Suction Mechanism Research Articles

METHODOLOGY FOR CALCULATING THE ENERGY SUPPLY SYSTEM FOR REPAIR PRODUCTION SITES OF DOUGH DIVIDERS OF A VACUUM PISTON TYPE

The efficiency of vacuum-piston type dough dividing machines is determined by the suction mechanism of the dividing device, when the parts of which are worn out, vacuum loss occurs due to which the accuracy of the dough weight is violated. The most promising method of restoring worn surfaces of parts of the suction mechanism is electric spark treatment. (Research purpose) The research purpose is developing a repair site for dough-dividing machines with the restoration of parts by the method of electric spark processing and proposing a methodology for calculating the energy supply system. (Materials and methods) Recommended the route of the technological process for the repair of dough dividing machines, which consists of the following operations: washing, defect, locksmith, mechanical, surfacing and control. The analysis of the process under consideration at the site showed that the health of the worker is affected by a complex of harmful production factors, such as noise, vibrations, dustiness, light exposure, release of chemicals into the air of the working area. Performed in the process of experimental research with the help of modern high-precision instruments measuring the level of indicators of these factors at the repair site of dough dividing machines. (Results and discussion) Measurements in the conditions of the implementation of the technological process allowed us to draw the following conclusions: the noise and vibration level is below the maximum permissible; air pollution is twice as high as the maximum permissible concentration. It was recommended, based on the data obtained, to provide workers with overalls and personal protective equipment. Using the example of supply and exhaust ventilation, we calculated the choice of technical parameters of the electric motor and ventilation ducts. It was noted that the introduction of the proposed energy supply system significantly reduces the level of harmful impurities in the air to optimal and acceptable values and eliminates serious diseases and poisoning of the human body. (Conclusions). The developed method of calculating the energy supply of production sites for the repair of dough-dividing machines allows to identify and eliminate harmful factors of the projected technological process. This technique can be used to determine dangerous and harmful factors in the design of production sites for the repair of other facilities.

Fully closed cell sorter for immune cell therapy manufacturing

By analyzing patients treated with adoptive immune cell therapies, various immune cell phenotypes have been found in the starting and infused materials as determinants of sustained remission. The isolation of these specific phenotypes for clinical use requires current Good Manufacturing Practice (cGMP)-compliant cell-sorting technologies with multiparameter selection capabilities. Here, we developed a cGMP-requirement-applicable fully closed cell sorter that has a suction mechanism and multiparameter detection using two laser optical settings. Negative pressure generated by a change in the chamber volume at a sorting point allows the isolation of cells of interest with high viability and purity. Our study demonstrated that this microfluidic sorter enables the isolation of cells of interest at an effective rate of 7,000 sorts per second on average. A purity of 85.5% and 77.1% effective yield with 93.7% viability was obtained when applying a target population of 35.9% in total (lymphocyte+CD8+) at 15,000 events per second (2×107 cells/mL). The sorted gene-modified Tcells maintain largely unaltered proliferation, antigen recognition, cytokine release, and cytotoxicity functionalities.

Peak suction on a wall-mounted square cylinder by conditional POD: Effects of incident angles

The wind incident angle (α) is one of the crucial factors that dominates the peak suction on wall-mounted square cylinders (e.g., high-rise buildings). With a focus on the incident angle effects, this study applies the conditional space–time proper orthogonal decomposition (conPOD) to investigate the temporal evolution of peak suction in a statistical sense. Local regions of peak suction are typically classified as the lower windward corner, upper windward corner, trailing-edge region, and lower central side wall, which occur at different ranges of incident angle. The results show that the occurrence of peak pressures at the upper and lower windward corners on the wall of flow separation bubble is not synchronized on average when the incident angle is smaller than the critical angle (α≈15°). However, at a greater angle, a strong correlation is observed between the two regions of peak pressures at α=15–35°. The peak suction on the lower central side wall observed when α=5–15° is verified to have the same flow mechanism (i.e., inverted conical vortex) as the lower windward corner. The location, time of occurrence, and the flow mechanism of the trailing-edge peak suction are systematically clarified at different incident angles by the conPOD method.

