Containment and Arrest of Blade Shedding in Gas Turbine Engines Using Novel Dual-Ring Design

2021 ◽  
Author(s):  
Prayers Roy ◽  
Shaker A. Meguid
Keyword(s):  
Energy Absorption ◽  
Impact Damage ◽  
Impact Resistance ◽  
High Energy ◽  
Element Analysis ◽  
Single Ring ◽  
High Energy Absorption ◽  
Interfacial Gap ◽  
The Impact ◽  
Dual Ring

Abstract In this paper, we examine the energy absorption and containment capabilities of a newly proposed dual-ring design accounting for interactions between a released blade and fully bladed fan disk using 3D finite element analysis. The components of this dual-ring design are strategically selected to ensure high energy absorption and high impact resistance, thus leading to reduced damage of the disk and increased safety. Three containment ring designs are examined: (i) conventional single-ring design composed of one of titanium, aluminum or Kevlar, (ii) a newly proposed aluminium-Kevlar dual-ring arrangement, and (iii) dual-ring arrangement with an interfacial gap between them to arrest and contain the released blade and ensure free passage of the trailing blades. The results of our numerical simulations indicate that although the single-ring design resists penetration and contains the released blade within the confines of the disk, it does not remove the released blade from the path of the trailing blades leading to severe damage to the fan disk. On the contrary, our new dual-ring design, which contains an interfacial gap, has potential to successfully arrest the released blade within the confines of the ring and out of the path of the trailing blades. This design significantly can reduce the impact damage to the fan disk and reduces kinetic energy of the released blade to near zero in less than half a rotation of the fan disk.

Impact Response of Circular Tube with Concentric Plunger

2013 ◽  
Vol 275-277 ◽  
pp. 792-798
Author(s):  
Amir Radzi Ab Ghani ◽  
Hafizi Lukman ◽  
Hafizan Hashim
Keyword(s):  
Energy Absorption ◽  
Circular Tube ◽  
High Energy ◽  
Absorption Capacity ◽  
Peak Force ◽  
Impact Response ◽  
Impact Performance ◽  
High Energy Absorption ◽  
The Impact ◽  
Initial Peak

Thin-walled tubes are generally used as impact energy absorber in various application due to their ease of fabrication and installation, high energy absorption capacity and long stroke. However, the main drawback of plain tube is the high initial peak force. A concentric plunger in the form of tapered block is proposed to overcome this shortcoming while at the same time, improving the impact performance. Static and dynamic axial crushing were performed to determine the initial peak force (IPF), crush force efficiency (CFE) and specific energy absorption (SEA) for the concentric plunger with various taper angles. It was found that the concentric plunger affected the tube impact response. Comparison with plain circular tube was carried out and it was found that the concentric plunger improved the impact response of the tube especially in term of initial peak force.

Impact Resistance of SM Joints Formed With ICA

2002 ◽  
Vol 124 (4) ◽  
pp. 374-378 ◽  
Author(s):  
C. M. Lawrence Wu ◽  
Robert K. Y. Li ◽  
N. H. Yeung
Keyword(s):  
Impact Damage ◽  
Impact Resistance ◽  
High Energy ◽  
Bending Test ◽  
Conductive Adhesives ◽  
Energy Impact ◽  
Split Hopkinson ◽  
Post Impact ◽  
Impact Bending ◽  
The Impact

Isotropic conductive adhesives (ICA) have been considered as replacement materials for lead-tin solder alloys. In this paper, the post-impact shear strength of ICA surface mount (SM) joints was obtained experimentally and compared with that of SM lead-tin joints. The dynamic impact energy was provided in the form of three-point bending on the PCB using equipment called the split Hopkinson bar. Strain rates of over 4000/s were used for the impact bending test. The action of impact bending was used to simulate the effect on the PCB and the interconnection as a result of high energy impact on an electronic equipment. Shear test was then performed to examine the change in strength of the ICA joints as a result of impact damage. It was found that the SM ICA joints failed due to impact at a strain rate just over 4000/s. Microstructural examination carried out using a scanning electron microscope revealed that the interface between the ICA and copper pad on the PCB was the weakest region of the joint.

