Length Of Zone Research Articles

Multivariate Analyses of Shattering and Seed Yield Related Morphological Traits Reveal High Yielding Sesame Genotypes Exhibit Low Degree of Shattering

Sesame production faces substantial challenges, particularly in terms of shattering. To address this issue, sesame breeding programs focus on developing cultivars with minimized shattering. A pivotal aspect in achieving high-yielding and shatter-resistant cultivars lies in comprehending the association between shattering and traits related to seed yield. Thus, this study aimed to examine the correlation between shattering and morphological traits associated with seed yield, as well as to characterize genotypes based on seed yield and shattering related traits. This study utilized 64 sesame genotypes, employing an 8 x 8 simple lattice design. The study revealed significant positive correlations between shattering and the duration from capsule opening to maturity, as well as the length of cracking on opened capsules. Notably, shattering exhibits a negative correlation with seed yield related morphological traits, such as plant height and branches, suggesting taller genotypes with more branches experience lower shattering. Similarly, shattering-related traits showed a significant negative correlation with yield related morphological traits. This study advocates selecting sesame genotypes with reduced shattering while maintaining high-yielding characteristics. Principal Component Analysis (PCA) of sesame genotypes reveals essential insights, with the first four components explaining 72.90% of the total variation. Seed yield and related traits contribute significantly to PC1, emphasizing their importance in explaining variability. Capsule length, shattering (%) and days from capsule opening to maturity have large scores on PC2. PCA confirmed genotypic differences, aiding breeders in selecting high-yielding, low-shattering varieties like AsARC-acc-SG-013 for future breeding programs. Cluster analysis grouped the 64 sesame genotypes into two clusters, where Cluster I and Cluster II represent 40.62% and 59.38% of the total genotypes, respectively. Cluster analysis identifies traits distinguishing Cluster I from II, including plant height, branches, capsules, capsule-bearing zone length, seed yield, and shattering-related traits. Genotypes belonging to Cluster I exhibit superiority for desirable traits.

Effect of quadratically varying electric potential on the multiple cracks in piezoelectric materials

A basic solution to the problem of three collinear equal cracks in a transversely isotropic piezoelectric material plate is obtained under the influence of electromechanical forces. Stroh formalism and complex variable methods are used to derive the mathematical expressions for SIF (stress intensity factor), COD (crack opening displacement), and COP (crack opening potential). The length of the saturation zones is investigated at each crack tip under the influence of quadratically varying electric displacement. Furthermore, a numerical study is carried out to discuss the effect of quadratically varying electrical potential on the saturation zone, COD, and COP. The results obtained numerically are reported graphically.

Recovery and concentration of Eu(III) from phosphogypsum leachate using ouricuri endocarp

Ouricuri endocarp was utilized as a biosorbent for the recovery of europium (Eu(III)) from aqueous solutions and rare earth elements (REEs) from authentic leachate derived from phosphogypsum, which encompasses various REEs. Various characterization techniques were applied to analyze the physicochemical and adsorptive properties of the biosorbent. The results indicate that the adsorption kinetic data conform well to the pseudo-first-order model, while the Liu model describes the equilibrium data well. Ouricuri endocarp and Eu interactions are favorable and spontaneous. The maximum adsorption capacity for Eu(III) is determined to be 22.9 mg/g according to the Liu model. Based on experimental results and adsorbent characteristics, the proposed adsorption mechanisms between ouricuri endocarp and Eu include ion exchange and electrostatic interactions as the primary mechanisms. The Eu(III) recovery is also feasible as a continuous flow process demonstrating inclined breakthrough curves and lower values of the length of the mass transfer zone. Ouricuri endocarp demonstrates its selectivity for recovering various REEs from authentic phosphogypsum leachate. It achieves a 98% recovery rate for Eu and approximately 60% for Ce, La, and Nd, affirming its efficacy under real-world conditions. Finally, concentration of REE was done by ashing loaded ouricuri endocarp, and a solid with around 34% (in weight) of REE is obtained.