Assessment of Tribotechnical Properties of Consolidated Materials Obtained by Electrospark Processing

Abstract Introduction. The bakery industry is an agricultural industry of high-level processing of raw materials focuses on the end-consumer. In the production of bakery products one of the operations of the technological process is performed by dough dividers of vacuumpiston type, whose service life is 30‒40% lower than the normative. The most promising method for restoration of worn parts of the suction mechanism is electrospark processing. When selecting the electrode material, it is important that they have not only low erosion resistance, but also high tribotechnical properties. Aim of the Article. The article deals with problem of selecting electric coatings to reduce wear of working surfaces of suction mechanism parts during repair of vacuum piston-type dough dividers. Materials and Methods. The analysis of the properties of electropark coatings was carried out by nondestructive testing methods using modern research equipment; the results were processed using the Compass-3D program. Results. There are determined the values of physical, mechanical, frictional and tribotechnical properties of electrospark coatings made of BrOS10-10 bronze and Kh15N60 alloy. The total wear rate for BrOS10-10 bronze coating was 8,3 ∙ 10‒12, and for Kh15N60 alloy 15 ∙ 10‒12. Discussion and Conclusion. Total wear rate on the friction machine of bronze coated samples is lower than that of basic friction pair in 1.4 times, and of alloy coated samples ‒ higher in 1.26 times. Adding of MODENGY solid-lubricant coating to the coating from the alloy reduces its abrasion ability by 3 times, and the total wear rate ‒ by 1.34 times in comparison with the base friction pair. The used calculation-experimental method showed low wear rate of electrospark coatings of bronze and alloy in relation to the material of parts of the suction mechanism of vacuum-piston-type dough dividing machines.

Effect of particle size on the suction mechanism in granular grippers

Granular grippers are highly adaptable end-effectors that exploit the reversible jamming transition of granular materials to hold and manipulate objects. Their holding force comes from the combination of three mechanisms: frictional forces, geometrical constraints, and suction effects. In this work, we experimentally study the effect of particle size on the suction mechanism. Through X-ray computed tomography, we show that small particles (average diameter d approx {120},upmu hbox {m}) achieve higher conformation around the object than larger particles (d approx {4},hbox {mm}), thus allowing the formation of air-tight seals. When the gripper is pulled off, mimicking lifting of an object, vacuum pressure is generated in the sealed cavity at the interface gripper–object. If the particles used as filling material are too large, the gripper does not conform closely around the object, leaving gaps between the gripper’s membrane and the object. These gaps prevent the formation of sealed vacuum cavities between the object and the gripper and in turn hinder the suction mechanism from operating.Graphical abstract

Cardiac Helical Function. Fulcrum and Torsion

The aim of this study was to investigate a) the starts and ends of the continuous myocardium; b) the slippage between the myocardial segments, when performing both torsion and ventricular detorsion, implies that there should be an antifriction mechanism that avoids dissipating the energy; c) the electrical activation of the endocardial and epicardial myocardium and secondarily understand ventricular twist and the mechanism of active suction during the diastolic isovolumic phase.

Design and Development of Walking-type Power-operated Pneumatic Cotton Picker

Cotton verities do not mature at a particular time under Indian climatic conditions, for which mechanisation of cotton-picking operations is still a major problem. Development of mechanical device for selective picking of cotton is thus necessary. A walking-type power-operated pneumatic cotton picker was designed based on suction mechanism. The conceptual design of the cotton picker with major components viz., prime mover, trolley frame, aspirator, cotton collection drum, and suction pipe with picking spout was done using Pro-E wildfire 2.0 software. Field evaluation was done with 3 levels of picking spout diameter (30, 40, 50 mm) and 4 levels of aspirator speed (3000, 4000, 5000, 6000 rpm). The maximum air velocity, suction pressure, picking capacity, and picking efficiency were 13.97 m.s-1, 0.049 kg.cm-2, 9.23 kg.h-1, and 95.73%, respectively. Minimum fuel consumption of 1.35 l.h-1 was observed at aspirator speed of 3,000 rpm, and the lowest harvesting loss of 6.51% was observed with a combination of 30 mm × 6000 rpm. The savings in cost and time compared to the traditional manual method of cotton picking were 52.77% and 60%, respectively.

