Cross-sectional Width Research Articles

Comparison of Hot Cracking Susceptibility of TIG and Laser Beam Welded Alloy 718 by Varestraint Testing

Reduced hot cracking susceptibility is essential to ensure the flawless manufacturing of nickel superalloys typically employed in welded aircraft engine structures. The hot cracking of precipitation strengthened alloy 718 mainly depends on chemical composition and microstructure resulting from the thermal story. Alloy 718 is usually welded in a solution annealed state. However, even with this thermal treatment, cracks can be induced during standard industrial manufacturing conditions, leading to costly and time-consuming reworking. In this work, the cracking susceptibility of wrought and investment casting alloy 718 is studied by the Varestraint test. The test is performed while applying different welding conditions, i.e., continuous tungsten inert gas (TIG), low frequency pulsed TIG, continuous laser beam welding (LBW) and pulsed LBW. Welding parameters are selected for each welding technology in order to meet the welding quality criteria requested for targeted aeronautical applications, that is, full penetration, minimum cross-sectional welding width and reduced overhang and underfill. Results show that the hot cracking susceptibility of LBW samples determined by the Varestraint test is enhanced due to extended center line hot cracking, resulting in a fish-bone like cracking pattern. On the contrary, the minor effect of material source (wrought or casting), grain size and pulsation is observed. In fact, casting samples with a 30 times coarser grain size have shown better performance than wrought material.

Analytical description of nanowires. I. Regular cross sections for zincblende and diamond structures.

Semiconductor nanowires (NWires) experience stress and charge transfer from their environment and impurity atoms. In response, the environment of a NWire experiences a NWire stress response which may lead to propagated strain and a change in the shape and size of the NWire cross section. Here, geometric number series are deduced for zincblende- (zb-) and diamond-structured NWires of diameter dWire to obtain the numbers of NWire atoms NWire(dWire[i]), bonds between NWire atoms Nbnd(dWire[i]) and interface bonds NIF(dWire[i]) for six high-symmetry zb NWires with the low-index faceting that occurs frequently in both bottom-up and top-down approaches of NWire processing. Along with these primary parameters, the specific lengths of interface facets, the cross-sectional widths and heights and the cross-sectional areas are presented. The fundamental insights into NWire structures revealed here offer a universal gauge and thus could enable major advancements in data interpretation and understanding of all zb- and diamond-structure-based NWires. This statement is underpinned with results from the literature on cross-section images from III-V core-shell NWire growth and on Si NWires undergoing self-limiting oxidation and etching. The massive breakdown of impurity doping due to self-purification is shown to occur for both Si NWires and Si nanocrystals (NCs) for a ratio of Nbnd/NWire = Nbnd/NNC = 1.94 ± 0.01 using published experimental data.

Comparison between the field performance of a Movable boards Ditch opener and conventional ditch opener in cultivated and uncultivated soils Part4: The Energy Utilization Efficiency

Energy utilization efficiency (EUE) for Movable boards ditch opener (MB) and for conventional ditch opener (CD) were compared using three operating depths for MB(30, 40 and 50cm), three angles between its movable boards, three foot wings widths and two soil types (cultivated an uncultivated soils). For CD there was one angle between its boards (65°), they were permanently fastened, one share width (35cm), one operating depth in the uncultivated soil only (25cm), could not penetrate such soil, and three operating depths in the cultivated soil.The results showed that EUE for MB increased as the operating depth increased in the cultivated and uncultivated soil whereas, for CD it increased in the cultivated soil only whereas, it could not penetrate the uncultivated soil more than 25 cm. However, the rate of increase was almost the same for both implements in the cultivated soil, EUE for CD increased from 5.57 to 7.93m3MJ−1 (2.36m3MJ−1) whereas, for MB, it increased from 9.64 to 11.78m3MJ−1 (2.14m3MJ−1). EUE for MB also increased with angle between its boards and the width of the wings of its foot while for CD did not occurred because it boards were permanently fastened to the machine frame at angle of 65° and it was provided with share rather than wings. EUE for MB was higher in the cultivated soil comparing with uncultivated soil.EUE for MB was higher than that for CD for all operating depths, angle between the boards and the width of the wings of the foot and in both soil types. The results showed that MB surpassed CD in field performance in addition to that it can penetrate the soil to the required depth whether it was cultivated or uncultivated soil. It also can produced different cross-section width ditches whereas, CD can produce one cross-section width ditches.