Simulation study on the flow characteristic and combustion performance in a high-temperature rise combustor based on RQL under different length of quench zone

Simulation study on the flow characteristic and combustion performance in a high-temperature rise combustor based on RQL under different length of quench zone

SIMULATION AND EX VIVO EXPERIMENTAL STUDY OF MICROWAVE ABLATION OF ADRENAL ADENOMA BY COAXIAL SLOT ANTENNA

Object: Microwave ablation has been widely used in tumor treatment, and the antenna is a critical component of microwave ablation. We aimed to evaluate a single-slot antenna to generate a small volume ablation zone ([Formula: see text] in adrenal tissue. Methods: A three-dimensional numerical model of the adrenal tissue was built and solved by the Finite Element Method. In the simulation model, the slot antenna was placed between the adrenal gland and fat, and the microwave ablation power and time were adjusted to obtain the target ablation zone. In ex vivo experiments, the length and width of the ablation zone were measured, and the significance of ablation parameters on it was determined using a multi-factorial analysis of variance method. The temperature versus time curves at 3[Formula: see text]mm and 7[Formula: see text]mm from the antenna were plotted to validate the simulation. Results: The simulation results showed that the combination of microwave ablation parameter settings 30[Formula: see text]W/300[Formula: see text]s, 40[Formula: see text]W/180[Formula: see text]s, and 40[Formula: see text]W/300[Formula: see text]s could create ablation zones in the adrenal tissue volumes of [Formula: see text] and [Formula: see text], respectively, with minimal damage (less than [Formula: see text] to the surrounding fat tissue. Both power and heating time significantly affected the length and width of the ablation zone. The temperature rise curves obtained in the simulation and ex vivo experiments were in good agreement. Conclusion: This work shows that utilizing a slot antenna can produce a small volume ablation zone in adrenal tissue for microwave ablation of benign adrenal adenomas.

Determining the optimal distal resection margin in rectal cancer patients by imaging of large pathological sections: An experimental study.

To determine the distal resection margin in sphincter-sparing surgery in patients with low rectal cancer based on imaging of large pathological sections. Patients who underwent sphincter-sparing surgery for ultralow rectal cancer at Guangxi Medical University Cancer Hospital within the period from January 2016 to March 2022 were tracked and observed. The clinical and pathological data of the patients were collected and analyzed. The EVOS fluorescence automatic cell imaging system was used for imaging large pathological sections. Follow-up patient data were acquired mainly by sending the patients letters and contacting them via phone calls, and during outpatient visits. A total of 46 patients (25 males, 21 females) aged 27 to 86 years participated in the present study. Regarding clinical staging, there were 9, 10, 16, and 10 cases with stages I, II, III, and IV low rectal cancer, respectively. The surgical time was 273.82 ± 111.51 minutes, the blood loss was 123.78 ± 150.91 mL, the postoperative exhaust time was 3.67 ± 1.85 days, and the postoperative discharge time was 10.36 ± 5.41 days. There were 8 patients with complications, including 3 cases of pulmonary infection, 2 cases of intestinal obstruction, one case of pleural effusion, and one case of stoma necrosis. The longest and shortest distal resection margins (distances between the cutting edges and the tumor edges) were 3 cm and 1 cm, respectively. The minimum length of the extension areas of the tumor lesions in the 46 images of large pathological sections was 0.1 mm, and the maximum length was 15 mm. Among the tumor lesions, 91.30% (42/46) had an extension area length of ≤5 mm, and 97.83% (45/46) had an extension area length of ≤10 mm. The length of the extension zone was not related to clinical pathological parameters (P > .05). In the vast majority of cases, the distal resection margin was at least 1 cm; thus, "No Evidence of Disease" could have been achieved. Additional high-powered randomized trials are needed to confirm the results of the present study.

