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Hydrogen ejectors effectively utilize excess unreacted hydrogen. However, traditional ejectors have limited operational ranges and are only suitable for specific power ranges. This paper presents a dual-nozzle ejector aimed at broadening its operational range through different working modes. A simulation model, validated by experiments, is employed based on the working principles of ejectors. Spiral blades are installed at drive end to improve the recirculation efficiency. Flow characteristics, including streamwise and spanwise vortices at high power, are also investigated in different modes. Results indicate that optimal operating range for Ring-nozzle(RN) mode is between 31.1 and 124.4A. When output current exceeds 124.4A, it is necessary to switch to Central-nozzle (CN) or Double-nozzles (DNs) mode. Analysis of streamlines and velocity vectors reveals that installing spiral blades can modify directions of primary flow. Blades with appropriate distortion should be selected. In CN mode, when stack reaches 60% of rated power, installing 20° spiral blades has a minimal impact on stability of radial flow. Installing 30° or 40° spiral blades is suitable for full-load condition. In DNs mode, installing 30° spiral blades enhances acceleration of gas flow with lower influence from radial influx. This ejector provides assurance for upgrade of fuel cell stacks by incorporating recirculation technology. • A dual-nozzle ejector with spiral guide blades is designed, verified and evaluated. • Installed spiral blades change direction and gather kinetic energy of primary flow. • Advantageous working conditions of different modes with blades are discussed. • Flow mechanism of different blades under high power in two modes is analyzed. • Flow acceleration and losses should be balanced by changing the twist of blades. [ABSTRACT FROM AUTHOR]

Multi-principal element alloys (MPEAs) exhibit outstanding strength attributed to the complex dislocation dynamics as compared to conventional alloys. Here, we develop an atomic-lattice-distortion-dependent discrete dislocation dynamics framework consisted of random field theory and phenomenological dislocation model to investigate the fundamental deformation mechanism underlying massive dislocation motions in body-centered cubic MPEA. Amazingly, the turbulence of dislocation speed is identified in light of strong heterogeneous lattice strain field caused by short-range ordering. Importantly, the vortex from dislocation flow turbulence not only acts as an effective source to initiate dislocation multiplication but also induces the strong local pinning trap to block dislocation movement, thus breaking the strength-ductility trade-off. [ABSTRACT FROM AUTHOR]

The objectives of this paper are to pursue an accurate numerical method of unsteady cavitating flow at a reasonable calculation cost and investigate the unsteady cavitating flow characteristics of a centrifugal pump. Firstly, the cavitating flow simulations of a centrifugal pump were performed using the partially-averaged Navier–Stokes (PANS) turbulence model and its improved model to evaluate the numerical methods based on experimental data. Compared with the experimental results, the improved PANS turbulence model can better predict the cavitating flows in the pump and has better applicability. Further, the unsteady cavitating flow characteristics of the centrifugal pump, such as the vapour volume fraction, the cavitation-vortex dynamics and the pressure and head fluctuations, were simulated by improved PANS model and discussed. The liquid flow vortex at the end of the cavitation in the impeller is an important reason for the periodic change of the cavitation shape. The periodic change of cavity volume has a certain impact on the pressure pulsation in the impeller and the pump head. [ABSTRACT FROM AUTHOR]