Effect of Parameter Optimization of Contact Force Models on the Impact Dynamic Responses

1993 ◽  
Author(s):  
H. M. Lankarani ◽  
F. Wu
Keyword(s):  
Energy Absorption ◽  
Contact Force ◽  
Multibody System ◽  
High Energy ◽  
Contact Forces ◽  
Dynamic Responses ◽  
Particle Model ◽  
Force Model ◽  
High Energy Absorption ◽  
The Impact

Abstract Reducing the severity of an impact to a structure or a multibody system is a significant aspect of engineering design. This requires the knowledge of variations of the resulting contact forces and also how these contact forces can be reduced. This paper presents an optimization methodology for the selection of proper parameters in the contact/impact force models so as to minimize the maximum value of the contact force. A two-particle model of an impact between two solids is considered, and then generalized to the impact analysis between two bodies of a multibody system. The concept of effective mass is presented in order to compensate for the effect of joint forces or impulses. The system is reduced to a single degree-of-freedom mass-spring-damper vibro-impact system. A single differential equation of motion in the direction of relative indentation of local contact surfaces is derived. Different contact force models of hysteresis form including linear and nonlinear models are described. An optimization problem is then formulated and solved by using the method of modified feasible direction for constrained minimization. A numerical integrator is used at every design iteration to obtain the system dynamic response for a given set of design variables. The objective function is to minimize the peak acceleration of the system equivalent mass resulting from the contact force. Comparison of the system with optimal parameters and non-optimal one shows that the peak contact force is greatly reduced for the optimal one. Since these parameters reflect the material properties (stiffness and damping) of the impacting bodies or surfaces, suitable materials may then be selected based upon the information provided by this optimization procedure. It is observed that the materials, which have good crashworthiness properties should posses capability of dissipating impact energy both in the forms of permanent indentation and internal damping friction. Based upon the analysis of the impact responses, mechanism of energy dissipation, and the typical force-indentation diagram for the high energy absorption materials obtained from experiments, a new contact force model is proposed which could precisely describe the impact response of high energy-absorption materials.

Impact Resistance of SM Joints Formed With ICA

2003 ◽  
Vol 125 (1) ◽  
pp. 93-97 ◽  
Author(s):  
C. M. Lawrence Wu ◽  
Robert K. Y. Li ◽  
N. H. Yeung
Keyword(s):  
Impact Damage ◽  
Impact Resistance ◽  
High Energy ◽  
Bending Test ◽  
Conductive Adhesives ◽  
Energy Impact ◽  
Split Hopkinson ◽  
Post Impact ◽  
Impact Bending ◽  
The Impact

Isotropic conductive adhesives (ICA) have been considered as replacement materials for lead-tin solder alloys. In this paper, the post-impact shear strength of ICA surface mount (SM) joints was obtained experimentally and compared with that of SM lead-tin joints. The dynamic impact energy was provided in the form of three-point bending on the PCB using equipment called the split Hopkinson bar. Strain rates of over 4000/s were used for the impact bending test. The action of impact bending was used to simulate the effect on the PCB and the interconnection as a result of high energy impact on an electronic equipment. Shear test was then performed to examine the change in strength of the ICA joints as a result of impact damage. It was found that the SM ICA joints failed due to impact at a strain rate just over 4000/s. Microstructural examination carried out using a scanning electron microscope revealed that the interface between the ICA and copper pad on the PCB was the weakest region of the joint.

Investigation of Hydrophobic Nanoporous Particle Liquids for Impact Protection

2016 ◽  
Author(s):  
Yi Hsu ◽  
Yingtao Liu
Keyword(s):  
Energy Absorption ◽  
Impact Damage ◽  
Hydraulic Cylinder ◽  
High Energy ◽  
Absorption Efficiency ◽  
Nano Materials ◽  
Energy Absorption Efficiency ◽  
Trap Liquid ◽  
Impact Protection ◽  
High Energy Absorption

