusters for the next PETRUS (pulsed electrothermal thruster for the University of Stuttgart) missions.

Self-Starting Soliton–Comb Regimes in χ(2) Microresonators

The discovery of stable and broad frequency combs in monochromatically pumped high-Q optical Kerr microresonators caused by the generation of temporal solitons can be regarded as one of the major breakthroughs in nonlinear optics during the last two decades. The transfer of the soliton–comb concept to χ(2) microresonators promises lowering of the pump power, new operation regimes, and entering of new spectral ranges; scientifically, it is a big challenge. Here we represent an overview of stable and accessible soliton–comb regimes in monochromatically pumped χ(2) microresonators discovered during the last several years. The main stress is made on lithium niobate-based resonators. This overview pretends to be rather simple, complete, and comprehensive: it incorporates the main factors affecting the soliton–comb generation, such as the choice of the pumping scheme (pumping to the first or second harmonic), the choice of the phase matching scheme (natural or artificial), the effects of the temporal walk off and dispersion coefficients, and also the influence of frequency detunings and Q-factors. Most of the discovered nonlinear regimes are self-starting—they can be accessed from noise upon a not very abrupt increase in the pump power. The soliton–comb generation scenarios are not universal—they can be realized only under proper combinations of the above-mentioned factors. We indicate what kind of restrictions on the experimental conditions have to be imposed to obtain the soliton–comb generation.

Loss Modeling of Large Hydrogenerators for Cost Estimation of Reactive Power Services and Identification of Optimal Operation

As a result of the worldwide energy transition, reactive power generation has started to become a more scarce resource in the power grid. Until recently, reactive power has been an auxiliary grid service that classical power generation facilities have provided without necessarily allocating any cost for this valuable service. In this paper, a new approach for predicting the additional costs of reactive power services delivered by large hydrogenerators is proposed. We derive the optimal reactive power (ORP) with minimal losses as a function of the active power level within the generator's capability diagram. This pathway can then be used to calculate additional losses from operational regimes deviating from the ORP. To back up the analysis, a dedicated example study was handpicked consisting of four real-world generators scaled in terms of power rating, i.e., 15MVA, 47MVA, 103MVA, and 160MVA. The objective was to identify how the ORP scale from smaller to larger MVAsized generators. Moreover, a sensitivity analysis of the machine characteristics is conducted. We find the ratio between the rotor and stator losses as the determining factor. Finally, we show how our framework could justify profit for reactive power services, which are projected to increase in the future.

Cosserat Rod Modeling of Continuum Robots from Newtonian and Lagrangian Perspectives

Cosserat rod theory proved efficient modeling performances in robotics, especially in the context of continuum robots, in the past decade. The implementation of such theory is far from being unique and straightforward. We consider the illustrative example of multisegment, general routing tendon actuated continuum robots in their nominal static operating regime. This article details two main approaches based on Cosserat rod modeling, namely, the Newtonian and Lagrangian approaches. We provide a walk-through guide regarding theoretical derivations and numerical implementation of both approaches, together with a proof of equivalence. This comparative study is supplemented with novel contributions and extensions of each approach and in-depth discussion of their performances and applicability, as well as highlighting their special features.

Linear theory of micropolar media with internal nonlocal potential interactions

AbstractThis paper proposes a mathematical model that can be used to quantify the effects of a polarized electric field on the mechanical properties of a polar dielectric in the framework of mechanics of deformable solids. The physical essence of the phenomenon is known. However, its direct use in practical calculations may cause difficulties due to the complexity of the composition and structure of materials used in the design and manufacture of specific products whose operation regimes are based on polarization effects. A continuum description of the polarization phenomenon makes it possible to circumvent these difficulties.The basis of the generalized model is a micropolar linearly elastic medium. The generalization consists in taking into account the initial stress state of the material, as well as cross effects under the mutual influence of translational and rotational deformations, the possibility to calculate the characteristics of micropolar material properties based on a special nonlocal model of micropolar media with internal nonlocal potential interactions. It takes into account translational and rotational potential interactions of particles of a continuous medium at finite distances. The kinematic characteristics of the material are the same as those used by the traditional model of a micropolar elastic medium ‐ the gradients of translational displacements of the medium's particles, their rotations independent of the medium's rotation and rotations of the particles relative to the medium. Generalized forces performing work on these generalized displacements are volumetrically and surface‐distributed forces and moments. To determine the values of the parameters of the interparticle potentials of the nonlocal model, a method is proposed using data from experiments to determine the material constants of isotropic linearly elastic materials and the dispersion law for plane acoustic waves of high frequency. The paper considers and quantifies the effects of anisotropy in an initially isotropic material, as well as anharmonic effects that cause dielectric heating by a periodically changing polarizing field. The results are compared qualitatively and quantitatively with known experimental data and physical notions of the phenomena in question.