Objectives: Blood‐flow pattern is an essential factor in cardiovascular development. Recently, blood speckle‐tracking echocardiography (BST) based on high‐frame‐rate ultrasound has emerged as a promising technique for the assessment of blood‐flow patterns and properties. The objectives of this study were to determine the feasibility of BST in the fetus and to assess intracardiac blood‐flow patterns of fetuses with a congenital heart defect (CHD) using this technique. Methods: This was a prospective study consisting of 35 normal fetuses, 35 fetuses with left‐sided obstructive lesion (LSOL) and 35 fetuses with right‐sided obstructive lesion (RSOL). BST images of fetal intracardiac regions of interest (ROIs), including the left ventricle (LV), right ventricle (RV), ascending aorta (AAo), aortic arch (AA), descending aorta (DAo) and pulmonary artery (PA), were obtained and analyzed. The feasibility of BST was assessed, and blood‐flow pattern and number of vortices in the ROIs were recorded. Results: The median gestational age of the fetuses was 24.7 weeks (range, 19.6–34.3 weeks). BST was feasible in 81.6% of cases, and the cut‐off value of depth for an adequate BST image was ≤ 7.9 cm. There were no differences in the presence of vortex/turbulent blood flow in the LV or RV among the three groups. Vortex/turbulent blood flow in the AAo was detected in 0% (0/35), 14.3% (5/35) and 57.1% (20/35) of cases in the control, LSOL and RSOL groups, respectively. The respective values were 5.7% (2/35), 14.3% (5/35) and 51.4% (18/35) for the AA; 0% (0/35), 48.6% (17/35) and 0% (0/35) for the DAo; and 0% (0/35), 40.0% (14/35) and 51.4% (18/35) for the PA. With the exception of the DAo in the RSOL group, vortex/turbulent flow in the great artery ROIs was significantly more common in the LSOL and RSOL groups than in controls (P < 0.01). In the LSOL group, the number of vortices in the AAo, AA, DAo and PA was significantly greater compared with that in controls (P < 0.01). In the RSOL group, the number of vortices in the LV, AAo, AA and PA was significantly greater compared with that in controls (P < 0.01). Conclusions: Fetuses with CHD were more likely to exhibit vortex/turbulent blood flow and increased number of vortices in the great arteries compared with healthy controls. Further research is needed to determine the biomechanical effect of blood‐flow patterns, especially vortex flow, on fetal cardiovascular structure and function. © 2023 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

The evolution of unforced and weakly damped two-dimensional turbulence over random rough topography presents two extreme states. If the initial kinetic energy E is sufficiently high, then the topography is a weak perturbation, and evolution is determined by the spontaneous formation and mutual interaction of coherent axisymmetric vortices. High-energy vortices roam throughout the domain and mix the background potential vorticity (PV) to homogeneity, i.e., in the region between vortices, which is most of the domain, the relative vorticity largely cancels the topographic PV. If E is low, then vortices still form but they soon become locked to topographic features: Anticyclones sit above topographic depressions and cyclones above elevated regions. In the low-energy case, with topographically locked vortices, the background PV retains some spatial variation. We develop a unified framework of topographic turbulence spanning these two extreme states of low and high energy. A main organizing concept is that PV homogenization demands a particular kinetic energy level E#. E# is the separator between high-energy evolution and low-energy evolution. [ABSTRACT FROM AUTHOR]

In order to improve the yield of steel produced in the converter and the quality of the molten steel, and to understand the distribution of the flow field in the converter and ladle during the steelmaking process, the CFD fluid simulation software Fluent 2020 R2 was used to analyze the flow field of the converter static steelmaking process. The aperture of the steel outlet and the timing of the vortex formation under different angles were studied, as well as the disturbance level of the injection flow in the ladle molten pool. The study revealed that in the steelmaking process, the emergence of tangential vectors caused the entrainment of slag by the vortex, whereas in the later stages of steelmaking, the turbulent flow of slag disrupted the vortex, resulting in its dissipation. When the converter angle increases to 90°, 95°, 100°, and 105°, the eddy current occurrence time is 43.55 s, 66.44 s, 68.80 s, and 72.30 s, and the eddy current stabilization time is 54.10 s, 70.36 s, 70.95 s, and 74.26 s, respectively. When the converter angle is 100–105°, it is suitable to add alloy particles into the ladle molten pool. When the tapping port diameter is 220 mm, the eddy current inside the converter changes and the mass flow rate of the tapping port is "oscillating". When the aperture of the steel outlet was 210 mm, the steelmaking time could be shortened by about 6 s without affecting the internal flow field structure of the converter. [ABSTRACT FROM AUTHOR]

This study aims to investigate the impact of cavitation states on the stability of cryogenic pumps. Steady and unsteady simulations of the internal flow were conducted based on an SST k–ω turbulence model and a modified Zwart cavitation model considering thermodynamic effects. The modified cavitation model was verified using the hydrofoil model and compared with the Hord test results. The results indicate that the variation in pressure at the pump inlet has a significant influence on the cavitation in the pump. The cavitation states and fluid flow directions vary across the different spans in the impeller channel. The smaller the distance from the front cover of the impeller, the more severe is the cavitation, in addition to the appearance of a vortex. The influence of the formation of a longitudinal vortex at the impeller outlet on the pressure fluctuation in the cavitation state was revealed. The rotation of the impeller has negligible influence on the pressure load distribution at the blade inlet. However, it has a higher influence on that of the second half of the blade, particularly when the blade passes through the volute tongue. Cavitation can exacerbate the instability of pump operation. The research results are significant for accurately predicting cavitation performance and improving the anti-cavitation capability of cryogenic pumps. [ABSTRACT FROM AUTHOR]

