Small Pitch Research Articles

Effect of Variation of the Aspect Ratio of Rectangular Twisted Tapes Inserted in a Circular Pipe on the Thermal Performance

Abstract This study aims to determine the effect of the aspect ratio of the cross section of a rectangular twisted tape on the laminar heat transfer characteristics inside an isothermally heated circular pipe. Detailed three-dimensional simulations reveal facts that would be difficult to estimate otherwise. A novel study of the evolution of the axial and secondary velocity fields as well as the temperature field within the pipe is presented to understand the flow physics behind the heat transfer enhancement. The three-dimensional simulation results are used to accurately calculate the portion of the total energy of the flow that is converted to secondary kinetic energy. In addition to the Nusselt number and friction factor, three parameters, viz. relative increase in heat transfer coefficient, relative increase in pressure drop, and thermo-hydraulic performance factor are used to quantify the effect of the twisted tape. While both the heat transfer and the pressure drop increase with a decrease in the twist ratio (TR), the thermo-hydraulic performance factor (THPF) is found to become almost independent of TR as the aspect ratio (AR) decreases to low values. It is inferred from the present results that although a twisted tape with a small pitch and large aspect ratio enhances heat transfer performance, a lower aspect ratio may provide a better option from a power requirement perspective. Hence, this work shows, for the first time, that a square-like cross section of the twisted tape could be advantageous.

Amp-Holo-Net enables speckle-free and high-quality coaxial amplitude-only holographic display

At present, amplitude-only holograms (AOH) are widely applied because of the high response speed and small pitch of amplitude spatial light modulators. However, AOHs are generally generated by traditional diffraction theories, and there are no effective deep learning algorithms to generate high-quality coaxial AOHs, which makes it difficult to achieve speckle-free, high-quality holographic displays using amplitude spatial light modulators. Thereby, we propose two cascaded deep neural networks, embedding physical models of the coaxial AOH to generate speckle-free and high-quality coaxial AOHs within an acceptable time, named Amp-Holo-Net, which is the first work that introduces deep learning to generate coaxial AOHs. We demonstrate the superiority of the proposed method through simulation, achieving an 81% reduction in speckle contrast of two-dimensional (2D) monochrome reconstruction and a 60% improvement in peak signal-to-noise ratio of 2D color reconstruction compared with point source method, and optical experiments are conducted to verify the validity of the proposed method. We believe our method fills the blank of AOH algorithms and paves the way for holographic displays based on amplitude spatial light modulators.

Membrane piezoelectric MDS-actuator with a flat double spiral of interacting electrodes

A schematic diagram and mathematical model of functioning of a new piezoelectric membrane (MDS) actuator with double spiral (DS) electrodes on the upper and/or lower surfaces of a thin piezoelectric layer with axisymmetric and periodic (with a small period) in radial coordinate mutual reversed electric polarization are presented. The polarization of the layer was realized as a result of connecting the polarizing electric voltage of the appropriate value to the outputs of the double spirals of the electrodes. The electrodes of each (upper and lower) double spiral of the MDS-actuator are made in the form of electrodeposited ribbon coatings on the surfaces of the piezoelectric layer in close proximity to each other (due to the small spiral pitch) to create high values of electric field strength along the lines of force in localized areas of the piezoelectric layer between them when an alternating or constant control electric voltage is connected to the electrodes, in particular, with positive and negative values of the electrical potentials. Importantly, the electric field force lines and, as a consequence, the polarization of the piezoelectric layer of the MDS actuator are oriented mainly along (i.e. towards or against) the radial coordinate of the membrane, in contrast to many conventional actuator schemes. The results of numerical modeling for a circular elastic membrane with piezoelectric actuators installed on its upper and lower surfaces confirmed the effectiveness of the proposed piezoelectric MDS-actuator when it functions according to the “bimorph” scheme, including the use of the proposed new structural element (section) – a piezoelectric “compression ring” MDS at various geometric and control parameters. The effect of a significant increase in the membrane deflection with installed piezoelectric MDS-actuators compared to the use of traditional homogeneous plate piezoelectric actuators of bimorph type for different conditions of the membrane fixation, in particular, stationary (rigid) fixation of its center is revealed. For a hybrid piezoelectric MDS-actuator including independent concentric round and circular (i.e. “compression ring”) sections, the non-monotonic nature and numerical analysis of the nonlinear dependence of the largest deflection at the center of a hinge-immobile membrane fixed at the edge on the ratio of the radii of its round and circular MDS sections were revealed. The cases in which the effect of the “compression ring” is manifested, i.e. when the maximum deflection of a membrane with the “compression ring” exceeds the best possible value of the deflection of this membrane without its use in the traditional “bimorph” scheme, are identified. The new piezoelectric MDS-actuator can be used in micromechanics, controlled optics, sensor technology, acoustics, in particular, in the manufacture of piezoelectric acoustic or sensor elements of membrane type, electromechanical transducers for vibration energy collection.