Stochastic Performance of Journal Bearing With Two-Layered Porous Bush—A Machine Learning Approach

Abstract This investigation presents the deterministic and stochastic responses of the journal bearing with a two-layered porous bush. Pressure equations in the porous layers and modified Reynolds equations in the clearance region are governed by the finite difference method (FDM). Stochastic analysis based on Monte Carlo simulation (MCS) is used to investigate the effect of random variation in input parameters caused by uncertain operating conditions, improper installations, and manufacturing imperfections. In order to enhance computational efficiency, this probabilistic study is conducted in conjunction with the machine learning (ML) model based on the support vector machine (SVM) algorithm. The uncertainty in the bearing responses is presented in the form of the probability density function (PDF), considering both the independent and combined effect of the stochastically varied input parameters. Graphical illustration of the data-driven sensitivity represents the relative significance of each input parameter affecting the steady-state responses of the journal bearing with two-layered porous bush. The findings of the present study reveal that the stochastic variations in the input parameters have a profound influence on the operational characteristics of the porous bearing. The outcome of the present study will be helpful in deciding the operational regime of the porous bearing under the practically relevant stochastic environment.

Effectuating tunable valley selection via multiterminal monolayer graphene devices

Valleytronics using two-dimensional materials opens unprecedented opportunities for information processing using a valley polarizer as a basic building block. Various methodologies, such as strain engineering, the inclusion of line defects, and the application of static magnetic fields, have been widely explored for creating valley polarization. However, these methods suffer from low transmission or lack of polarization directionality. To overcome the above limitations, we propose an all-electrical valley polarizer using zigzag edge graphene nanoribbons in a multiterminal device geometry. The proposed device can be gate-tuned to operate along two independent regimes: (i) a terminal-specific valley filter that utilizes band-structure engineering, and (ii) a parity-specific valley filter that exploits the parity selection rule in zigzag edge graphene. We show that the device exhibits intriguing physics in the multimode regime of operation affecting the valley polarization; we investigate various factors influencing polarization in wide-device geometries, such as optical analogs of graphene Dirac fermions, angle-selective transmission via $p\ensuremath{-}n$ junctions, and the localization of edge states. Furthermore, we evaluate the performance of the proposed device structures in the presence of Anderson short-range disorder at the edges and the bulk, and we find it to be resilient to edge disorder even for a higher disorder strength. The device geometry is optimized to achieve maximum valley polarization, thereby paving the way for a physics-based tunable valleytronic device.

Design, fabrication, and investigations of prototype supersonic micro-ejector for innovative cooling system of electronic components

Innovative approach for electronics cooling was proposed, i.e. heat generated by a part of electronic equipment, e.g. CPU, is absorbed by heat driven micro-ejector refrigeration system that can provide cooling of other electronic components, e.g. GPU. It was demonstrated the procedure of design, fabrication, and experimentation on the supersonic micro-ejectors for the case of isobutane as a working fluid for such system. It was demonstrated that it possible to design and fabricate the micro-ejector of cooling capacity in the range 3 W suitable for cooling of electronic equipment. For the discussed micro-ejector entrainment ratio obtained was app. 0.20 under conditions of the motive heat source temperature app. 60 °C and evaporation temperature app. 22 °C. There were demonstrated difficulties in fabrication of the supersonic ejector due to small dimensions of the motive nozzle as well as mixing chamber. Required throat diameter of the motive nozzle was less than 200 μm and the diameter of the mixing chamber was 260 μm. For reported tests conditions the boundary temperature of the on-design operation condition was between 21 – 25 °C. However, the operation of the micro-ejector under off-design operation regime was stable and repeatable. Micro-ejector tests required an indirect method of measurement of critical motive mass flow rate to be applied. The performance line of tested ejector fits to ejectors theory and meet the basic assumptions in terms of thermal capacity and operating temperature. CFD technique used for numerical predictions of the ejector performance fits to experimental measured values with acceptable accuracy.