Load Cell Mechatronic Approach with Finite Element Analysis (FEA) in SolidWorks Design Development of a Small-Scale Egg Sorter

This research was about developing an automated small-scale egg sorting machine, equipped with mechatronic components, that can sort chicken eggs and place them in trays according to five (5) weight classifications: pewee, small, medium, large, and extra-large with the use of an Arduino load sensor. The machine was made up of a load cell sensor, an Arduino mega controller, a suction mechanism hanging from a rail system driven by a National Electrical Manufacturers Association (NEMA) stepper motor, and a set of five egg trays for the five (5) egg weight classifications. The Arduino Mega microcontroller was used to operate the machine's moving parts, pump, sensors, and LCD. The machine was equipped with an alarm system that produces a sound when the suction picks up the 13th egg of a full tray. The Finite Element Analysis (FEA) simulation was done using SolidWorks software to analyze the vacuum pump capacity and the effects of dynamic force on the eggs during the pick and place process. Testing results of the actual fabricated machine indicated that it was able to successfully weigh, pick through suction, sort, and place eggs into 2x6 trays according to weights. The accuracy was 92.55 percent.

Experimental Study on the Effects of Matric Suction on Shear Properties of Polypropylene Fiber Reinforced Unsaturated Clay.

Matric suction has an important effect on the behavior of unsaturated soils, and polypropylene fibers are often used to improve soil. In order to probe into the mechanism of matric suction and fiber reinforcement, triaxial shear tests are carried out with changing matric suction and net confining pressure. Unsaturated clay in the Shaoxing section of East Zhejiang Grand Canal is selected with polypropylene fiber as a reinforcement material in the tests. The results show that the total cohesion intercept and effective internal friction angle of soil increase with the increase in matric suction, while the adsorption internal friction angle decreases gradually. Similarly, the contribution of matric suction to shear strength decreases. The total cohesion intercept is more sensitive to matric suction. As the length of fiber is 12 mm, the shear strength parameters of soil will be improved accordingly, which makes the fiber reinforcement achieve the best. The stress-strain relationship is approximately hyperbolic and strain hardening. The characteristics of strain hardening are more obvious with the increase in matric suction, and the soil specimens present plastic failure. The volumetric strain of specimen is more sensitive to the changing net confining pressure. It increases with the increase in net confining pressure, and increases linearly as the matric suction is zero. The failure modes of triaxial tests are divided into tensile failure and friction failure.

Capturing wake capture: a 2D numerical investigation into wing–wake interaction aerodynamics

A wing generating lift leaves behind a region of disturbed air in the form of a wake. For a hovering insect, the wings must return through the wake produced by the previous half-stroke and this can have significant effects on the aerodynamic performance. This paper numerically investigates 2D wings interacting with their own wake at Reynolds numbers of 102 and 103, enabling an improved understanding of the underlying physics of the ‘wake capture’ aerodynamic mechanism of insect flight. We adopt a simple kinematic motion pattern comprised of a translational stroke motion followed by a complete stop to expose wake interaction effects. Representative stroke distance to chord ratios between 1.5 and 6.0 are considered, enabling different leading-edge vortex (LEV) attachment states. We also allow pitching rotation towards the end of stroke, leading to wake intercepting angles of 135°, 90°, and 45°, analogous to delayed, symmetric, and advanced pitching rotations of insect wings. It is shown that both vortex suction and jet flow impingement mechanisms can lead to either positive or negative effects depending on the LEV attachment state, and that stroke distances resulting in a detached/attached LEV lead to beneficial/detrimental wake interaction lift. Pitching rotation at the end of the stroke motion is found to induce a strong rotational trailing-edge vortex (RTEV). For advanced pitching, this RTEV serves to enable either a stronger flow impingement effect leading to positive wake interaction lift if the LEV is detached, or a less favourable vortex suction effect leading to negative wake interaction lift if the LEV is closely attached. The higher Reynolds number led to faster development of the wake vortices, but the primary wake interaction mechanisms remained the same for both Reynolds numbers.