The Liutex vector is new quantity introduced to represent the rigid-body rotation part of fluid motion and thus to define and identify vortices in various flows. In this work, the intermittency and power-law similarity of the Liutex vector in homogeneous, isotropic turbulence and a turbulent channel are explored. First, we found that the Liutex vector is more intermittent than the vorticity vector in the considered turbulent flows, which indicates that an iso-surface of a Liutex magnitude with an appropriate threshold could capture the major rotating motions or vortical motions of the flow. Second, the three-dimensional energy spectrums of velocity, vorticity (enstrophy spectrum) and the Liutex vector in homogeneous isotropic turbulence are shown to exhibit power laws of −5/3, 1/3 and 1/3 in the inertial subrange, respectively, whilst the Liutex energy spectrum particularly satisfies an additional −10/3 power law in the viscous subrange. This viscous similarity of the Liutex vector is the only power law that survived from the wall presence and is argued to originate from the fact that the Liutex vector represents the rigid part of fluid motion and is free from any shear contamination. The existence of such a viscous similarity law indicates a certain coherence of the small scales of turbulence and could possibly help understand and model turbulence. [ABSTRACT FROM AUTHOR]

Heat transport in rotating processes finds a wide range of application in which academic issues in the fluid mechanics and heat transfer areas are here reported. This paper discusses successive works from the seminal paper of Taylor (1923) to recent numerical results established from a broad range of methods such as DNS, LES, RANS or LB methods. The flow regimes identification is thus reported in Taylor–Couette geometry. The role of the axial flow rates in the apparition, stabilization and destruction of the large-scale of the turbulent structures is depicted in the case of Taylor–Couette–Poiseuille geometry. In a non-isothermal condition, a discussion is held on the various exponent values found in the scaling relationships relying on the Nusselt number as a function of the Rayleigh or Reynolds numbers according to the regimes of thermal convection. [ABSTRACT FROM AUTHOR]

A numerical study of the aerodynamics of a swirling turbulent flow and of the classification of particles in the vortex chamber of a pneumatic combined apparatus has been performed. The obtained results indicate the possibility of achieving a uniform distribution of the radial flow velocity along the height of the chamber in the particle separation zone in it by changing the shape of the rotor blades of the apparatus, which is a prerequisite for its efficient operation. The trajectories of motion of single particles in the vortex chamber are determined. A significant effect of turbulent flow pulsations on the efficiency of particle separation in it has been established. The reliability of the obtained results is confirmed by test studies and by their comparison with experimental data. [ABSTRACT FROM AUTHOR]

This research present an analysis of the decomposition of Laguerre-Gaussian modes into Hermite-Gaussian modes when propagating through turbulence. This effect can be clearly observed by canceling the original Laguerre-Gaussian beam with another of different topological charge. The results of the propagations of these beams through Kolmogorov turbulence phase masks were analyzed, identifying which ones achieved the decomposition. The turbulences were then decomposed into the first 15 Zernike polynomials and used as new 'Zernike turbulences'. We show that the turbulence internal process that allows the decomposition has a high correlation with a phase distortion based on a single Zernike polynomial or a combination of them. [ABSTRACT FROM AUTHOR]