Flow topology and turbulent characteristics of cross flow over a wall bounded inline tube bundle with small pitch to diameter ratio

The characteristics of cross flow over tube bundles with small pitch to diameter ratios (S/D) are preferable for intermediate heat exchangers (IHXs) of High Temperature Gas-cooled Reactors (HTGRs) due to they can further improve the compactness of such heat exchangers. However, small S/D usually introduces more complex flow phenomena, such as biased wakes, main frequency disappearing in velocity spectrum, as well as the quasi-stable phenomenon. In the current investigation, the cross flow over an inline tube bundle (8 columns and 20 rows) with S/D = 1.25 was experimentally investigated in a low-speed wind tunnel using various measurement techniques including two-dimensional, two-component (2D2C) Particle Image Velocimetry (PIV), split hot film anemometry, surface pressure measurements and wind tunnel balances. Firstly, PIV was used to obtain the time averaged streamwise and transverse velocity fields (in z-normal plane). The direction of the turbulent wakes and transverse flows behind the tubes were investigated. It was found that at the middle spanwise plane (z = 0 mm), the wakes and transverse flows are both towards the nearby bounding wall. However, at planes closer to the end of the tubes, the directions of the wakes and transverse flows are away from the bounding walls (z=±200 mm). To further confirm this phenomenon, split hot films are used to measure the transverse flow direction at different streamwise and spanwise positions, revealing that the direction of the wakes and transverse flows remained consistent at different streamwise positions. Streamwise and spanwise velocity fields (in y-normal planes) measured using PIV demonstrates that there exists spanwise flow (z direction) in different transverse planes (y-normal planes) within the tube bundle. The spanwise and transverse flows form secondary flows in the plane normal to the flow direction (x-normal plane). The secondary flows are symmetrical about the z = 0 mm plane and y = 0 plane. Therefore, the streamlines within the tube bundle are in a helical shape. In the current surface pressure measurement, two sets of main frequencies corresponding to Sr = 0.047 and 0.112 were identified in the surface pressure spectrum. Moreover, transverse velocity sudden jumps were observed in specific regions from the reconstructed PIV results using Proper Orthogonal Decomposition (POD). This phenomenon was particularly prominent at the plane (z = 150 mm) where the wake and transverse flow directions transition.

Laboratory and beam-test performance study of a 55 µm pitch iLGAD sensor bonded to a Timepix3 readout chip

This contribution reports on characterisation results of a large-area (2 cm2) small pitch (55 µm) inverse Low-Gain Avalanche Detector (iLGAD), bonded to a Timepix3 readout chip. The ilGAD sensors were produced by Micron Semiconductor Ltd with the goal to obtain good gain uniformity and maximise the fill-factor — an issue present with standard small-pitch LGAD designs. We have conducted detailed performance evaluations using both X-ray calibrations and beam tests. An X-ray fluorescence setup has been used to obtain energy calibration and to identify the optimal operating settings of the new devices, whereas the extensive beam tests allowed for a detailed evaluation of the detector performance. The beam-tests were performed at the CERN SPS North Area H6 beamline, using a 120 GeV/c pion beam. The reference tracking and time-stamping is achieved by a Timepix3-based beam telescope setup.The results show a gain of around 5 with very good uniformity, measured across the whole gain area, as well as a hit time resolution down to 1.3 ns without correcting for the time-walk effects. Furthermore, it is shown that the gain opens the possibility of a good X-ray energy resolution down to 4.5 keV.