Optimization of reinforced concrete beams using Solver tool

Abstract Due to the development in structural analysis studies, optimization techniques have become part in the design of reinforced concrete structures. Making it possible to design structures with optimized cross-sections. Thus, the present study aims to implement optimization techniques, using the Solver tool, to design procedure of reinforced concrete beams following the precepts of Brazilian Standard ABNT NBR 6118:2014. Focusing to minimize the cost of reinforced concrete beams, where the design variables are the height and width of the beam cross-section and the constraints are imposed by the relevant technical standards and design variables limitations.

High-resolution Observations of Dynamics of Superpenumbral Hα Fibrils

Abstract We present high-resolution Hα observations of a small solar pore in NOAA active region 12661, using the 1.6 m Goode Solar Telescope equipped with high-order adaptive optics at Big Bear Solar Observatory. The observations reveal copious fine-scale chromospheric superpenumbral fibrils (with an average cross-sectional width of ∼0.″17 ± 0.″03), along with associated transit and intermittent flows with apparent speeds of 5–14 km s−1. Wavelet analysis and the spatio-temporal pattern of superpenumbral fibrils suggest that the observed flows along fibrils are not likely an oscillation/wave phenomenon. Based on our pseudo-Dopplergrams, we suggest that the observed flows may be a phenomenon similar to inverse Evershed flows in the chromosphere. The three-dimensional potential field model indicates that the pore and the surrounding fibrils are enclosed by fan-field lines forming a separatrix dome configuration. Such a magnetically confined configuration may help to maintain the steadfastness of the superpenumbral fibril dynamics.

Application of BRAHMA hydrodynamic model for flood forecasting

Flood forecasting models are of paramount importance to predict the flood and thereby warning the community living near the floodplains or the vulnerable areas. In the quest for understanding the complex processes of a river, scientist and researchers have given importance to river modeling both analytically and physically by conducting experiments in the laboratory. The numerical model which is basically a mathematical model has gained popularity in the last few decades. BRAHMA (Braided River Aid: Hydro-Morphological Analyzer) is a hydrodynamic model for simulating the spatial variation in water depth, flows, and velocities in the unsteady free surface flow. It is developed by IIT Guwahati in collaboration with Brahmaputra Board, Govt. of India. The BRAHMA 1-D model is capable of simulating both prismatic as well as non-prismatic channel reach. It is also capable of simulating channels with varying width and varying slope. In this paper, an attempt has been made to use the BRAHMA 1-D model for determining the water surface elevation at certain flood-prone areas of Ranganadi River which covers Assam and parts of Arunachal Pradesh, North-East India. The Ranganadi hydroelectric dam is situated in Arunachal Pradesh, India. In this study, the length of the river reach considered is 77.09 km from the Ranganadi Hydroelectric power project. The cross-sectional width of the river in different sections is extracted from Google Earth and depth was obtained by approximate field measurement. The peak release from the dam, the downstream water level and initial water levels are given as input to the model. The water levels at the particular sections of interest are computed as output from the model. From the generated output data set, it is possible to assess the vulnerable areas by the water levels which will be generated from the model.

Coefficient of Moment of Inertia for Ribbed RC Slab Beams

During the design process of monolithic ribbed slabs, engineers face a common issue how to correctly evaluate stiffness of the beams. When Bar and Plate elements are used for analysis of the slabs, the neutral axis of those members are in the same level, therefore the stiffness of (T) shape cross-section is not considered correctly in the calculations. In this case the internal forces are obtained incorrectly as well as deflections of the beams are overestimated. A simple method is discussed in this paper, which allows engineers to calculate internal forces and deformations of mentioned type slabs more accurately with FEM programs by using Bar and Plate elements. The method is based on Bar elements moment of inertia adjustment. After the comparative analysis of differences between moment of inertia of (T) and (+) shape cross-sections as well as deflection discrepancies, the adjustment coefficient expression is presented. In order to reflect the actual behaviour of ribbed slabs even more accurately the influence of shear deformations is also considered. In this case not only the member geometry but the material properties, loading scheme and even supports are taken into account in the calculations of the adjustment coefficient. Selection of the most appropriate (effective) flange width of (T) shape cross-section is also analysed in this paper. Comparative calculations were done using different effective flange widths beff calculated by EC2 (Eurocode 2), “STR” (Lithuanian Construction Technical Regulations) and ACI (American Concrete Institute) methods. In order to assess the reliability of the proposed calculation method and the calculation results all plates were also analysed using Solid elements. Application of the presented expressions of moment of inertia coefficient will allow engineers to evaluate stiffness of (Γ) and (T) shape cross section beams simply, fast and accurately enough for most of structural engineering calculations.

