bend angle
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Foods ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 148
Author(s):  
Stephanie Lam ◽  
Bethany Uttaro ◽  
Benjamin M. Bohrer ◽  
Marcio Duarte ◽  
Manuel Juárez

Commercial technologies for assessing meat quality may be useful for performing early in-line belly firmness classification. This study used 207 pork carcasses to measure predicted iodine value (IV) at the clear plate region of the carcass with an in-line near-infrared probe (NitFomTM), calculated IV of belly fat using wet chemistry methods, determined the belly bend angle (an objective method to measure belly firmness), and took dimensional belly measurements. A regression analysis revealed that NitFomTM predicted IV (R2 = 0.40) and belly fat calculated IV (R2 = 0.52) separately contributed to the partial variation of belly bend angle. By testing different NitFomTM IV classification thresholds, classifying soft bellies in the 15th percentile resulted in 5.31% false negatives, 5.31% false positives, and 89.38% correctly classified soft and firm bellies. Similar results were observed when the classification was based on belly fat IV calculated from chemically analyzed fatty acid composition. By reducing the level of stringency on the percentile of the classification threshold, an increase in false positives and decrease in false negatives was observed. This study suggests the IV predicted using the NitFomTM may be useful for early in-line presorting of carcasses based on expected belly firmness, which could optimize profitability by allocating carcasses to specific cutout specifications.


2021 ◽  
Vol 21 (4) ◽  
pp. 240-258
Author(s):  
Abdul Sattar Jawad Mohammed ◽  
Akeel Asie Nazzal

One remediation to output power drop of a gas turbine generating units during hot climates is reducing compressor inlet air temperature using fogging technique incorporating water injection into the airstream. The inlet air ductworks often include a bend or curved duct before the compressor comprising the secondary flow utilized to enhance the mixing between air and water droplets. This study investigates the effect of changing the bend angle on the resultant evaporative cooling of steadily flowing airstream. The experiments were conducted with an average air velocity range from (2.5 to 5 m/s) through (50) cm square duct. The study considered three bend angles of (45°, 90° and 135°) along with three sets of nozzle tilt angles of (- 45o, 0° and 45° ) to the axial flow direction. The results reveal that best evaporative cooling was achieved at a bend angle of (135°) when the water is axially injected, i.e., at (0o) to flow direction. These conditions were obtained at the velocity of (2.5 m/s), giving enough residence time for the injected droplets to evaporate and cool the airstream.


Author(s):  
Manish Kumar ◽  
Pronab Roy ◽  
Kallol Khan

The present paper determines collapse moments of pressurized 30°–180° pipe bends incorporated with initial geometric imperfection under out-of-plane bending moment. Extensive finite element analyses are carried out considering material as well as geometric nonlinearity. The twice-elastic-slope method is used to determine collapse moment. The results show that initial imperfection produces significant change in collapse moment for unpressurized pipe bends and pipe bends applied to higher internal pressure. The application of internal pressure produces stiffening effect to pipe bends which increases collapse moment up to a certain limit and with further increase in pressure, collapse moment decreases. The bend angle effect on collapse moment reduces with the increase in internal pressure and bend radius. Based on finite element results, collapse moment equations are formed as a function of the pipe bend geometry parameters, initial geometric imperfection, bend angle, and internal pressure for elastic-perfectly plastic material models.


2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Mohammad Athar ◽  
M.K. Sabiree ◽  
H. Athar

Lots of work regarding the scour around bridge piers in straight channelhave been done in the past by many researchers. Many factors which affectscour around piers such as shape of piers, size, positioning and orientationetc. have been studied in detail by them. However, similar studies inmeandering channels are scanty. Very few researchers have studied theeffect of angular displacement which has considerable effects of scouraround bridge piers.In this paper an attempt has been made to carry out a detailed study ofangular displacement on scour. A constant diameter bridge pier of circularshape has been tested in a meandering channel bend with bend angle as 800 .The test bed was prepared by using uniform sand having d50 as 0.27 mmand run was taken for a discharge of 2.5 l/s.