First experimental confirmation of island SOL geometry effects in a high radiation regime on W7-X

Abstract This work characterizes the detachment behavior and radiation characteristics of the low
iota configuration in the Wendelstein 7-X (W7-X) stellarator. The island scrape-off layer (SOL) of the
low iota has a poloidal mode number of 6 islands surrounding the last closed flux surface (LCFS).
The island geometry of the low iota configuration is significantly different to that of the standard
magnetic field configuration, whose detachment characteristics have already been described in previous
work[2, 3, 4]. Experimental results show that the radiation pattern in the low iota configuration
is starkly different to that of the standard magnetic field configuration, with radiation concentrated
at the island SOL O-points, rather than the X-points. Additionally, this O-point localized radiation
pattern is associated with unstable detachment, with both radiation oscillations in experiments and the
lack of a self-consistent plasma solution at high radiated power fraction in EMC3-Eirene simulations.
EMC3-Eirene simulations are used to understand the radiation distribution. It was found that the O-
point localized radiation arises first from local impurity accumulation near the parallel flow stagnation,
which is located close to the geometrical center of the island (”O-point”). The local cooling in this
region leads to plasma condensation in the islands in closest magnetic connection to the divertor target
plates. The heat source to this region of the island, which is thermally isolated from the upstream heat
source in terms of parallel transport, must arise via perpendicular heat transport. This heat source is
expected to be large for the low iota configuration due to its very small internal island field line pitch.
This work highlights the importance (complementary to previous work, e. g. [5, 6]) of the internal
island field line pitch not only on the radiation pattern, but also the detachment performance of the
island divertor.

Improving magnetic properties of FeCrCo films by facilitating the internal α-γ phase transition through Pt diffusion

FeCrCo magnetic films are suitable candidates for use as magnetic code disk materials in high-accuracy magnetic encoders. The performance and material uniformity of FeCrCo films are crucial for high-accuracy servo control of the encoder. However, enhancing coercivity and maintaining material uniformity while ensuring sufficient remanence in FeCrCo films pose challenges. Herein, Pt (t nm)/FeCrCo (100 nm) films were prepared via magnetron sputtering and subsequent vacuum annealing. The remanence of the FeCrCo (100 nm) monolayer film is 520 emu/cm3, with a coercivity of only 380 Oe. However, after using Pt as the buffer layer, the remanence of Pt (1 nm)/FeCrCo (100 nm) and Pt (2 nm)/FeCrCo (100 nm) films is 320 emu/cm3 and 250 emu/cm3 respectively, while the coercivity increases to 520 Oe and 625 Oe respectively, representing improvements of 37 % and 65 %. This significant increase in coercivity is achieved with the remanence still meeting the performance requirements of the magnetic code disk. High-resolution transmission electron microscopy (HRTEM) analysis reveals that diffused Pt atoms can facilitate the formation of a small amount of non-magnetic γ-FeCrCo phase, which has a pinning effect on magnetic domain walls, thus significantly increasing the coercivity of the FeCrCo film. Moreover, since the γ-FeCrCo phase and the α-FeCrCo phase have similar crystal lattices, material uniformity can be maintained, which is beneficial for ensuring the uniformity of output signals of the code disk with small magnetic pole pitches.

Simulation and experimental study on surface modification of 6061‐T651 aluminum alloy by machine hammer peening

AbstractMachine hammer peening is a surface treatment technique employed to enhance the surface properties of the treated samples. In this present work, the theoretical analysis, finite element simulation and experiment of single peening are carried out to investigate the relationship between the machine hammer peening force and geometric dimensions of the single peening indentation deformation, including diameter and depth. The single peening experimental results are in accordance with theoretical and simulation analysis. The machine hammer peening experiment with grate tool path are done and the results including surface topography, surface roughness, surface hardness, x‐ray diffraction analysis and wear resistance are discussed. This work seeks to explore the effects of process parameters like machine hammer peening force, indentation and pitch spacing on surface roughness and hardness. The results reveal that the surface hardness and roughness are positively associated with machine hammer peening force and small indentation and pitch spacing lead to high hardness. The x‐ray diffraction analysis validate machine hammer peening is a mechanical treatment without new compound generated. The friction test results in an enhancement in wear resistance of treated samples.

Viewpoint-dependent lighting on polygonal holograms using bump mapping.

Holograms can be observed from different viewpoints, because light waves can be encoded to propagate in multiple directions. Thus, accurate holograms for 3D display should model viewpoint-dependent light reflections. We proposed a new, to the best of our knowledge, hologram generation method for objects represented by polygonal meshes, whose lighting changes as the viewer moves, all while rendering smooth shading using low-poly objects. The proposed method leverages bump mapping and converts it into a bump-phase map encoding the propagation frequency and then spreads the reflected light wave so that only a specific viewpoint can receive them. Simulation experiments with small pixel pitches confirm the method's high computational performance.

