The Effect of Impact Angle and Fall Height on Skull Fracture Patterns in Infants

2021 ◽  
Vol 143 (7) ◽  
Author(s):  
Jiawei Yan ◽  
Junyan He ◽  
Ashely Spear ◽  
Brittany Coats
Keyword(s):  
Skull Fracture ◽  
Fracture Initiation ◽  
Initiation Site ◽  
Impact Angle ◽  
Fracture Length ◽  
Fracture Initiation Site ◽  
Impact Location ◽  
Fracture Patterns ◽  
The Impact ◽  
Fall Height

Abstract Skull fracture is a common finding for both accidental and abusive head trauma in infants and young children, and may provide important clues as to the energy and directionality of the event leading to the skull fracture. However, little is understood regarding the mechanics of skull fracture in the pediatric skull, and how accidental fall parameters contribute to skull fracture patterns. The objectives of this research were to utilize a newly developed linear elastic fracture mechanics finite element model of infant skull fracture to investigate the effect of impact angle and fall height on the predictions of skull fracture patterns in infants. Nine impact angles of right parietal bone impacts were simulated from three different heights onto a rigid plate. The average ± standard deviation of the distance between the impact location and fracture initiation site was 8.0 ± 5.9 mm. Impact angle significantly affected the fracture initiation site (p < 0.0001) and orientation (p < 0.0001). A 15 deg variation in impact angle changed the initiation site up to 47 mm. The orientation of the fracture pattern was dependent on the impact location and ran either horizontal or vertical toward the ossification center of the bone. Fall height significantly affected the fracture length (p = 0.0356). Specifically, at the same impact angle, a 0.3 m increase in fall height increased the skull fracture length by 21.39 ± 34.26 mm. These data indicate that environmental variability needs to be carefully considered when evaluating infant skull fracture patterns from low-height falls.

Fracture Patterns on the Infant Porcine Skull Following Severe Blunt Impact

2010 ◽  
Author(s):  
Brian J. Powell ◽  
Nicholas V. Passalacqua ◽  
Timothy G. Baumer ◽  
Todd W. Fenton ◽  
Roger C. Haut
Keyword(s):  
Skull Fracture ◽  
Fracture Initiation ◽  
Parietal Bone ◽  
Injury Biomechanics ◽  
Skull Model ◽  
Blunt Impact ◽  
Fracture Patterns ◽  
Deformable Interface ◽  
Young Subjects ◽  
Rigid Interface

There is a 1 in 3 chance of abuse in a case where a child less than 18 months has a skull fracture [1]. The most commonly fractured site on the skull is the parietal bone, however it is currently difficult to establish the causation of injury based on the characteristics of the injury [2]. Thus, injury biomechanics are often utilized in the investigation of suspected child abuse cases [3]. Computer simulations, test dummies, and animal models are all used as aids in the assessment of skull fracture causation. For a given impact situation, a number of variables can control the pattern of skull fracture. A study by Baumer et. al assessed the effects of interface and age using an infant porcine skull model, specifically looking at the location of fracture initiation on the parietal bone [4]. This study showed that in low energy impacts fracture initiation occurs at the bone-suture boundary. Also, a deformable interface caused more fracture than a rigid interface for very young subjects. The current study was conducted to assess the effects of higher energy impacts on the patterns of fracture in this model.

scholarly journals 3D Observation of Micro-cracks as Cleavage Fracture Initiation Site in Ferrite-pearlite Steel

2017 ◽  
Vol 57 (4) ◽  
pp. 746-754 ◽  
Author(s):  
Yoshiki Nemoto ◽  
Kazuki Shibanuma ◽  
Katsuyuki Suzuki ◽  
Sunao Sadamatsu ◽  
Yoshitaka Adachi ◽  
...  
Keyword(s):  
Cleavage Fracture ◽  
Fracture Initiation ◽  
Initiation Site ◽  
Fracture Initiation Site ◽  
Micro Cracks