Pressure propagation mechanism of open-cell aluminium foam within a pipe under hypervelocity impact

Low-density open-cell aluminium (Al) foam exhibits a different deformation mode under hypervelocity impacts compared to being subjected to medium-low speed and quasi-static compression. In this case, material flows between cells in the form of metal jets and propagates forward. This paper establishes the open-cell Al foam model based on Voronoi tessellation. Using numerical methods, one-dimensional hypervelocity constant velocity impact experiments of 1–6 km/s inside a closed pipe are conducted on Al foam with different internal structure parameters (average cell diameter: 2–3.5 mm; ligament width: 0.251–1 mm). Propagation mechanism of pressure waves in foams and the key factors affecting the propagation velocity are investigated. Three zones are divided according to the condition of jet distribution along the impact direction: unaffected zone, jet influence zone, and particle accumulation zone. The variation of the length of different zones with impact velocity is discussed: higher velocities result in longer jet influence zones but shorter particle accumulation zones. Meanwhile, length of zones is closely related to the width of Al foam ligament and cell pore diameter: the larger the diameter of cell pores and the smaller the width of ligaments, the longer the length of the jet influence zone. Time dependence is exhibited in the length of jet influence zone for the large cell pore diameter specimens(≥0.03 cm). Particle pressures are extracted using the one-dimensional averaging method, which propagates forward significantly lower than in dense materials. Dominant factors affecting the pressure wave propagation of open-cell Al foam, i.e., the internal unloading space, are obtained by combining two-dimensional hypervelocity impact simulation experiments with different boundary conditions. A strong correlation between metal jet distribution and particle pressure propagation is observed.

Modelling of opposed flame spread over thin electric wires: estimation of flame spread rates and limiting oxygen concentrations

A model of opposed flame spread along thin electric wires is developed to estimate the variation of flame spread rate ( V f ) with oxygen concentrations and oxidiser flow velocity. The length of pyrolysis zone ( L py ) and V f are treated as eigenvalues of the problem, and one-dimensional energy balance equations for the wire core and insulation are formulated to derive their solutions. To obtain a set of steady solutions for L py and V f , the macroscopic energy balance equation for the entire system is calculated from the one-dimensional energy balance equations with appropriate boundary conditions. Since the equations are nonlinear function of L py and V f , multiple solutions appear. The physical meaning of each solution is evaluated based on the deviation of energy from the equilibrium. Comparison of the temperature distribution along the wire with experimental data confirms that the model reproduces well the actual flame spread process. The variation of V f with oxygen concentration shows a C-shaped curve. The upper branch is the stable solution, and the lower branch is the unstable solution and the merging point of two branches correspond to the limit condition for flame spread. Therefore, the model can be used to estimate the limiting oxygen concentration based on the existence of a solution for V f . Furthermore, the variation of V f with oxidiser flow velocity shows O-shaped curve, and it is confirmed that radiative extinction under low flow velocity and blow-off under high flow velocity can also be estimated with the model. Mapping of variations of radiative extinction and blow-off extinction with oxygen concentration reveals the U-shaped flammability diagram. The predicted flame spread limits are in good agreement with the limiting oxygen concentrations measured in both microgravity and normal gravity, demonstrating the validity of using this model to predict flammability characteristics of electric wires under various oxidiser flow velocity.

In-situ separation of natural gas hydrates and sediment backfilling

Natural Gas Hydrates (NGH) offer a promising solution to the global energy shortage. Nevertheless, the extraction of NGH encounters complexities and challenges in marine environments, necessitating the systematic separation of seawater, NGH particles, and sand, as well as the backfilling of sand to prevent damage to the seabed geological structure. Leveraging computational fluid dynamics (CFD) studies on operational and structural parameters, we have developed an optimized Axial Annulus In-situ Hydrocyclone Desander (AAIHD-2). By enhancing the radial forces exerted and extending the suspension time of particles within the flow field, the separation efficiencies of sand and NGH reached 84.7 % and 76.1 %, respectively. Increasing the length of the separation zone proves advantageous in boosting the separation efficiency of both sand and NGH. Notably, while the sand separation efficiency increases with higher flow rate, the NGH separation efficiency decreases. AAIHD-2 exhibits a maximum pressure drop of 320.7 kPa, constituting a mere 2.1 % of the environmental pressure (15.2 MPa), thereby ensuring the preservation of NGH equilibrium throughout the extraction process. This study is poised to facilitate the efficient separation of NGH and the backfilling of sand in order to enable the safe extraction of seabed NGH.