Flows in river habitats are characterized by unsteady turbulence due to the existence of woody debris, boulders and vegetation. As a representative aquatic species, fish is important for the riverine ecosystems, with its complex behavioural responses to turbulent flows. Previous studies investigated the fish–vortices interaction with vortex streets by placing objects with simplified geometries centred at the flow. Nonetheless, complex river morphology in natural rivers results in much more spatially heterogeneous flows due to randomly distributed obstructions. Thus, a semi‐circular cylinder patch located on one side of the flume is used to mimic a vegetation patch at the riverbank. The patch varies in diameter (D0 = 16, 20 and 24 cm) and density (φ = 0.04 and 0.1), whereas the flow velocity is fixed at 25 cm s−1. Fish are observed to swim in three typical patterns, which are "swim around" (pattern 1), "spill" (pattern 2) and "swim through" (pattern 3). For flow with a dense patch, all three patterns are recorded, but only patterns 1 and 2 are observed in sparse patches. It is noticed that in patterns 1 and 2, fish prefer to hold place in zones of low velocity and low turbulence. Moreover, variations in patch diameter have little influence on pattern selection. Results showed that tail beat amplitude (TBA*) in each zone displayed more variations compared with tail beat frequency (TBF). In addition, Spearman's rank tests revealed that TBA* is affected by none of the four hydrodynamic variables (U,ustd,τxy,Ωz), whereas flow velocity imposes the most influence on TBF. Both diameter and density of the patch displayed no significant influence on TBA* and TBF. [ABSTRACT FROM AUTHOR]

In study, flow structures around buildings placed triple-diagonal and 7.5 cm and 10 cm distances between buildings with dimensions of 5cmx5cmx5cm without roof were investigated as experimental by using Particle Image Velocimetry (PIV) technique. Besides, flow analysis vicinity one building without roof as numerical with ANSYS Fluent program having steady, three dimensional, k-ε turbulence model was done and the attained results were matched with these of experimental. In the work, distributions of streamline <ψ> and velocity vectors were drawn and average equivalent velocity curves were researched for different distances between buildings. It was determined that jet flow region fairly enlarged at 10 cm distance according to distance of 7.5 cm and flow separation area around building placed as diagonal shrank. However, it was found that there is at most a 3% differences between experimental and numerical results. [ABSTRACT FROM AUTHOR]

In this paper, the effects of regular waves propagating against the current on the wake of a wide bathymetric obstacle are experimentally investigated. For that purpose, a square cylinder of height representing 1 / 8 t h of the water column, mounted perpendicular to the flow, is used. Both Reynolds and Froude numbers are close to the ones encountered at sea and swell properties (amplitude, frequency and wavelength) which are typical conditions in the English Channel. To study this complex hydrodynamic interaction, PIV measurements are used to capture the velocity field around and in the wake of the cylinder. The wake of this wide cylinder has been extensively studied and is characterised by its direction towards the water surface and by energetic and wide vortices arising from the sheared layer at a Strouhal number of approximatively 0.06, after a merging of smaller eddies. In this work, the focus is on how surface gravity waves, propagating against the current, modify the generation of these turbulent structures. The results show that the cylinder wake is strongly modified in the presence of waves, even if, on average, the main wake structure is globally conserved. The waves act both on the vortex generation and the wake development with modifications in terms of turbulent energy distribution and level, wake recovery and ascent rate. The vortex shedding becomes highly energetic and well-organised from the cylinder position. Its return period is extremely regular and corresponds to half of the wave frequency which is really close to the natural vortex shedding frequency. That results in a doubling of the statistical length scale of the vortices. • Swell induced-motion effects on high and isolated bathymetry roughness. • Bottom mounted cylinder wake characterisation in presence of waves opposing current. • Vortex generation and dynamic study. • Energy transfer between wave and vortex shedding frequency in the near-wake. [ABSTRACT FROM AUTHOR]

With the increasing application of bidirectional axial pump, it is necessary to study the flow and cavitation characteristics of bidirectional pump. In this paper, the cavitation and flow characteristics of the tip clearance under different clearances and different cavitation numbers of the S-hydrofoil bidirectional axial flow pump were studied by combining experimental and numerical simulation methods under reverse operation conditions. The section of the bidirectional pump was experimentally studied by high-speed photography and pressure pulsation. Based on the method of RANS, the SST-CC turbulence model and ZGB cavitation model were used to simulate the clearance cavitation of the bidirectional pump, and the cavitation morphology, velocity distribution, clearance vortex structure and energy distribution of blade tip clearance were investigated. The study reveals the flow characteristics of the clearance flow field of the bidirectional pump, and provides reference for the design and operation of it. • Deep cavitation bidirectional pump gap tail will form reverse shear cavitation. • Special distribution of S-shaped hydrofoil gap velocity will form a variety of vortices. • More disorderly flow field at the tail of the bidirectional pump gap. [ABSTRACT FROM AUTHOR]