EFFECTS OF IMPACT LOCATION AND ANGLE OF A FLYING CROSS BAR ON THE PROTECTION OF A LONG-ROD PENETRATOR

2013 ◽  
Vol 37 (4) ◽  
pp. 1115-1125 ◽  
Author(s):  
Yo-Han Yoo ◽  
Seung Hoon Paik ◽  
Jong-Bong Kim ◽  
Hyunho Shin
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Impact Angle ◽  
Element Analysis ◽  
Impact Location ◽  
Long Rod ◽  
The Impact ◽  
Bar Diameter

Based on a finite element analysis, the performance of a flying cross bar in protecting a long-rod penetrator increases as the impact location moves toward the head of the penetrator. It also increases as the impact angle approaches right angle. The optimal impact location along the span direction of the bar varies depending on the bar diameter.

scholarly journals Numerical simulation on Crashworthiness of 105000t LNG Carrier

2021 ◽  
Vol 2083 (3) ◽  
pp. 032037
Author(s):  
Qian Sun ◽  
Jianmin Liu ◽  
Hong Zhou
Keyword(s):  
Numerical Simulation ◽  
Impact Damage ◽  
Impact Angle ◽  
Practical Significance ◽  
Structural Repair ◽  
Impact Location ◽  
Force Velocity ◽  
Finite Element Numerical Simulation ◽  
Bulbous Bow ◽  
The Impact

Abstract It is of great significance to study the crashworthiness of LNG carrier to improve its crashresistance and enhance its operation safety. In this paper, the collision process between the bulbous bow of the container ship and the side structure of the LNG ship is analyzed by using nonlinear finite element numerical simulation. Collision performance of LNG carrier and collision indicators during the collision, the impact force, velocity and displacement and energy absorption in the process of collision by changing parameters of the major velocity, impact angle and impact location and others are studied. The relevant research results have a strong practical significance for analyzing the deformation, strengthening measures and structural repair of ship side structure impact damage.

scholarly journals Numerical Investigation on the Ultimate Strength of Box Beams with Impact Damage

2020 ◽  
Author(s):  
Wei Xu ◽  
C. Guedes Soares
Keyword(s):  
Residual Stress ◽  
Ultimate Strength ◽  
Impact Damage ◽  
Ship Hulls ◽  
Four Point Bending ◽  
Impact Location ◽  
Box Beam ◽  
Box Beams ◽  
Fracture Damage ◽  
The Impact

AbstractThe objective of this paper is to study the residual ultimate strength of box beams with impact-induced damage, as a model of what may occur in ship hulls. The bottom and side plates of ship hulls can suffer denting or fracture damage due to grounding, collision and other contacts during the ship’s service life and these impact-induced damages could result in considerable strength degradation. Box beams are firstly subjected to impact loading and then four-point bending loading is imposed on the damaged structures to assess the residual strength using ANSYS/LS_DYNA. The ultimate moment and collapse modes are discussed considering the effect of impact location. The impact-induced deformation is introduced in the four-point bending simulation, and the impact-induced stress is included or not to determine the effect of residual stress and distortion after impact. It is shown that impact location has significant influence on the residual ultimate bending moment of the damaged box beam providing that the impact energy is kept constant. The collapse modes also change when the impactor strikes on different locations. Damaged hard corner and inclined neutral axes might explain the reduction of ultimate strength and diverse collapse modes. The residual stress in the box beam after impact may increase or decrease the ultimate strength depending on impact location.

Trajectory shaping guidance law design using constraint-combining multiplier

2021 ◽  
pp. 095441002098637
Author(s):  
Min-Guk Seo ◽  
Chang-Hun Lee ◽  
Tae-Hun Kim
Keyword(s):  
Design Method ◽  
Impact Angle ◽  
State Variables ◽  
Flight Trajectory ◽  
Potential Significance ◽  
Guidance Law ◽  
Terminal Constraints ◽  
The Impact ◽  
Guidance Laws ◽  
Impact Angle Constraint