Overview of the first Wendelstein 7-X long pulse campaign with fully water-cooled plasma facing components

After a long device enhancement phase, scientific operation resumed in 2022. The main new device components are the water cooling of all plasma facing components and the new water-cooled high heat flux divertor units. Water cooling allowed for the first long-pulse operation campaign. A maximum discharge length of 8 min was achieved with a total heating energy of 1.3 GJ. Safe divertor operation was demonstrated in attached and detached mode. Stable detachment is readily achieved in some magnetic configurations but requires impurity seeding in configurations with small magnetic pitch angle within the edge islands. Progress was made in the characterization of transport mechanisms across edge magnetic islands: Measurement of the potential distribution and flow pattern reveals that the islands are associated with a strong poloidal drift, which leads to rapid convection of energy and particles from the last closed flux surface into the scrape-off layer. Using the upgraded plasma heating systems, advanced heating scenarios were developed, which provide improved energy confinement comparable to the scenario, in which the record triple product for stellarators was achieved in the previous operation campaign. However, a magnetic configuration-dependent critical heating power limit of the electron cyclotron resonance heating was observed. Exceeding the respective power limit leads to a degradation of the confinement.

In-silico study of the impact of system design parameters on microcalcification detection in wide-angle digital breast tomosynthesis.

Accurate detection of microcalcifications ( ) is crucial for the early detection of breast cancer. Some clinical studies have indicated that digital breast tomosynthesis (DBT) systems with a wide angular range have inferior detectability compared with those with a narrow angular range. This study aims to (1)provide guidance for optimizing wide-angle (WA) DBT for improving detectability and (2)prioritize key optimization factors. An in-silico DBT pipeline was constructed to evaluate detectability of a WA DBT system under various imaging conditions: focal spot motion (FSM), angular dose distribution (ADS), detector pixel pitch, and detector electronic noise (EN). Images were simulated using a digital anthropomorphic breast phantom inserted with clusters. Evaluation metrics included the signal-to-noise ratio (SNR) of the filtered channel observer and the area under the receiver operator curve (AUC) of multiple-reader multiple-case analysis. Results showed that FSM degraded sharpness and decreased the SNR and AUC by 5.2% and 1.8%, respectively. Non-uniform ADS increased the SNR by 62.8% and the AUC by 10.2% for filtered backprojection reconstruction with a typical clinical filter setting. When EN decreased from 2000 to 200 electrons, the SNR and AUC increased by 21.6% and 5.0%, respectively. Decreasing the detector pixel pitch from 85 to improved the SNR and AUC by 55.6% and 7.5%, respectively. The combined improvement of a pixel pitch and EN200 was 89.2% in the SNR and 12.8% in the AUC. Based on the magnitude of impact, the priority for enhancing detectability in WA DBT is as follows: (1)utilizing detectors with a small pixel pitch and low EN level, (2)allocating a higher dose to central projections, and (3)reducing FSM. The results from this study can potentially provide guidance for DBT system optimization in the future.

Tilt-X: Development of a Pitch-Axis Tiltrotor Quadcopter for Maximizing Horizontal Pulling Force and Yaw Moment

In recent years, there has been a significant amount of research on tiltrotor multicopter unmanned aerial vehicles (TM-UAVs) in aerial robotics. Despite the varying frame types of TM-UAVs, they all still aim to decouple the propeller from the body, which means that the propeller’s attitude control is independent of the body’s attitude control. On the one hand, this solves the issue of multicopter unmanned aerial vehicles (M-UAVs) being limited by small roll and pitch angles, thereby improving flight performance. On the other hand, it addresses the drawbacks of M-UAVs as typical underactuated systems. However, the fact still remains that it cannot significantly change thrust direction, thus providing the necessary wrench direction for aerial manipulation. This paper presents a pitch-axis tiltrotor quadcopter unmanned aerial vehicle (UAV) design named Tilt-X, which can maximize horizontal pulling force and yaw moment when used as an aerial manipulator. This design contributes to tasks such as pushing, pulling, and twisting. The reliability of the design has been demonstrated through dynamic modeling and experimental validation.

Use of Electron Beam-Induced Current Technique to Characterize Transport Properties of Narrow-Gap-Energy Materials for IR Detection

The electron beam-induced current technique (EBIC) developed at CEA-Leti has been a valuable tool for studying the transport properties of minority carriers in HdCdTe. Indeed, previous work has demonstrated the use of this technique for estimating diffusion length from the exponential decay of EBIC as a function of junction distance, as well as direct measurement of the modulation transfer function (MTF) of small pixel pitch diodes. In this work, a modulated electron beam and a lock-in amplifier are used to measure the variation in current and phase shift with the scan distance to the junction. This work is focused on the estimation of the minority carrier lifetime from the linear evolution of the phase shift as a function of junction distance.