The pattern of vegetation along the cross-section of macrophyte-dominated shallow waters is generally uneven, which affects water velocity and turbulence. This study examined the velocity and turbulence in the open channel with an uneven transverse distribution of vegetation in laboratory flume experiments. Two vegetation patterns were tested: emergent vegetation which covered part of the channel, and a symmetrical combination of submerged and emergent vegetation canopies along the lateral direction of the flume. The flow was measured using a three-dimensional Acoustic Doppler Velocimeter. The velocity and turbulence characteristics were analyzed under three vegetation densities and five discharge scenarios. Results showed that the longitudinal mean velocity changed with vegetation density and flow discharge when vegetation was unevenly distributed in a lateral direction. The strong variation in shear stress at the emergent vegetation–open water intersections and submerged–emergent vegetation intersections resulted in large-scale vortices at the interfaces. The formation processes of stem-scale turbulence and shear-scale turbulence under different vegetation scenarios were discussed. A turbulent kinetic energy model within partly obstructed vegetation canopies was established, which helped to identify the development of horizontal and vertical coherent vertices. • Flow and turbulence in unevenly distributed vegetated flows were analyzed. • The longitudinal velocity varied with vegetation density and input discharges. • Strong variations of shear stress at the interface resulted in large-scale vortices. • A turbulence model within a partly emergent vegetation canopy was established. [ABSTRACT FROM AUTHOR]

Using particle agglomeration to help separate fine particles receives increasing attention in air purification processes. Recent studies suggested that enhanced turbulence using bluff bodies can significantly improve the agglomeration of fine particles. However, since micron-sized particles are difficult to measure, the current exploration of flow fields and particles is mainly based on simulations and lacks experimental validation. This paper innovatively used a phase doppler particle analyzer to measure the flow field in terms of velocity, streamline and turbulence intensity, as well as particle size and number concentration in an agglomeration chamber with a bluff body located at the center. Different shaped bluff bodies were also considered. It was found that low-velocity recirculation region with different shapes appeared in the wake, and vortex flow with special structures were observed. From the perspective of particles, the development of the flow field generated by a single bluff body effectively caused an increase in particle size and a decrease in particle number, which is because that the flow field promotes collisional agglomeration. More specifically, for V-structure bluff body, the particle size improved from 6 μm to a maximum of 13 μm and the particle number concentration decreased by 8 times. The agglomeration efficiency for PM 2.5 and PM 10 reached 89.06% and 87.38% respectively. Furthermore, by analyzing the velocity of different sized particles, it was reasonable to assume that different sized particles appeared to have velocity differences due to recirculating vortex flow, while the overlapping trajectories of positive and negative moving particles was mainly responsible for the collision probability enhancement. This paper presents new insights into particle agglomeration separation for this environment-friendly and low-cost technology. [Display omitted] • Flow field and particles were observed simultaneously by PDPA experiments. • The addition of the bluff body considerably enhances the particle size. • V-structure has the most considerable effect in enhancing the particle size. • Different sized particles show significant velocity differences in the wake. • Particle-Particle collision probability is improved by recirculating vortices. [ABSTRACT FROM AUTHOR]