A Study on the Conditions of Fog Generation and the Change Rule of Fog Zone Length in Air Intake Roadway

Fog in mine air intake roadways is a non-negligible disaster that seriously reduces the visibility of the roadway, affects vehicle transportation and the safe passage of personnel, and jeopardizes the safe production of the mine. This paper applies both field testing and numerical simulation to explore fog formation conditions and the effects of inlet air temperature and humidity on the fog zone length within the Wangjialing Mine’s air intake roadway in Shanxi, China. First, based on the consideration of the relationship between the moisture gain of surrounding rock and the temperature with humidity of the air flow, the fog generation and distribution law model of the air intake roadway was established. Based on this model, the critical inlet air temperature and the critical inlet air relative humidity for fogging in the Wangjialing Mine air intake roadway were determined. In addition, we found that the fogging point inside the roadway shifted forward continuously with the increase in inlet air temperature and inlet air relative humidity, and the length of the fog zone expands parabolically in response to these rising conditions.

Research on a work zone model with metering zone under mixed traffic flow environment

In the upstream of the highway work zone, vehicles will change lanes automatically or forcibly, which has complexity and randomness. Most studies fail to consider the impact of actual mixed traffic characteristics on traffic flow. For example, the dependence of the lane-changing behaviors of Connected and Automated Vehicles (CAVs) on the length of the zone is ignored in upstream of work zone. In addition, it is assumed that vehicles in the merge lane of the work zone would “yield” or not consider an impact on vehicles in the through lane. This simplifies the complex dynamics of the interaction between the two streams of traffic, which leads to the results of the study and the actual situation inconsistency. Based on the Gipps model, the adaptive cruise control (ACC) and the collaborative adaptive cruise control (CACC) vehicle-following models, this paper proposes a continuous cellular automata model under Vehicle-Road Collaboration and studies the mixed traffic flow characteristics in the work zone. By setting a metering zone before the lane reduction sign, ACC/CACC can adjust headway by obtaining road information in advance. The simulation results indicate that ACC/CACC vehicles have better following response compared to human-driven vehicles. In other words, the platoon composed of ACC/CACC vehicles has stability and can improve the traffic capacity of the work zone. The results of the study also found that the insertion of vehicles from adjacent lane into the ACC/CACC vehicles platoon is detrimental, especially when the penetration rate [Formula: see text] is high. Furthermore, when the length of the metering zone [Formula: see text] is set at 120–150[Formula: see text]m, it can significantly improve the road congestion in the work zone.

The effect of appendages at step on heat transfer in a backward-facing step

The current study analyzes the effect of introduction of an appendage at the step, on forced convection, in a backward-facing step. Two-dimensional turbulent flow over a backward-facing step has been tested numerically. The length and size of the recirculation zone have been observed to vary, by changing the appendage length and Reynolds number. An increase in the average Nusselt number has been observed for an increase in the Reynolds number. In this study, it has been visualized that with the introduction of the appendage, the Nusselt number increases. A vertical fin length of Ya/S = 0.5 has been found to provide the greatest improvement in the heat transfer rate. The average Nusselt number increases by three times for Ya/S = 0.5. However, the Performance Evaluation Criteria (PEC) indicates the appendage of length Ya/S = 0.3 provides consistent values. This arises as the pressure drop increases by 8.75 times for Ya/S = 0.5 when compared with unobstructed case.