217.8: How to Do It: Use of Octopus Tissue Stabilizer for Minimal Manipulation Approach of the Bronchial Anastomosis in Lung Transplant

Introduction: Bronchial anastomotic complications (BAC) are a cause of grave concern for surgeons that perform lung transplantation. There are several risk factors that may lead to this complication, being inadequate surgical technique one of them, specifically regarding the adequate exposure and manipulation of the bronchial stump and anastomosis. Method: We report the use of the Octopus Tissue Stabilizer (Medtronic, Inc, Minneapolis, MN) as a mean of allowing for a better exposure of the stump and facilitate a “no touch” approach towards the anastomosis. Results: The Octopus Tissue Stabilizer (Medtronic, Inc, Minneapolis, MN) is a validated device for cardiac surgery as a tissue stabilizer for off-pump coronary artery bypass. It utilizes vacuum at the extremity of its “U” shaped claw to soothe the beating of the heart on a designated spot and assist the cardiac surgeon. Our idea was to employ the distal claw of such device to stabilize the bronchial stump and perform the bronchial anastomosis with a “no touch” technique. As we did not have a need to smooth the beating of the heart, the suction mechanism was kept turned off (FIGURE 1). It is important to report that in this case, as in others, several other techniques were applied to reduce BAC (the use of end-to-end anastomosis and pericardial flap), therefore it is impossible to affirm that the application of the Octopus Tissue Stabilizer (Medtronic, Inc, Minneapolis, MN) is responsible for the favorable outcome of this patient. Conclusion: We believe that the systematic application of devices that facilitate the employment of the correct surgical techniques can have an effect in reducing the incidence of BAC, while providing no additional risk to the patient.

Hydrodynamics study on a traveling wave-based undulating surface of a hydrofoil in a free-stream flow

We numerically show that traveling wave-based surface-undulations on a hydrofoil generates thrust. Simulations demonstrate that the pressure suction mechanism generates thrust beyond a threshold ratio of the wave to free stream flow speed. This mechanism is reminiscent of thrust generation in whole body undulation, as seen in prior studies. Within the examined parameter space, two distinct vortex patterns are revealed: almost steady vortex-sheet and periodic vortex-street. Both forward and reverse types of vortex-sheet and vortex-street are found behind the hydrofoil.

Rotational flow and thermal behavior of ternary hybrid nanomaterials at small and high Prandtl numbers

In this study, rotational flow and heat transfer characteristics of Al2O3 + SiC + MWCNT + water composite nanofluid towards a stretched surface emplaced in a Darcy-Forchheimer medium have been investigated. Energy equation is modeled by considering radiative heat flow and viscous dissipation effects. Suction mechanism and convective boundary heating are taken into consideration. Fourth order Runge-Kutta method along with shooting approach is used to produce the appropriate numerical solution. A comparison of our findings with previous research reveals a remarkable degree of concordance. For both ternary (Al2O3, SiC and MWCNT) and unary (Al2O3) nanoparticles, relevant characteristics are described on velocity, temperature, local skin friction, and Nusselt number profiles. Numerical results conveyed that prominent decelerated flow of ternary hybrid nanofluid is attained due to amplification of rotation parameter in Darcy-Forchheimer medium subject to both low Pr(Pr = 0.01) and high Pr(Pr = 10000) than unary nanofluid. Axial velocity peters out by 11.76% (at low Pr (Pr = 0.01)) and 12.5% (at high Pr (Pr = 10000)) for ternary hybrid nanofluid (THNF) while it whittles down by 21.42% (at low Pr) and 20% (high Pr) for unary nanofluid (UNF) subject to fluid (UNF/THNF) flows in Darcy medium (Fr = 0) and non-Darcy medium (Fr = 3). In addition, heat transfer rate from the rotating surface emaciates significantly by 119% for THNF at Br = 1.5, Bi = 1 from low Pr(Pr = 0.01) to high Pr(Pr = 10000).