LOAD-CARRYING CAPACITY INCREASE OF ARCH-TYPE TIMBER ROOF

Possibility to increase load-carrying capacity of arch-type timber roof of multifunctional public building with the span equal to 60 m was analysed. Three-hinged segment arches with the rectangular glued cross-sections are considered as the main load-carrying structures in the transversal direction. Freely supported purlins with the massive rectangular cross-sections are considered as the main load-carrying structures in the longitudinal direction. The dependences between height of the arches, it bays and distances between the bracing members strengthening top and bottom zone of the arches cross-sections so as relative materials consumption and specific load-carrying capacity of the arches were obtained as the second power polynomial equations. Height of the arches and it bay changes within the limits from 10 to 30 and from 2 to 9 m, correspondingly. The distances between the bracing members strengthening top and bottom zone of the arches changes within the limits from 2 till 10 and from 4 till 16 m, correspondingly. The arch-type timber roof was considered under the action of the load combination which include structural dead weight, drifted and undrifted snow loads and wind loads. The relative materials consumption of the arches was determined as a relation between the dead weight of the arch to it span and changes within the limits from 24 till 114 kg/m. Glued and solid timber with strength classes GL24h and C24 are considered as materials of arches and purlins, correspondingly. The specific load-carrying capacity of the arches was determined as a relation between load –carrying capacity of the arche and volume of structural materials. Specific load-carrying capacity of the arches changes within the limits from 0.23 till 0.83 kN/m/t in the case, if purlins are taken into account. It was shown, that the rational from the point of view of materials consumption and specific load-carrying capacity height of the arche, it bays so as the distances between the bracing members strengthening top and bottom zone of the arches are equal to 15, 7.5, 5 and 15 m, correspondingly. Corresponding values of relative materials consumption and specific load-carrying capacity are equal to 24 and 0.23 kN/m/t. The depth and width of the arche cross-section were equal to 1617 and 318 mm, correspondingly. It was shown, that strengthening of the arches cross-section by the steel bars of strength class B500 and carbon fibre reinforced plastic tape Sika Crbo Dur S512 enables to increase load-carrying capacity of the arche by 10.20 and 9.48%, correspondingly. But common use of the steel bars together with the carbon fibre reinforced plastic tapes enables to increase load-carrying capacity of the arche by 18.89%.

Analysis of Thermal Stress and Strain in BGA Solder Joint Based on Microchannel Ceramic Substrate

A finite-element analysis model of ball grid array (BGA) solder joints for microfluidic ceramic substrates was established, and fluid-structure-coupled finite-element simulation analysis was performed. The influences of three microchannel structures of straight-line type, rectilinear type, and polyline type, and different microchannel structure parameters on the stress and strain of BGA solder joints were analyzed. Sixteen orthogonal microchannel structure parameter levels were designed using an orthogonal. Combining and establishing corresponding 16 groups of finite-element models for simulation analysis, the maximum stress data of the 16 BGA solder joints obtained were analyzed by range analysis and variance analysis. The results show that the microchannel spacing has the greatest impact on BGA solder joint stress. Followed by the length of the microchannel cross section, and again the width of the microchannel cross section, analysis of variance showed that in the case of a confidence of 95%, the microfluid spacing of BGA solder joints has a significant effect on the stress of BGA solder joints and straight-arranged microflow. The length and width of the cross section had no significant effect on the weld stress. The microchannel experimental samples corresponding to the simulation analysis were produced, and the accuracy of the simulation results was verified by experiments within a certain error range and the thermal fatigue life analysis of BGA solder joints on ceramic substrates.