The toughness of interlocking metasurfaces

Interlocking metasurfaces (ILMs) are arrays of autogenous latching unit cells patterned across a surface. These create structural joints similar to bio‐inspired suture joints but patterned over a 2D surface rather than a 1D seam. This enables ILMs to be an alternative to conventional joining technologies such as bolts, welds, and adhesives. However, compared to conventional joining methods, relatively little is known of the engineering considerations for designing structural ILMs. In this study, the interfacial toughness of an archetypal ILM was examined for the first time. Under the conditions studied here, the ILM was substantially tougher than the material from which it was made; in this case exhibiting up to a 50% increase in interfacial crack initiation energy over the solid base material, a photocured 3D printed polymer. Through experimental tests using in‐situ digital image correlation along with complementary computational analyses, the mechanism of toughening in the ILM structure and the origins of toughness anisotropy were revealed. The increase in toughness is associated with cross‐cell interactions, i.e. load‐sharing across unit cells, which gives rise to a finite process zone length with different effective material properties. In this way, ILM toughening is analogous to crack blunting in ductile materials or fiber bridging in composites; yet here, the ILM was composed of a single‐phase base material and so the architected toughening is geometric in nature and hence amenable to future topological optimization.This article is protected by copyright. All rights reserved.

Corner Vortex Structures Within Recirculation Zones of Confined Bluff-Body Flows

The vortical structures of recirculation zones in turbulent nonreacting and premixed reacting flows around confined equilateral-triangle bluff bodies are investigated using large-eddy simulations. A three-dimensional flow structure is observed within the recirculation zones of reacting and nonreacting cases; the structure includes both the “spanwise” vortices that extend the length of the recirculation zone and “corner vortex structures” that are situated adjacent to the bluff-body trailing edge and spanwise walls. The corner vortex structures enhance the mixing and residence times of fluid inside the recirculation zone. Fluid is circulated between the spanwise vortices and corner vortex structures. Corner vortex structures always appear downstream (relative to the local flow) of the boundary-layer separation location on the spanwise walls within the recirculation zone, and they are absent when boundary-layer formation on the spanwise walls is prevented. Laminar boundary-layer theory predicts the boundary-layer separation locations within ∼12% of the calculated values from the large-eddy simulations in all but one case. These results suggest that 1) boundary-layer separation on the spanwise walls is a necessary condition for the formation of corner vortex structures, and 2) boundary-layer separation on the spanwise walls is caused by an adverse pressure gradient in the recirculation zone.

Spinal cord ischemia and reinterventions following thoracic endovascular repair for acute type B aortic dissections

ObjectiveThe technical aspects of thoracic endovascular aortic repair (TEVAR) for acute type B aortic dissection (TBAD), specifically the location of proximal seal zone (PSZ) (need to cover the left subclavian artery [LSA]), distal seal zone (DSZ) (length of aortic coverage), benefit of LSA revascularization, and prophylactic lumbar drainage are still debated. Each of these issues has potential benefits but also has known risks. This study aims to identify factors associated with reintervention and spinal cord ischemia (SCI) following TEVAR for acute TBAD with a zone 3 entry tear. MethodsThe Vascular Quality Initiative was queried for TEVARs performed for acute TBAD with zone 3 entry tear, zone 3 proximal zone of disease, treated with TEVAR extending between zone 2 and zone 5. The primary outcomes were SCI and related reintervention. Secondary outcomes were stroke, arm ischemia, and retrograde type A dissection (RTAD). The exposure variables were PSZ 2 vs 3, DSZ 4 vs 5, prophylactic lumbar drain, and LSA revascularization. Univariate analyses were conducted with χ2 analysis, and multivariable logistic regression was used to evaluate association with outcomes. ResultsOf 583 patients who met inclusion criteria, 266 had PSZ 2 and 317 had PSZ 3. On univariate analysis, PSZ 2 was associated with a higher rate of reintervention, but PSZ2 was not significant on multivariable analysis after accounting for age, sex, race, smoking, PSZ, DSZ, prophylactic lumbar drain, and LSA patency. PSZ 2 was not associated with SCI, arm ischemia, or RTAD. PSZ 2 was associated with a trend towards a higher rate of stroke. DSZ 4 and DSZ 5 were performed in 161 and 422 TEVARs, respectively, and DSZ 5 was associated with a higher rate of SCI on univariate (3 [1.9%] vs 39 [9.2%]; P = .01) and multivariable (odds ratio, 7.384; 95% confidence interval, 2.193-24.867; P = .001) analyses. Prophylactic lumbar drain placement was not statistically significantly associated with SCI, but lack of postoperative LSA patency was associated with SCI (odds ratio, 2.966; 95% confidence interval, 1.016-8.656; P = .05). ConclusionsThis study found that PSZ 2 was not associated with lower reinterventions or higher rates of SCI but trended towards a higher rate of stroke than PSZ 3. Additionally, DSZ 5 was strongly associated with SCI when compared with DSZ 4, highlighting the importance of limiting aortic coverage to coverage of the proximal entry tear when possible.