A Bioinspired Adhesive Sucker with Both Suction and Adhesion Mechanisms for Three-Dimensional Surfaces

There are significant advantages to investigate underwater attachments, which would be valuable in providing inspirations and design strategies for multi-functional surfaces and underwater robots. Here, an abalone-inspired sucker integrating an elastic body and a membrane structure is proposed and fabricated filled with rigid quartz particles to adjust the backing stiffness of the contact like abalone. The membrane is used to conform and contact surfaces well, the center area of which can be pulled in exposed to a negative pressure differential, to create a suction cavity. The pulling experiments indicate that the sucker can adhere to three-dimensional surfaces with both suction and adhesion mechanisms in both dry and liquid environments. The switching between soft/hard contact states leads to the change of adhesive strength over 30 times. Furthermore, we provide theoretical analysis on how the sucker work well in both dry and liquid environments. Finally, the developed sucker can easily lift up smooth planar objects and 3D objects, and can grip objects both smaller and larger than the size of the sucker, which have a difficulty for conventional suckers or friction-based grippers. The potential application of the sucker in flexible transfer robot is demonstrated on various surfaces and environments, paving the way for further bio-inspired adhesive designs for both dry and wet scenarios.

The Immediate Effects of the Manual Therapy Traction Manipulations on Parameters of Cardiorespiratory System Functioning

The aim of this study was to determine the changes in the cardiorespiratory system activity under the influence of traction manipulations in the thoracic spine. The study involved 26 adults, including 18 women aged 39.6 ± 12.1 years and 8 men aged 36.3 ± 8.3 years. The mean age of patients was 38.6 ± 11.2 years. The work used an integral method of studying the cardiorespiratory system - spiroarteriocardiorhythmography (SAKR). SACR registration was performed before and after traction manipulations in the thoracic spine directly in the procedure of manual therapy. The study of the immediate effect of traction manipulations of SMT in the thoracic spine on the cardiorespiratory system allowed establishing the main significant effects: decrease in HR (min^-1) from 85.1 (77.1; 94.2) to 79.5 (69.8; 87.6), p=0.000, decrease in duration of QTC (s) from 0.419 (0.404; 0.434) to 0.413 (0.401; 0.427), p=0.012, decrease in CO (dm³) from 5.2 (4.6; 5.8) to 4.9 (4.4; 5.6), p=0.000, SI (dm³/m²) from 3.05 (2.75; 3.30) to 2.90 (2.62; 3.20), p=0.000, increase in Vexp (L/s) from 0.28 (0.22; 0.34) to 0.31 (0.25; 0.39), p=0.030. The obtained data suggest that the main effects of traction manipulations on the thoracic spine are associated more with the changes in hemodynamic parameters of blood circulation due to activation of expiratory muscles and chest mobility, when the suction mechanisms of the chest and cardiovascular function of diaphragm are activated.

Darcy-Forchheimer flow behavior and thermal inferences with SWCNT/MWCNT suspensions due to shrinking rotating disk*

The goal of the present investigation is to explore the flow and thermal behavior of non-Newtonian fluid with single-walled carbon nanotube (SWCNT)/multi-walled carbon nanotube (MWCNT) suspensions over a shrunk rotating disk subject to Darcy-Forchheimer effect. The mechanisms of suction, viscous dissipation and thermal radiation have been implemented. Entropy generation analysis is carried on. Innovated Nayak-Shaw number is modeled and its profiles analysis are narrated in a lucid manner. Noble bv4c method cum shooting technique is instrumental to devise a requisite numerical solution of the developed system of the dimension-free boundary layer equations. The outcomes of the study include amplification of non-Newtonian parameter (Casson parameter) that controls the radial and azimuthal motions. Inclusion of a significant interfacial nanolayer upgrades the heat transfer rate that in turn provides better cooling for industrial needs. Addition of more nanoparticles and a medium with high porosity (Darcy-Forchheimer effect) contribute to the entropy minimization which is ubiquitous for the greater efficiency of specific thermal systems. Nayak-Shaw number due to the fluid friction irreversibility peters out and that due to porous medium irreversibility ameliorates with the strengthening of porosity parameter effectively. It is obvious that the contribution of porous medium irreversibility dominates over due to fluid friction irreversibility.