A new design method for trajectory shaping guidance laws with the impact angle constraint is proposed in this study. The basic idea is that the multiplier introduced to combine the equations for the terminal constraints is used to shape a flight trajectory as desired. To this end, the general form of impact angle control guidance (IACG) is first derived as a function of an arbitrary constraint-combining multiplier using the optimal control. We reveal that the constraint-combining multiplier satisfying the kinematics can be expressed as a function of state variables. From this result, the constraint-combining multiplier to achieve a desired trajectory can be obtained. Accordingly, when the desired trajectory is designed to satisfy the terminal constraints, the proposed method directly can provide a closed form of IACG laws that can achieve the desired trajectory. The potential significance of the proposed result is that various trajectory shaping IACG laws that can cope with various guidance goals can be readily determined compared to existing approaches. In this study, several examples are shown to validate the proposed method. The results also indicate that previous IACG laws belong to the subset of the proposed result. Finally, the characteristics of the proposed guidance laws are analyzed through numerical simulations.

scholarly journals The effect of heat treatment and impact angle on the erosion behavior of nickel-tungsten carbide cold spray coating using response surface methodology

2021 ◽  
Author(s):  
Marios Kazasidis ◽  
Elisa Verna ◽  
Shuo Yin ◽  
Rocco Lupoi
Keyword(s):  
Heat Treatment ◽  
Response Surface Methodology ◽  
Mass Loss ◽  
Tungsten Carbide ◽  
Response Surface ◽  
Spray Coating ◽  
Impact Angle ◽  
Control Factors ◽  
Heat Treated ◽  
The Impact

AbstractThis study elucidates the performance of cold-sprayed tungsten carbide-nickel coating against solid particle impingement erosion using alumina (corundum) particles. After the coating fabrication, part of the specimens followed two different annealing heat treatment cycles with peak temperatures of 600 °C and 800 °C. The coatings were examined in terms of microstructure in the as-sprayed (AS) and the two heat-treated conditions (HT1, HT2). Subsequently, the erosion tests were carried out using design of experiments with two control factors and two replicate measurements in each case. The effect of the heat treatment on the mass loss of the coatings was investigated at the three levels (AS, HT1, HT2), as well as the impact angle of the erodents (30°, 60°, 90°). Finally, the response surface methodology (RSM) was applied to analyze and optimize the results, building the mathematical models that relate the significant variables and their interactions to the output response (mass loss) for each coating condition. The obtained results demonstrated that erosion minimization was achieved when the coating was heat treated at 600 °C and the angle was 90°.

scholarly journals Poly(Lactic Acid)–Poly(Butylene Succinate)–Sugar Beet Pulp Composites; Part I: Mechanics of Composites with Fine and Coarse Sugar Beet Pulp Particles

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2531
Author(s):  
Rodion Kopitzky
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Sugar Beet ◽  
Cell Structure ◽  
Sugar Beet Pulp ◽  
Poly Lactic Acid ◽  
Butylene Succinate ◽  
Fracture Patterns ◽  
Beet Pulp ◽  
The Impact

Sugar beet pulp (SBP) is a residue available in large quantities from the sugar industry, and can serve as a cost-effective bio-based and biodegradable filler for fully bio-based compounds based on bio-based polyesters. The heterogeneous cell structure of sugar beet suggests that the processing of SBP can affect the properties of the composite. An “Ultra-Rotor” type air turbulence mill was used to produce SBP particles of different sizes. These particles were processed in a twin-screw extruder with poly(lactic acid) (PLA) and poly(butylene succinate) (PBS) and fillers to granules for possible marketable formulations. Different screw designs, compatibilizers and the use of glycerol as a thermoplasticization agent for SBP were also tested. The spherical, cubic, or ellipsoidal-like shaped particles of SBP are not suitable for usage as a fiber-like reinforcement. In addition, the fineness of ground SBP affects the mechanical properties because (i) a high proportion of polar surfaces leads to poor compatibility, and (ii) due to the inner structure of the particulate matter, the strength of the composite is limited to the cohesive strength of compressed sugar-cell compartments of the SBP. The compatibilization of the polymer–matrix–particle interface can be achieved by using compatibilizers of different types. Scanning electron microscopy (SEM) fracture patterns show that the compatibilization can lead to both well-bonded particles and cohesive fracture patterns in the matrix. Nevertheless, the mechanical properties are limited by the impact and elongation behavior. Therefore, the applications of SBP-based composites must be well considered.

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