Dam‐induced difference of fish habitat distribution in the fluctuating backwater zone of the Three Gorges Dam

AbstractChanges in fish habitat induced by dam construction in the downstream river have been well documented in an increasing body of literature. Fish habitats in the backwater zone of dams have undergone dramatic changes, which have still remained poorly understood. This study aims to provide a more complete understanding of fish habitat distribution and clarify fish habitat utilization patterns in the upstream dam in order to adopt effective remediation activities. This study was conducted in the Three Gorges Dam (TGD) as it is the world's largest installed capacity hydropower station, with a backwater zone length of about 660 km. Four major Chinese carp (FMCC) were selected as target fish species, and fish habitat distribution upstream of TGD was assessed by integrating the swimming ability and environmental preference of different fish species into their critical life stages. Assessment results at different life stages of the target fish species showed that June was a critical period for spawning activities FMCC in the fluctuating backwater zone of TGD. The riverbank was an important feeding habitat for FMCC, and the high‐velocity flow in the centre of the channel exceeded the limits of the swimming ability of target fish. The fish habitat distribution in the fluctuating backwater zone of TGD was heavily affected by runoff from April to September and by dam operation from October to March of the next year. This work provide valuable information about river conservation and management in the upstream of TGD.

Numerical study of wave run-up on sea dikes with vegetated foreshores

Integrating coastal vegetation into sea dikes is a nature-based approach aimed at combining disaster prevention with ecological sustainability in coastal areas. This study investigates the impact of vegetation on the wave run-up on dikes through numerical analysis. The numerical model used in the study solves the Reynolds-averaged Navier–Stokes equations by adding a vegetation resistance force to account for momentum loss. A stabilized k–ω shear stress transport model considering the vegetation effect was adopted for turbulence closure. A series of numerical simulations was carried out on the wave run-up (Ru) on dikes, focusing on the effects of different vegetation heights, densities, zone lengths, and dike slopes under various wave conditions. The results indicate that vegetation can significantly decrease Ru and may cause the wave to change from breaking to nonbreaking on dikes. The Ru behaviors depend on whether waves break and can be well characterized by the Iribarren number and dimensionless wave momentum flux parameter under breaking and nonbreaking conditions, respectively. Finally, the multivariate non-linear regression (MNLR) and artificial neural network (ANN) methods were adopted to explore a prediction model for evaluating Ru. Comparisons showed that the prediction performance of the ANN model is superior to that of the MNLR model. The ANN model has the potential as a promising predictive tool for obtaining wave run-up on dikes with vegetated foreshores under breaking and nonbreaking conditions.