Cardiac Helical Function. Fulcrum and Torsion

Background: The aim of this study was to investigate: a) the starts and ends of the continuous myocardium; b) the slippage between the myocardial segments, when performing both torsion and ventricular detorsion, implies that there should be an antifriction mechanism that avoids dissipating the energy; c) the electrical activation of the endocardial and epicardial myocardium and secondarily understand ventricular twist and the mechanism of active suction during the diastolic isovolumic phase.

Active Flow Control Based Bleed in an Axial Compressor Cascade Using Large Eddy Simulation

The performance of the compressor is of great importance in developing advanced engine technology, and it dramatically influences the cycle efficiency and safety of the engine. The compressor bleed requires a part of the main flow extraction from the passage, and the removal of the airflow plays an essential role in the performance of the compressor. The influence of the constant suction and pulsed suction on the flow structures and the aerodynamic performance in a compressor cascade, and the control mechanisms are numerically studied using large eddy simulation. At a suction mass flow rate of 0.25% of the main flow rate, constant suction leads to a 9.36% reduction in Cpt, while pulsed suction gains 24% more benefit in Cpt reduction on the basis of the constant suction with an excitation frequency of 100 Hz. It indicates that the pulsed suction has more significant potential to control the loss generation in the compressor. Afterward, the flow field of the baseline, constant suction, and pulsed suction are compared to find out the flow control mechanisms of the constant suction and pulsed suction. Two different formation mechanisms of the passage vortex are found due to the excitation effect of the pulsed suction. Besides, the results of proper orthogonal decomposition and dynamic mode decomposition show that the pulsed suction can simplify and stabilize the compressor flow field, which could lead to a further benefit in Cpt.

Suction and Pulsed Blowing Applied to Local Separation Downstream of Slat Cutout

An experimental study on the application of active flow control (AFC) to a .4 scale model of a swept wing in a landing configuration was conducted. The wing is fitted with an ultrahigh bypass ratio (UHBR) engine nacelle. The highly efficient UHBR engines are characterized by a large diameter that interferes with the flow around the wing, especially with slats deflected, degrading its performance. An innovative AFC device, creating steady suction and pulsed blowing (PB), was installed in the leading-edge region of the wing, above the nacelle, and its performance was experimentally evaluated. The effects of the suction and PB mechanisms were examined individually and simultaneously using relevant normalized parameters to pave the way to a full-scale wind-tunnel test. It was shown that the AFC actuators increased lift by up to 3%, redirected the flow to the desired downstream direction, and reduced the size of the separation zone created due to the implementation of the UHBR nacelle. The next step is validating the small-scale results of this study in a full-scale wind-tunnel tests that would be the last step before the technology is flight test ready.

Analysis of pulsed suction flow control behavior based on a nonlinear reduced-order model

The use of pulsed suction is an effective unsteady flow control method. However, compared with steady suction, which simply eliminates low-energy boundary layer, pulsed suction flow control presents unique phenomena and complex control mechanisms that are not explained fully. Thus, in this paper, pulsed suction flow control in a compressor cascade is investigated by numerical simulation. Numerical results show that the control performance depends on the suction frequency, momentum, and location, as any unsteady active flow control method. To further reveal the mechanism and explain the phenomena of pulsed suction, a nonlinear reduced-order model for pulsed suction flow control is established on the basis of the Navier–Stokes equation, Stuart vortex row model, Oseen vortex model, and Stuart–Landau equation. The entrainment degree and maximal Lyapunov exponent are used as indices to evaluate the flow losses and control performance in this model. By solving the equations of this model under different parameters, the model presents similar phenomena as found in the numerical simulations with various suction frequencies, momentum, and locations. Thus, it is innovative that the model with calibrated parameters has the ability to roughly predict control performance of unsteady pulsed suction in an efficient way. Also, based on this reduced-order model, one can explain that, unlike steady suction, chaos control, momentum transfer and lock-in mechanisms are especially relevant with the control physics of pulsed suction.