Author(s):  
Taekwang Ha ◽  
Torgeir Welo ◽  
Geir Ringen ◽  
Jyhwen Wang

Abstract Rotary draw bending is a commonly used metal forming technique for profile bending. Due to the elastic recovery of the material, springback compensation to control the bent product quality is one of the critical manufacturing issues. The realized bend angle has to be measured for springback compensation before removing the profile from the machine, and the bending process can follow an iterative approach until the product quality is satisfied. However, this trial-and-error is costly for batch production in manufacturing. An on-machine measurement technique is therefore developed to measure springback in rotary draw bending with an affordable laser and a webcam. An image processing technology is integrated with the manufacturing process to track the deformation and measure springback angle in real time, eliminating the need for the workpiece to be transferred to a measurement device. In this paper, bending experiments were conducted with AA6082 rectangular hollow profiles bent at 30°, 45°, 60°, and 90° angles, and springback angles from the conventional manual measurement were compared to that from the on-machine measurement. Since the difference in springback measurement between the proposed and the conventional methods was within 0.15° on average, it is demonstrated that the laser tracking, on-machine measurement is a feasible real-time springback measurement technique for Industry 4.0.


2021 ◽  
Vol 9 ◽  
Author(s):  
Muhammad Wasif ◽  
◽  
Anis Fatima ◽  
Syed Amir Iqbal ◽  
Muhammad Tufail ◽  
...  

Influences of thickness, width, bend angle, applied load and holding time are evaluated over the springback in hot-rolled, high-tensile strength sheet-metals (JSH-440). Blanks' thickness, width and bend angles are considered the geometric parameters, whereas applied load and holding time are the process parameters considered in the research. Analysis of variance (ANOVA) and sensitivity analysis are applied to evaluate the significance of the factors over the springback magnitude. Analytical models are developed to predict the springback in the sheet metals for the desired geometric and process parameters. Simplified analytical models are also developed for different geometries of sheet metals. Finally, the Genetic Algorithm has also been applied to determine the optimal process parameters for the minimum springback with varying geometries of the sheet metals. Finally, the influence of parameters and optimized results are discussed in detail.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
R. Silambarasan ◽  
V.R. Veerappan ◽  
S. Shanmugam

Purpose The purpose of this paper is to quantify the combined effect of shape distortion and bend angle on the collapse loads of pipe bends exposed to internal pressure and in-plane closing bending moment. Non-linear finite element analysis with large displacement theory was performed considering the pipe bend material to be elastic perfectly plastic. Design/methodology/approach One half of the pipe bend model was built in ABAQUS. Shape distortion, namely, ovality (Co) and thinning (Ct), were each varied from 0% to 20% in steps of 5% and bend angle was varied from 30° to 180° in steps of 30°. Findings The findings show that ovality has a significant impact on collapse load. The effect of ovality decreases with an increase in bend angle for small thickness. The opposite effect was observed for large thickness pipe bends. The influence of ovality was more for higher bend angles. Ovality impact was almost negligible at certain internal pressure denoted as nullifying point (NP). The latter increased with an increase in pipe bend thickness and decreased with increase in pipe bend radius. For small bend angles one NP was observed where ovality impact is negligible and beyond this point the ovality effect increased. Two NPs were observed for large bend angles and ovality effect was maximum between the two NPs. Thinning yielded a minimal effect on collapse load except for small bend angles and bend radii. The influence of internal pressure on thinning was also negligible. Originality/value Influence of shape distortions and bend angle on collapse load of pipe bend exposed to internal pressure and in-plane closing bending has been not revealed in existing literature.