Highly Sensitive Detection of Urea Using Si Electrolyte-Gated Transistor with Low Power Consumption.

We experimentally demonstrate Si-based electrolyte-gated transistors (EGTs) for detecting urea. The top-down-fabricated device exhibited excellent intrinsic characteristics, including a low subthreshold swing (SS) (~80 mV/dec) and a high on/off current ratio (~107). The sensitivity, which varied depending on the operation regime, was analyzed with the urea concentrations ranging from 0.1 to 316 mM. The current-related response could be enhanced by reducing the SS of the devices, whereas the voltage-related response remained relatively constant. The urea sensitivity in the subthreshold regime was as high as 1.9 dec/pUrea, four times higher than the reported value. The extracted power consumption of 0.3 nW was extremely low compared to other FET-type sensors.

Effect of nitric oxide on the performance and emissions of a hydrogen-fueled HCCI engine

Homogeneous charge compression ignition (HCCI) engines have historically generated interest due to its potential to achieve high efficiency and low emissions. This paper presents an experimental investigation of hydrogen port fuel injection in a modified Cooperative Fuel Research (CFR) engine operated under HCCI conditions. The effect of adding nitric oxide (NO) to the intake air on engine performance, emissions, and combustion characteristics was investigated at various inlet temperatures. The experiments considered the operating regime and limitations for hydrogen HCCI engines with and without NO addition. The engine can operate over a wide range of air–fuel ratios i.e., λ = 2.7 to 4.0 at 150 OC inlet air temperature without NO addition.NO also acts as a knock promoter in reciprocating engines, limiting the engine's output. The results indicate that adding NO significantly promotes the auto-ignition of the hydrogen-air mixture, thereby extending the engine's operable range, and an ultra-lean λ of 5.0 can be reached. Our findings indicate that NO has the most notable effect on engine performance at an inlet air temperature of 90 OC. Furthermore, the results show that the addition of NO increases the amount of NOx emissions in the exhaust gas; about 50 ppm of NO was converted into NO2 during the combustion process. Adding NO to the hydrogen-air mixture has the potential to extend the engine's range of operation in HCCI providing a promising avenue for further research into HCCI combustion engines and the potential to improve efficiency.

Targeting operational regimes of interest in recurrent neural networks.

Neural computations emerge from local recurrent neural circuits or computational units such as cortical columns that comprise hundreds to a few thousand neurons. Continuous progress in connectomics, electrophysiology, and calcium imaging require tractable spiking network models that can consistently incorporate new information about the network structure and reproduce the recorded neural activity features. However, for spiking networks, it is challenging to predict which connectivity configurations and neural properties can generate fundamental operational states and specific experimentally reported nonlinear cortical computations. Theoretical descriptions for the computational state of cortical spiking circuits are diverse, including the balanced state where excitatory and inhibitory inputs balance almost perfectly or the inhibition stabilized state (ISN) where the excitatory part of the circuit is unstable. It remains an open question whether these states can co-exist with experimentally reported nonlinear computations and whether they can be recovered in biologically realistic implementations of spiking networks. Here, we show how to identify spiking network connectivity patterns underlying diverse nonlinear computations such as XOR, bistability, inhibitory stabilization, supersaturation, and persistent activity. We establish a mapping between the stabilized supralinear network (SSN) and spiking activity which allows us to pinpoint the location in parameter space where these activity regimes occur. Notably, we find that biologically-sized spiking networks can have irregular asynchronous activity that does not require strong excitation-inhibition balance or large feedforward input and we show that the dynamic firing rate trajectories in spiking networks can be precisely targeted without error-driven training algorithms.