• A novel ANN-CFD based modelling methodology reported for simulating flow in a batch vortex mixer. • Two-phase flow problem requiring interface tracking simulations reduced to a single-phase flow problem. • ANN model trained with a large number of experimental data is used to predict vortex shape. • Validation of ANN-CFD model with the PIV data reported in literature. • Velocity profiles obtained from ANN-CFD model show good match with the profiles obtained from VOF simulations. • Validated ANN-CFD model used to have detailed insights into the flow and turbulence structures. The study presents a novel ANN-CFD model for simulating flow in a vortex mixer (an unbaffled vessel stirred by a magnetic stirrer). Large eddy simulations (LES) are performed to simulate flow and turbulence considering presence of both air and liquid phases. The flow fields in air and liquid phases are coupled by applying suitable boundary conditions at the air–liquid interface represented by the vortex. The shape of the vortex is built-in in the computational domain and obtained by using an artificial neural network (ANN) model trained and validated with the data obtained from experiments carried out to capture the vortex shape under different parametric conditions. ANN-CFD model is validated with PIV data reported in literature. The ANN-CFD model reduces the computational time significantly by obviating the need of performing computationally very intensive interface tracking simulations. The model is used to understand hydrodynamics and turbulence characteristics of flow in the vortex mixer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interaction of a bubble-particle aggregate with a confined vortex investigated. • An interface resolved 3D CFD model developed to quantify the interaction dynamics. • Highspeed shadowgraphy and PIV experiments performed to validate the CFD model. • Correlation of vorticity and local energy dissipation rate (ε) determined from CFD model. • A force-balance model used to predict particle detachment using ε. In flotation, interactions of bubble-particle aggregates with turbulent flow structures in the liquid medium result in particle detachment. This study aims to simulate this phenomenon involving a bubble-particle aggregate (bubble diameter ∼ 3 mm and particle diameter ∼ 314 µm) interacting with a turbulent flow structure manifested as a confined vortex in a square cavity connected to a square cross-section channel. An interface resolved three dimensional (3D) computational fluid dynamics (CFD) model was developed to quantify the bubble-vortex interaction dynamics over a range of channel Reynolds numbers. The CFD model produced a good agreement with the experimentally measured vorticity magnitude, local energy dissipation rate, and bubble motion. It was shown that a bubble-particle aggregate could be captured within the vortex by suitably varying the channel Reynolds number, eventually leading to particle detachment. A separate force balance analysis was performed to determine a criterion for particle detachment utilising the CFD model predicted vorticity and local energy dissipation rate. It was shown that a critical local energy dissipation rate ∼ 1.59 m2/s3 was required for particle detachment to occur, which was also verified experimentally. [ABSTRACT FROM AUTHOR]

The internal turbulence formed within artificial reefs (ARs) is extremely important. Laboratory experiments were conducted using Particle Image Velocimetry (PIV) to observe the influence of reef configuration on the current and turbulence features of perforated box-type ARs via arranging from one to three blocks, corresponding to the aspect ratio of 1.05, 2.09 and 3.14 respectively. A numerical model with same specifications of the PIV experiment was built and the calculated results were verified using experimental data. Several vortices with different scales and strong turbulence intensity are formed inside and behind the reef. The internal turbulence has been fully developed under the reef configuration with aspect ratio of 2.09. The internal turbulent flow structure was dominated by the horizontal vortex structure, which displayed certain symmetry in the transverse direction because of symmetrical reef structure. The vorticity pattern inside the reefs was dipole-type, regardless of aspect ratio, consisting of two pairs of high-vorticity but opposite rotation direction clouds formed behind the openings of reef stoss face, and symmetrical distribution in both vertical and horizontal direction. This study aims to reveal the reef-induced internal flow structure and fills the gap of existing research. • 3D vortex structure within reef was observed in various reef aspect ratios using PIV. • Horizontal vortices dominate the inner turbulence and increase with reef lengthening. • Dipole-type vorticity pattern appears behind the openings of stoss face inside reefs. • A strong turbulence U-shaped region was formed around reefs due to vx fluctuation. • The reef openings play a key role to internal flow structure and water exchange. [ABSTRACT FROM AUTHOR]

• The capabilities of different drag models under high turbulence /vortex flow conditions are shown. • Impacts of turbulence effects on drag modelling are presented. • A hybrid drag model is proposed for high turbulence flow conditions. • Two-phase flow hydrodynamics under complex flow conditions is analyzed. • Gas velocity and void fraction predictions are compared with experimental data. The accuracy of the modelling of gas–liquid flows depends strongly on a suitable modelling of the interfacial forces. Among these, drag is dominant. Most drag models reported in the literature have been derived and validated only for laminar or low-turbulent flow conditions. In this study, we numerically evaluated several drag models from the literature for high-turbulent gas–liquid flow around an obstacle in a pipe that creates a distinct vortex region. We performed Computational Fluid Dynamics (CFD) simulations and compared the void fraction and gas velocity profiles with experimental data obtained by ultrafast X-ray computed tomography. We found that all models, except Schiller&Naumann and Feng, predicted the void fraction well compared to experimental data upstream of the obstacle, i.e., for a developed two-phase pipe flow with axial symmetry. However, the void fraction downstream is greatly overestimated by all models except those that appropriately consider the turbulence effects. Based on the results, a hybrid drag model is proposed that significantly improves the prediction of the void fraction. [ABSTRACT FROM AUTHOR]