Laser welding of AlSi12 and S355 with a 10 kW single mode fiber laser

In this study, fast welding of an aluminum alloy AlSi12 and a structural steel S355 was investigated using a single mode fiber laser system delivering a maximum laser power of 10 kW with a laser beam quality of M2 = 2. The laser beam was focused with a welding head OL YW50 F500 HQ from Precitec GmbH & Co. KG resulting in a spot size of 70 μm, thus delivering a maximum intensity up to several 108 W/cm2 to the workpiece surface. Therefore, narrow weld seams and large penetration depths could be achieved. However, detrimental effects like humping, spiking, spatter tendency, pore formation, and hot cracking, reported by Li et al. [J. Mater. Process. Technol. 214, 565–570 (2014)] and Zhang et al. [Optic Laser Technol. 98, 97–105 (2018)], have been observed at some parameter settings. The welding experiments performed on AlSi12 with a laser beam power of 10 kW, focus position on the material surface, and welding speeds from 2 to 10 m/min reveal penetration depths of about 12 mm independently from the distinct welding speed. Therefore, the weld bead width was 5.5 mm for 2 m/min, thus decreasing to 1.1 mm at the highest welding speed of 10 m/min. By shifting the focus position inside the material, the penetration depth rises significantly and reached a maximum of 17.5 mm for a welding speed of 2.5 m/min and a focus position of 6 mm underneath the sample surface. For this, the weld cross section width, measured at half of the penetration depth, was 2.2 mm. For the structural steel S355, the maximum penetration depth was determined to be 19.5 mm, here with 10 kW laser power, focus position on the material surface, and a comparable welding speed of 2.4 m/min. Therefore, a weld bead width of about 0.75 mm was measured, while the weld cross section width was about 0.55 mm. Finally, first butt welds of 19.5 mm thick S355 samples were generated characterized by smooth welds with a bead width of about 2.5 mm and a weld cross section width of 0.5 mm, respectively.

An experimental investigation of changing cut mark cross-sectional size during butchery: Implications for interpreting tool-assisted carcass processing from cut mark samples

Butchery occurs at the intersection between technology, carcass processing behavior, and animal anatomy, and records traces on fragmentary specimens including cut marks. The causal factors and contexts that generate bone surface modifications have been well-studied in experimental archaeology but the ways in which cut mark size or morphology change with time during butchery in response to tool edge dulling or carcass desiccation is currently unknown. This study examines cut mark cross-sectional width and depth change during a sequence of experimental butchery trials that control for the effects of animal size, bone portion density, tool weight, and flake versus core tool type. Mark size is measured from vinyl molds under low-power magnification (40×) and compared to more precise 3d measurement techniques. Tool type and the order of carcass segment defleshing was systematically varied across the experiment, and a linear mixed effect regression model was used to explore the impact of these fixed factors and consider random variability introduced by potential differences in the four cows butchered by eight tools. Mark width and depth samples were negatively related to the density of the portion where marks occur, tool weight had a weak, but significant influence on mark size, and marks incised at different stages in the sequence of defleshing events were similar in width and depth. With current measurement techniques and the large variability in mark size produced during butchery, it is not impossible to infer the timing of mark creation during a tool's use life or its place in a sequence of butchery events, but methodological advancement may overturn this pessimistic conclusion.

Design of acoustic foam wedge panels by finite element frequency domain acoustical analysis

Acoustic foam wedge panels provide good sound absorption qualities in the mid and high frequency ranges. In this study, a finite element frequency domain acoustical analysis is used for analysis. Such a numerical method is more efficient than the earlier studies by saving the calculation time on the elements of the incident acoustic field. During the design of a wedge panel, the cross-sectional width and the area of one section of the wedge panel are kept the same throughout the study. By varying the wedge angle, the maximum sound absorption capability of the wedge foam can be found. It is concluded that in the interested frequency regions, 100–4000 and 2000–4000 Hz, the wedge foam with wedge angle of 31° has the excellent sound absorption capability.

On the impact of the aspect ratio on the formation of large-Scale structures in turbulent mixed convection in a cuboidal sample

Temperature measurements combined with Particle Image Velocimetry (PIV) were performed in a cuboidal convection sample with a square cross section (width / height). The objective of the study is to analyze the influence of the aspect ratio Γxz=L/H and the Archimedes number Ar on the large-scale coherent structures in mixed convection. Air at ambient pressure was used as working fluid (Pr=0.7). The aspect ratio was varied between 1 ≤ Γxz ≤ 4 (length / height) and the variation of the Archimedes number was achieved by prescribing the inflow velocity of an air jet, which was superimposed on the thermally induced flow via an inlet and outlet channel. The Rayleigh number was kept constant at Ra=2.0×108. A model, adopted from pure thermal convection, was used to extract the number of convection rolls from the circumferential temperature distribution measured along the sidewalls of the convection sample. For a fixed Archimedes number (Ar ≈ 4), the number of thermally induced large-scale circulations (LSCTC) increased with the aspect ratio of the sample. Specifically, starting with Γ=2, a linear dependence with unity slope was found. A decrease of the Archimedes number led to a transition from the single LSCTC structures to FC-dominated LSCs (LSCFC) for Γ=1 and Γ=2, whereas the multi-roll structures found for Γ=3 and Γ=4 were more stable even for higher inflow velocities.