Design and Fabrication of Single-Mode Multi-Junction 905 nm VCSEL With Integrated Anti-Phase Mode Filter

In this paper, a record-high single-mode output power from a multi-junction vertical-cavity surface emitting laser (VCSEL) emitting at 905nm is achieved. Single spectral mode emission of the VCSEL is realized by using an anti-phase mode filter, placed at the top surface of the device, that acts as a relief layer to suppress the higher order transverse modes. Placement of such anti-phase layer at the surface areas in which the higher order modes are expected to emit, leads to reduction in the effective mirror reflectivity at those areas, increased optical losses, and consequently, increased threshold gain for the higher order modes compared to the fundamental mode. The room-temperature light-current-voltage characteristics of a 6-junction 905nm VCSEL with an oxide aperture size of ∼8μm and mode filter size of 5μm shows a single-mode optical power of 12.55mW and maximum power conversion efficiency of 56.48%. Moreover, the emission spectrum of this device shows a stable side-mode suppression ration of >30dB in the single-mode operation regime. The VCSEL remains reliably single-mode at higher temperatures, generating a maximum optical output power of 9.48mW at 60°C. Such remarkable single-mode performance can be mainly attributed to the multi-junction epitaxial structure of the device, in which the output optical power is expected to proportionally increase according to the number of bipolar cascade active regions.

Mission Concept and Development of the First Interstellar CubeSat Powered by Solar Sailing Technology

Project Svarog is a student-led initiative aiming to reach the heliopause using a solar sail. Orbital models have proven the feasibility of the mission given the mass-to-area ratio of about 9 grams per square meter of the sail for a satellite launched on a piggyback mission to Mars. Solar sailing increases the flexibility of missions to the outer Solar System, as unique planet alignment, which was crucial for gravity assists is no longer required. Long-term missions require a better understanding of thin membrane behaviour since buckling of sail material under solar radiation pressure might cause the spacecraft to tumble unpredictably. Reduced order model of membrane deflection is thus coupled with orbital simulation, resulting in the determination of the operation regime, for which the mission escapes the Solar System. Additionally, vacuum chamber experiments designed to investigate the effects of solar radiation pressure and heating on the transient and steady-state behaviour of the sail have been devised. The system is designed to be built as a 6U CubeSat, being one of the first missions to utilise small-scale platforms for deep space missions. Granted that the first mission is successful, the Svarog system could also serve as a low-cost testbed for new technologies and research opportunities in deep space. Keywords: Satellite, Deep Space, CubeSat, Solar Sail, Orbital Mechanics, Structural Design

Dual Regime Mode-Locked and Q-Switched Erbium-Doped Fiber Laser by Employing Graphene Filament-Chitin Film-Based Passive Saturable Absorber.

We investigate the dynamics of high energy dual regime unidirectional Erbium-doped fiber laser in ring cavity, which is passively Q-switched and mode-locked through the use of an environmentally friendly graphene filament-chitin film-based saturable absorber. The graphene-chitin passive saturable absorber allows the option for different operating regimes of the laser by simple adjustment of the input pump power, yielding, simultaneously, highly stable and high energy Q-switched pulses at 82.08 nJ and 1.08 ps mode-locked pulses. The finding can have applications in a multitude of fields due to its versatility and the regime of operation that is on demand.

Power System Stabilizer Design using Genetic Algorithms and Particle Swarm Optimization

in this paper, Meta-heuristic techniques using genetic algorithms GA and particle swarm optimization PSO to tuning optimal design of power system stabilizer PSS proposed. This latter have been used for many years to add damping to electromechanical oscillations of power system, Based on this idea we have proposed multiobjective function composed with tow function, first maximize stability margin by increasing the damping factors while minimizing the real parts of the eigenvalues. Simulation results to comparative study between genetic algorithms and particle swarm optimization obtained by our realized graphical user interface (GUI) proved the efficiency of PSS optimized by genetic algorithms in comparison with Particle Swarm Optimization, showing stable system responses almost insensitive to large parameter variations and under different operating regime (under-excited, nominal and over excited regime).

Fundamental and applied investigations of the liquid-metal cooled fast reactor thermal hydraulics (achieved results and further investigation issues)