High-resolution 3D ultrasonic imaging using high-frequency piezoelectric transmitter and ultra-multiple laser 2D scanning

In this paper, we extend a piezoelectric and laser ultrasonic system (PLUS) to a high-frequency version for high-sensitivity three-dimensional (3D) ultrasonic imaging by utilizing a unique characteristic of PLUS. PLUS combines a piezoelectric transmitter and a two-dimensional (2D) scan of a laser Doppler vibrometer (LDV). A high frequency can be used simply by adopting a high-frequency piezoelectric transmitter with a center frequency, such as 15 MHz, since the LDV has a broad bandwidth reception of 0–25 MHz. Furthermore, a 2D array receiver with a small interelement pitch can be achieved by precisely scanning a small laser irradiation spot. We experimentally demonstrate its 3D imaging capability for flat-bottom-hole and fatigue-crack specimens.

On the Lock-In Phenomena near the Transonic Buffet Onset of a Prescribed Pitching Airfoil

The limit cycle oscillation (LCO) in the transonic buffet on the fixed supercritical airfoil OAT15A under Ma = 0.73, AoA = 3.5° and Re≈3×106, is successfully simulated by means of the Reynolds Stress Model. Further, the buffet lock-in phenomena under prescribed pitch conditions near the buffet onset are also studied by evaluating the modified energy exchange based on the pitching component of the moment coefficients as well as the normalized relative phase map between the pitching component of the moment coefficients and the airfoil’s angular velocity. The zero energy transfer branches in the modified energy map fail to indicate the lock-in boundaries, while the normalized phase map generally outlines the lock-in boundaries for small pitch amplitudes near the buffet onset, which suggests that the lock-in occurs where the moment is in phase with the angular velocity at small pitch amplitudes near the buffet onset. For pitch amplitudes larger than 0.4°, the lock-in onset deviates from the phase shift, possibly due to the fact the instantaneous angle of attack can be lower than the buffet onset where the buffet phenomena may vanish.

11‐1: Invited Paper: MicroLED Displays for Augmented Reality Smart Glasses

Augmented reality smart glasses, in general, have highest requirements as compared with smart phones and watches. Its display must be of light weight (a few grams), tremendous brightness (millions of nits), low power consumption (hundreds of milliwatts), and extremely small volume (a small fraction of cubic centimeter) to allow fashionable smart glass designs that would be socially and aesthetically favored by consumers. We have been focusing on micrometer‐scale native semiconductor MicroLED integration, to create miniaturized panels and projectors, which can be seamlessly integrated into the frames of the smart glasses. Among many technical aspects of microLED displays, two key parameters will be emphasized here. First, a microLED panel must be bright and efficient at the same time, especially for red microLED panel with small pixel pitch, such as 2.5 µm. Second, a microLED technology must enable reasonable reliability at a high energy density of, such as 10 watts per square centimeter. Vertically stacked native semiconductors monolithic integration, quantum dots conversion, perovskites, etc., will be discussed, in a context of facing challenges in materials and device physics and fulfilling the two requirements. In addition, an image quality correction method on the waveguide‐microLED display module will be proposed.

Power performance of a model floating wind turbine subjected to cyclic pitch motion: A wind tunnel study

Wind tunnel experiments were performed with a miniature floating wind turbine model to study the effects of cyclic pitch motion on its power performance. The cyclic pitch motion was prescribed by two key parameters: pitch frequency and amplitude. The power performance of the turbine model was investigated at a frequency range of 0.1 − 5.0Hz and an amplitude range of 0 − 30°. Both the mean and time variation of the power production were analyzed, and the effects of the pitch parameters, i.e., the pitch amplitude and frequency, were investigated and discussed. The results show a clear periodicity of power variation and its dependence on pitch frequency and amplitude. For relatively small pitch frequencies (0.5 − 3.0Hz), the mean power and periodic power variation can be predicted based on the uniform and steady flow assumption. Compared to the power output in the baseline case of no pitch dynamics, cyclic pitch motions were found to cause higher power fluctuations, which were contributed by both the pitch motion and flow turbulence. Finally, the temporal variation of the free-rotation speed, used as an indicator of available aerodynamic power, is found to be periodic when the turbine is under cyclic pitch motion. This suggests the possibility of applying dynamic rotor control strategies to maximize power production.