Strain Effectiveness of Gate-all-around Silicon Transistors with Various Surface Orientations and Cross-sections

We investigate the effect of strain on the device characteristics of gate-all-around (GAA) NMOS with various configurations, including crystal orientation, cross-sectional shape, and strain conditions, via device simulation. After verifying the strain dependence of mobility of various surface orientations with the literature, we apply the strain transport model to GAA MOSFETs which have different sidewall orientations depending on the channel direction. Drive current enhancement is the largest for the (001)/110 case under large uniaxial tensile strain values exceeding 1%. In addition, we found that cross-sectional width of the nanosheet is a key parameter in maximizing the drive current for a given footprint. Optimization of device and strain configuration of single-stacked GAA devices is necessary to meet device performance specifications for sub-7nm technology.

Flexural strength and serviceability evaluation of concrete beams reinforced with deformed GFRP bars

This paper presents a study to investigate serviceability, strength, and deformability of normal- and high-strength concrete beams reinforced with deformed glass-fiber-reinforced-polymer (GFRP) bars under flexural loading. Understanding the flexural behavior of concrete beams reinforced with deformed GFRPbars with normal- and high-strength concrete would contribute to the existing literature and would provide information critical to the further use of deformed GFRP bars as internal reinforcement for concrete structures. Eight beams with a cross-sectional width and height of 200 mm and 300 mm, respectively, and a clear span of 2700 mm were tested under two-point flexural loading until failure. Four beams were made with 35 MPa normal-strength concrete (NSC); the other four with 65 MPa high-strength concrete (HSC). The bottom/tensile reinforcement of each beam consisted of two GFRP bars. Four different GFRP bar sizes (12 mm, 16 mm, 20 mm, and 25 mm in diameter) were used with reinforcement ratios ranging from 0.38% to 1.63%. Seven beams failed in concrete compression and the eighth beam failed in tension when the FRP ruptured. The test results showed that increasing the FRP reinforcement ratio had a greater effect on the service moment than the resistance moment. The effects of bar spacing on the behavior of wide beams were also investigated, revealing that the service moment increased when the bar spacing decreased, while the resistance moment increased when the concrete strength increased. In addition, the deformability concept produced significantly higher ductility indices than the energy-based concept. Neither method evidenced a clear trend in the ductility indices of the tested beams. A new approach was proposed to determine the ductility index of concrete beams with FRP bars based on beam curvature. This approach demonstrated a clear trend with the tested beams: the high-strength concrete beams had higher ductility indices than the normal-strength concrete beams.

Laser-based magnetic micro-inscription: Surface heating versus deep penetration regime

The technology of magnetic micro-inscription can be used for in-axis positioning measurements directly from a linear actuator which reduces the cost and size of the whole system. In this paper, two different regimes for laser-based magnetic micro-inscription were compared: a surface heating and a deep penetration heating. The first regime is the same as conductive heating and the second is similar to the process of keyhole welding. The experimental results show that both processes can be effectively stabilized by means of controlling the width and depth of the microstructure transformation cross-section, as they are able to compensate for external disturbances, such as higher roughness, and the gradual accumulation of heat. From numerical analysis it could be seen that the perfect inscription should have depth equal or more than 0.8 of period of inscription and width around 0.80 ± 0.05 of period which is not achievable with the surface heating regime, but only with the deep penetration regime. Results show that the deep penetration heating requires 5-times less laser energy which leads to lower heat accumulation and a more stable process, is unaffected by disturbances, such as higher roughness, and provides an almost 15% higher relative amplitude as measured by the reference magnetic sensor.

Minimizing cross sectional pulse width difference between central and edge parts of SBS compressed beam.