The results of experimental and computational-theoretical investigations in the area of hydrodynamics and heat transfer of fast reactors and accelerator-driven system with liquid metal coolants are presented, and the problems and tasks for further investigations are formulated. Physical phenomena, effects, laws and process characteristics occurring in reactor power plants, including a flow path and a fast reactor core: the velocity and temperature fields, the structure and characteristics of turbulent transfer of momentum and energy, the hydraulic resistance of channels and fuel rod assemblies, the collector system hydrodynamics, the vibroacoustics, the heat transfer in channels and fuel rod assemblies with liquid metal cooling and inter-channel exchange are considered and analyzed. The data of experimental investigations are presented on a single-tube model of a large-module steam generator and on a fragmentary thermohydraulic model of a steam generator of a reactor power plant with twisted steam-generating tubes operating at subcritical and supercritical water pressure. The results of investigations of temperature and velocity fields on a small-scale water model of a fast reactor vessel with an integral layout in nominal, transient and emergency operating regimes are demonstrated. The investigation results on model of a fast reactor vessel with an integral layout are demonstrated that the effect of thermogravitational forces leads to temperature stratification with stagnant and recirculating formations, internal waves appear at the stratified boundaries, temperature pulsations, thermal fatigue of structural materials and a decrease in the service life of the equipment. It is shown that the liquid metal boiling process in fuel rod assemblies is formed under the influence of various factors, has a complex structure, is characterized by both stable (nucleate, annular-dispersed) and pulsation (slug) regimes with significant fluctuations of technological parameters, which can cause a crisis of heat transfer. Heat transfer was studied, a cartogram two-phase flow was obtained for liquid metal boiling in fuel rod assemblies, the effect of the surface roughness of fuel rods on liquid metal heat transfer and boiling regimes in fuel rod assemblies was found. The possibility of long-term stable cooling of the core during sodium boiling was shown by using “sodium cavity” over the reactor core. The kinetic and mechanical characteristics of the degradation process of the simulated fuel assembly in fast reactor core during the thermal interaction of the uranium-containing simulators of fuel with static sodium and their dependence on the parameters and design system were determined.Information about the key problems of thermophysical investigations of a high-temperature fast reactor with a sodium coolant for the production of hydrogen and reactors cooled by water at supercritical pressure is given.

Spatial-Temporal Modeling and Analysis of Reliability and Delay in Urban V2X Networks

The fifth-generation (5 G) based vehicle-to-everything (V2X) communication is a promising technology to enhance both manned and unmanned driving systems. To this end, the 5 G V2X networks should satisfy stringent requirements on transmission reliability and delay for exchanging safety-critical messages (SCMs). A joint analysis of transmission reliability and delay in V2X communication networks is thus crucial, particularly in urban 5 G V2X networks. This was considered prohibitive due to the complicated spatial-temporal dynamics of V2X communications caused by interference, channel fading, as well as queueing and retransmission of SCMs. Moreover, urban 5 G V2X networks are typically deployed in a finite area, where locations of nodes are spatially correlated and cannot be conveniently modeled as Poisson point process (PPP). In this paper, we propose a novel binomial point process (BPP) based analytic framework for modeling the spatial-temporal dynamics of urban 5 G V2X communications and characterizing transmission reliability and delay of SCM exchange jointly. The presented framework captures not only the spatial distribution of interference and channel fading during uplink and downlink transmissions, but also the temporal dynamics associated with queueing and retransmissions of SCMs. Exploiting the stochastic geometry theory and queueing theory, closed-form expressions of transmission reliability and delay are derived, which are further validated using Monte Carlo simulations. Both the numerical and simulation results reveal complicated couplings between the transmission reliability and delay in different operation regimes. Nevertheless, the proposed analytical framework can accurately capture the reliability-delay relations.

Coupling the COST reference plasma jet to a microfluidic device: a new diagnostic tool for plasma-liquid interactions

Plasma-liquid interaction processes are central to plasma applications in medicine, environment, and material processing. However, a standardized platform that allows the study of the production and transport of plasma-generated reactive species from the plasma to the liquid is lacking. We hypothesize that use of microfluidic devices would unlock many possibilities to investigate the transport of reactive species in plasma-treated liquids and, ultimately, to measure the effects of these species on biological systems, as microfluidics has already provided multiple solutions in medical treatment investigations. Our approach combines a capacitively coupled RF plasma jet known as the COST reference plasma jet with simple 3D printed microfluidic devices. This novel pairing is achieved by carefully controlling capillary effects within the microfluidic device at the plasma-liquid interaction zone. The generation and transport of reactive species from the plasma to the liquid inside the microfluidic device are analyzed using a colorimetric hydrogen peroxide concentration assay. A capillary flow model is provided to explain the two main regimes of operations observed in the device and their merits are discussed. Overall, the proposed plasma-microfluidic prototype shows great potential for the fundamental study of plasma-liquid interactions and opens the way to the use of standard microfluidic devices with plasma sources developing a plasma column or a plasma plume.