2021 ◽  
Author(s):  
L. D. Hashan Peiris ◽  
Andrew Plummer ◽  
Jens Roesner ◽  
Vimal Dhokia ◽  
Wesley Essink

Abstract Hydraulic manifolds are traditionally manufactured using externally drilled intersecting galleries. This results in undesirable artefacts in the flow path such as sharp corners, and dead oil volumes, and requires additional plugs to blank redundant holes. These artefacts affect flow separation, aggravate pressure-drop and reduce hydraulic stiffness. Recent advancements in additive manufacturing (AM) technology have enabled the development of additively manufactured components which provide greater freedom in channel design and routing. Galleries can provide flow paths which are smoothly curved in 3 dimensions. AM manifold geometry can be optimized to reduce size and weight. In this research, analytical expressions are sought to approximate pressure drops in complex curved flow paths, which can subsequently be used for manifold optimization. The curved flow paths are defined by polynomial splines which are then fragmented into a series of segments each defined by a bend angle and bend radius. This paper uses approximations to Computational Fluid Dynamics (CFD) results to form pressure-drop models over a range of segment bend radii and angles. These models are then used to predict the pressure drops for curved galleries used in AM manifolds. The method is applied to four example curved galleries, and provides a reasonably accurate pressure-drop prediction in each case.


2021 ◽  
Author(s):  
Wilber Lim ◽  
Ferdinando Randisi ◽  
Jonathan P. K. Doye ◽  
Ard A. Louis

AbstractThymine dimers are a major mutagenic photoproduct induced by UV radiation. While they have been the subject of extensive theoretical and experimental investigations, questions of how DNA supercoiling affects local defect properties, or, conversely, how the presence of such defects changes global supercoiled structure, are largely unexplored. Here we introduce a model of thymine dimers in the oxDNA forcefield, and validate it by comparison to melting experiments and structural measurements of the thymine dimer induced bend angle. We performed extensive molecular dynamics simulations of double-stranded DNA as a function of external twist and force. Compared to undamaged DNA, the presence of a thymine dimer lowers the supercoiling densities at which plectonemes and bubbles occur. For biologically relevant supercoiling densities and forces, thymine dimers can preferentially segregate to the tips of the plectonemes, where they enhance the probability of a localized tip-bubble. This mechanism increases the probability of highly bent and denatured states at the thymine dimer site, which may facilitate repair enzyme binding. Thymine dimer-induced tip-bubbles also pin plectonemes, which may help repair enzymes to locate damage. We hypothesize that the interplay of supercoiling and local defects plays an important role for a wider set of DNA damage repair systems.


2021 ◽  
Author(s):  
Steve Jones ◽  
Junichi Sugiura

Abstract Steerable drilling motors still dominate US shale drilling applications. Shale well construction is commonly planned with monobore vertical, high dogleg-severity (DLS) curve and lateral sections. Limitations arise in each portion of the wellbore because one single bottomhole assembly (BHA) does not provide optimal results; hence, trips are required to optimize the BHA. The main disadvantage with existing steerable drilling motors is the requirement for high bend-angle settings to drill the high DLS curve portion of the wellbore. The geometry of a high bend-angle motor is only optimal for slide drilling the curve, it is not optimal for drilling the vertical and lateral portions of the wellbore. While drilling the vertical and lateral portions of the well, surface RPM (revolutions per minute) must be limited to reduce the cyclic bending fatigue on the large external bend. Not to mention poor wellbore quality while rotary drilling with a large external bend. To overcome this issue, a new geometry design was required. The new-generation motor uses a tilted internal drive mandrel aligned with a small external bend. This combination delivers the best of both worlds, providing high DLS capability while slide drilling and high surface-RPM capability while rotary drilling (because of the small external bend). Compact embedded drilling dynamics data recorders were used to validate the dynamic improvement of the new steerable-drilling-motor geometry versus older-style geometry with large external bend. The embedded sensors recorded at-point dynamics of shock and torsional response providing detailed comparative data sets during the development phase. The new-generation steerable-drilling-motor technology utilizes point-the-bit rotary-steerable-system (RSS) methods (for example, a tilted mandrel) with conventional steerable-motor methods (for example, an external bend). The combination of the internal tilt and external bend (aligned together) provides a completely new geometry for a steerable motor. This new geometry is beneficial for high DLS sliding capability, high surface-RPM rotary drilling and improved borehole quality (slide/rotate transition and rotary mode). This new steerable drilling motor with enhanced geometry was utilized to prove delivery of vertical/curve/lateral in one run, consistent DLS through the curve and improved tracking in the lateral. The results from development testing (comparing to older-geometry motors) will be described in this paper.


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