For minimizing the spatial cross-sectional pulse width difference in the reflected SBS compressed beam, two new methods, blocking beam edge and parameter optimization, are proposed and compared experimentally. Results show that the sub-nanosecond compressed pulse width at the beam edge can be obtained by using both two methods in this paper. The pulse width difference between the beam center and the edge is minimized through selecting a proper medium and the optimized structural parameters in a single-cell SBS compressor. Its energy efficiency reaches up to 81.5% by using the medium HT110 and is two times higher than that of the blocking beam edge method. The compressed pulse width's stability improved greatly by using these two methods.

A semi-analytical formulation for estimating the fundamental vibration frequency of historical masonry towers

A semi-analytical formulation is proposed for estimating the fundamental vibration frequency of historical masonry towers. In this method, in addition to general tower geometrical properties such as its effective height, cross-sectional width, and wall thickness, the influence of openings in perimeter walls including opening size and configuration are explicitly considered. For this purpose, a comprehensive numerical study is carried out using the ABAQUS software to evaluate the effects of various geometrical and material parameters on the fundamental frequency of towers. Then, a semi-analytical formulation is developed through statistical analysis of the generated database. To evaluate the accuracy of the proposed formulation, a number of towers, for which dynamic test results or numerical results are available, are selected and their fundamental frequencies are determined employing the proposed method. The comparison of the frequencies obtained using the semi-analytical formulation with those reported in the literature shows that the proposed formulation evaluates the fundamental frequency of masonry towers with an acceptable accuracy.

Relative information from thermal infrared imagery via unoccupied aerial vehicle informs simulations and spatially-distributed assessments of stream temperature

Stream temperature is a measure of water quality that reflects the balance of atmospheric heat exchange at the air-water interface and gains or losses of water along a stream reach. In urban areas, stormwater sewers deliver water with varying magnitude and temperature to streams at variable timescales. Understanding the impacts of stormwater through space and time is therefore difficult to do with conventional approaches like in situ sensors. To study the impacts of stormwater on creek water temperatures, we combined in situ water temperature observations with thermal infrared (TIR) imagery collected via unoccupied aerial vehicle (UAV). Imagery was collected in May, June, and July of 2017. As ongoing work with UAV-based TIR suggests that this imagery is prone to poor accuracy, we focused on creating several data products beyond absolute water temperatures that can be used to assess temporal and spatial water temperature variations. In particular, TIR data products were used to extract the length of the observed stormwater plume as well as the width of the creek cross-section impacted by stormwater. From these values, we conclude that relatively narrow stormwater plumes affecting a small fraction of creek width can alter creek water temperatures for considerable distances downstream. We also applied TIR data to constrain results of a deterministic stream temperature model (HFLUX 3.0) that simulates the physical processes affecting stream heat exchanges. Stormwater plume lengths obtained from TIR imagery were used to refine spatially-distributed simulations, demonstrating that relative temperature information obtained from UAV imagery can provide useful calibration targets for stream temperature models. Overall, our work demonstrates the added value of UAV datasets for understanding urban stream temperatures, calibrating water quality models, and for modeling and monitoring of the impact of spatially explicit hydrologic processes on stream temperature.

Prospective registry validating the reproducibility of mitral paravalvular leak measurements in a standardized real-time three-dimensional transesophageal echocardiography algorithm for optimal choice of the closure device

IntroductionTranscatheter paravalvular leak closure (TPVLC) has become a well-established method of treatment for patients with paravalvular leak (PVL) causing heart failure or significant hemolysis. Nonetheless, the method of optimal PVL sizing and subsequent device choice requires standardization. For this purpose a real-time three-dimensional transesophageal echocardiography (RT-3D TEE) algorithm was developed in our institution. It has proven clinically useful with results successfully translated into type, size, and number of occluding devices. Still, the reproducibility of measurements has not been previously verified.AimTo investigate the intra- and inter-observer variability of measurements in a RT-3D TEE algorithm developed for optimal choice of occluding devices during TPVLC.Material and methodsThree echocardiographers, with RT-3D TEE clinical experience ranging from 1 to 8 years, analyzed recordings of 20 mitral PVLs according to our standardized protocol. PVL channel cross-sectional area (CSA), width (W) and length (L) were measured at the level of the vena contracta. Each echocardiographer performed the measurements twice on different days, individually and blinded to other participants’ results.ResultsMeasurements of PVL CSA, W and L showed intra- and interobserver agreement of 0.98, 0.93, 0.92 and 0.95, 0.88, 0.87, respectively.ConclusionsThe presented algorithm enables standardized utilization of RT-3D TEE for appropriate TPVLC device choice with low intra- and inter-observer variability.