Method for identifying the position of crack tip by displacement distribution based on digital image correlation

Determining the position of crack tip is crucial for rock fracture characteristic analysis. This study aims to establish a quantitative standard for determining crack tip positions in crystalline rocks based on digital image correlation (DIC). Semi-circular bending (SCB) tests were conducted on four types of rocks under three-point bending. Optical microscopy and DIC were used to investigate characteristics of the horizontal displacement fields around the crack tips. A significant disparity in the displacement gradient was observed across the crack tips, with the internal gradient being approximately 3–5.1 times higher than the external gradient. A critical value ranging from 0.41%–0.64% was determined for the high internal displacement gradient (∂u/∂x) at a 20 pixel resolution equivalent to 1 mm. Furthermore, a novel DIC-based method was proposed that used three patterns of opening displacement gradients to classify SCB specimens into non-cohesive, cohesive, and elastic zones, providing a quantitative determination of Type I crack tip positions. This study offers valuable insights and a crack tip determination method based on DIC gradients, applicable for assessing parameters such as the crack extension length and fracture process zone length.

Late Quaternary Surface Displacements on Accretionary Wedge Splay Faults in the Cascadia Subduction Zone: Implications for Megathrust Rupture

Because splay faults branch at a steep dip angle from the plate-boundary décollement in an accretionary wedge, their coseismic displacement can potentially result in larger tsunamis with distinct characteristics compared to megathrust-only fault ruptures, posing an enhanced hazard to coastal communities. Elsewhere, there is evidence of coseismic slip on splay faults during many of the largest subduction zone earthquakes, but our understanding of potentially active splay faults and their hazards at the Cascadia subduction zone remains limited. To identify the most recently active splay faults at Cascadia, we conduct stratigraphic and structural interpretations of near-surface deformation in the outer accretionary wedge for the ~400 km along-strike length of the landward vergence zone. We analyze recently acquired high-frequency sparker seismic data and crustal-scale multi-channel seismic data to examine the record of deformation in shallow slope basins and the upper ~1 km of the surrounding accreted sediments and to investigate linkages to deeper décollement structure. We present a new fault map for widest, most completely locked portion of Cascadia from 45 to 48°N latitude, which documents the distribution of faults that show clear evidence of recent late Quaternary activity. We find widespread evidence for active splay faulting up to 30 km landward of the deformation front, in what we define as the active domain, and diminished fault activity landward outside of this zone. The abundance of surface-deforming splay faults in the active outer wedge domain suggests Cascadia megathrust events may commonly host distributed shallow rupture on multiple splay faults located within 30 km of the deformation front.

Identifying some regularities of the turbulent steady-state plane-parallel motion of incompressible fluid at the entrance length

This paper investigates the structural changes in the turbulent motion of an incompressible fluid in the hydrodynamic entrance region of plane-parallel pressure motion. Movement in pressure hydromechanical systems usually occurs in a turbulent regime. Studying the patterns of changes in hydrodynamic parameters under conditions of stationary turbulent pressure motion in the inlet region is a very urgent task. The study was carried out on the basis of boundary layer equations. Taking into account the dependence of changes in the kinematic viscosity coefficient that occur between layers of fluid, a boundary value problem was formed. Analytical solutions have been obtained that make it possible to obtain patterns of changes in velocity and pressure in any effective flow section. Based on the general conclusions of the study, solutions were found for two cases: a) the velocity of the fluid entering the cylindrical pipe is constant; b) the velocity of the incoming fluid has a parabolic distribution. For these cases, using computer analysis of the data obtained, general graphs of velocity changes were constructed in various sections along the hydrodynamic entrance region. These graphs, which display the change in velocity along the entire length of the inlet, make it possible to obtain the velocity of fluid movement at any point along the inlet length and estimate the length of the transition zone. The results obtained are among the least studied issues of classical fluid mechanics and are of important theoretical interest. The results obtained are applicable for the correct construction of the hydrodynamic entrance region of machinery. A calculation formula has been obtained to determine the length of the hydrodynamic inlet region