Cholesteric liquid crystal phase variations within nanotubes: an in-depth analysis of the influences of twist radius and molecular pitch

ABSTRACT This study investigates the self-assembly and phase transitions of cholesteric liquid crystals (CLCs) when confined in nanotubes, specifically focusing on the variations in their molecular structures. A dissipative particle dynamics method was used to investigate how the changes in helix radius ( r LC ) and pitch ( P ) affect the behaviour of the LCs. For pitches of 24, 12, and 6, the orientation order parameter ( P 2 ) showed distinct trends during cooling. Smaller helix radii resulted in isotropic to nematic to smectic phase transitions, whereas larger radii resulted in a novel smectic phase with spiral structures (Sm s ). Circumferential local-order parameters ( P 2 r and P 2 z ) were introduced to better characterise the phases, and a disordered spiral-structure phase (Sm s 2 ) with local perturbations was observed. The transitions between isotropic, nematic, and smectic phases, highlighting the influence of the pitch and helix radius, were observed from the phase diagrams. Smaller pitches and radii prevented the formation of stable structures; however, specific combinations induced characteristic spiral structures in the smectic phase. These results provide new insights into the self-assembly of confined CLCs, which have potential applications in the design of photonic devices and LC-based sensors. This study advances our understanding of phase control in quasi-one-dimensional systems and highlights the importance of molecular variations in liquid crystal behaviour.

PET Detectors Based on Multi-Resolution SiPM Arrays.

Almost all high spatial resolution positron emission tomography (PET) detectors based on pixelated scintillator arrays utilize crystal arrays with smaller pitches than photodetector arrays, leading to challenges in resolving edge crystals. To address this issue, this paper introduces a novel multi-resolution silicon photomultiplier (SiPM) array design aimed at decreasing the number of readout channels required while maintaining the crystal resolvability of the detector, especially for edge crystals. The performance of a pseudo 9 × 9 multi-resolution SiPM array, consisting of 6.47 × 6.47 mm2, 6.47 × 3.07 mm2, and 3.07 × 3.07 mm2 SiPMs, was compared to those of a pseudo 8 × 8 SiPM array with a 6.8 mm pitch, and a 16 × 16 SiPM array with a 3.4 mm pitch using a 36 × 36 LYSO array with a pitch of 1.5 mm. The large-size pseudo SiPMs were implemented by digitally grouping multiple 3.07 × 3.07 mm2 SiPMs. The flood histograms show that the edge crystal resolvability of the pseudo 9 × 9 multi-resolution SiPM array is comparable to that of the 16 × 16 SiPM array and is significantly better than that of the 8 × 8 SiPM array.

Correlations of Aerobic Capacity with External and Internal Load of Young Football Players during Small-Sided Games.

Aerobic capacity plays a crucial role in football performance, making it a focal point in training processes. Small-sided games (SSGs) are widely used in football training, but the relationship between aerobic capacity and running performance during SSGs remains unclear. The aim of this study was to investigate possible correlations between maximum oxygen uptake (VO2max) and running performance in youth football players in SSGs (4:4, 3:3, 2:2, 1:1) with three different pitch sizes per player (150, 100, 75 m2/player). Sixteen male U15 football players participated in the study. Players underwent the Yo-Yo intermittent recovery test level 1, and their VO2max was estimated based on their performance. Subsequently, players participated in SSGs wearing GPS devices to measure internal and external load. Pearson or Spearman correlation was applied for statistical analysis depending on the normal distribution of the data. The results reveal that, for 4:4 and 3:3 relationships, larger pitches led to a greater impact of aerobic capacity (total distance (TD): 4:4, 150 m2/pl, r = 0.715, p = 0.002; 100 m2/pl, r = 0.656, p = 0.006; 75 m2/pl, r = 0.586, p = 0.017). In the 2:2 relationship, the opposite was observed, with more correlations appearing on smaller pitches (TD: 2:2, 100 m2/pl, r = 0.581, p = 0.018; 75 m2/pl, r = 0.747, p < 0.001). In the 1:1 relationship, correlations with VO2max, total distance, and speed were observed only on the larger pitch. In conclusion, the aerobic capacity of young football players can influence running performance indicators in SSGs. Therefore, aerobic capacity could serve as a criterion for team composition, making SSGs more competitive. Additionally, the variation in correlations in the 2:2 relationship and their limited presence in the 1:1 relationship may be attributed to technical-tactical factors, such as increased ball contacts and one-on-one situations typically occurring in smaller setups.