Recently, the development of hydrophobic nanoporous liquids has drawn increased attention, especially for the applications of energy absorption and impact protection. Although significant amount of research has been conducted to synthesis and characterize materials to protect structures from impact damage, the tradition methods needed to convert kinetic energy to other forms, such as heat and cell bulking, during impact protection. Due to their high energy absorption efficiency, hydrophobic nanoporous particle liquids are one of the most attractive impact mitigation materials. When impacted, such particles directly trap liquid molecules inside the non-wetting surface of nanopores in the particles. The captured impact energy is simply stored temporarily and isolated from the original energy transmission path. In this paper we investigate the energy absorption efficiency of multiple nanoporous particles and liquids. Inorganic nanoporous silica nanoparticles are investigated as the hydrophobic materials. Nanoporous particle liquids are prepared by dispersing the nano-materials in deionized water. The effects of small molecular promoters, such as methanol and ethanol, on energy absorption efficiency, are studied in this paper. The energy absorption efficiency of these liquids is experimentally characterized using an Instron mechanical testing frame and in-house develop stainless steel hydraulic cylinder system under quasi-static load conditions.

Novel Design of Impact Attenuator for an 'Eco Challenge' Car

2012 ◽  
Vol 165 ◽  
pp. 237-241 ◽  
Author(s):  
Amir Radzi Ab Ghani ◽  
Ramlan Kasiran ◽  
Mohd Shahriman Adenan ◽  
Mohd Haniff Mat ◽  
Rizal Effendy Mohd Nasir ◽  
...  
Keyword(s):  
Energy Absorption ◽  
Impact Energy ◽  
High Energy ◽  
Absorption Capacity ◽  
Flat Plates ◽  
Final Design ◽  
High Energy Absorption ◽  
Energy Absorbing ◽  
Long Stroke ◽  
The Impact

Thin-walled metallic tubular structures are generally used as impact energy absorber in automotive structures due to their ease of fabrication and installation, high energy absorption capacity and long stroke. However, unlike a normal passenger car where the impact energy can be distributed throughout the whole structure, the impact energy absorbing system of an Eco-Challenge car is confined within a limited space on the front bulkhead. The challenge is to develop an impact attenuator system that can effectively absorb the impact energy within the given space and fulfil the specified rate of deceleration. This new design utilized the standard Aluminium 6063 circular tubes, cut and welded into specific configurations i.e. stacked toroidal tubes with central axial tube sandwiched between two flat plates. Two configurations were investigated; circular and square toroids. Explicit non-linear FEA software was used to determine the impact response i.e. energy absorption, impact force and rate of deceleration. Both configurations showed promising results but the configuration that can be readily fabricated was chosen as the final design.

scholarly journals Evaluation of Energy Absorption Capabilities of Polyethylene Foam under Impact Deformation

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3613
Author(s):  
Baohui Yang ◽  
Yangjie Zuo ◽  
Zhengping Chang
Keyword(s):  
Energy Absorption ◽  
Failure Modes ◽  
High Strain ◽  
Early Stage ◽  
High Energy ◽  
Test Method ◽  
Test Theory ◽  
Strain Rates ◽  
Impact Properties ◽  
The Impact

Foams are widely used in protective applications requiring high energy absorption under impact, and evaluating impact properties of foams is vital. Therefore, a novel test method based on a shock tube was developed to investigate the impact properties of closed-cell polyethylene (PE) foams at strain rates over 6000 s−1, and the test theory is presented. Based on the test method, the failure progress and final failure modes of PE foams are discussed. Moreover, energy absorption capabilities of PE foams were assessed under both quasi-static and high strain rate loading conditions. The results showed that the foam exhibited a nonuniform deformation along the specimen length under high strain rates. The energy absorption rate of PE foam increased with the increasing of strain rates. The specimen energy absorption varied linearly in the early stage and then increased rapidly, corresponding to a uniform compression process. However, in the shock wave deformation process, the energy absorption capacity of the foam maintained a good stability and exhibited the best energy absorption state when the speed was higher than 26 m/s. This stable energy absorption state disappeared until the speed was lower than 1.3 m/s. The loading speed exhibited an obvious influence on energy density.

IMPACT RESISTANCE PROPERTIES OF KEVLAR/GLASS FIBER HYBRID COMPOSITE LAMINATES

2015 ◽  
Vol 76 (3) ◽  
Author(s):  
Norazean Shaari ◽  
Aidah Jumahat ◽  
M. Khafiz M. Razif
Keyword(s):  
Glass Fiber ◽  
Hybrid Composite ◽  
Composite Laminates ◽  
Impact Damage ◽  
Impact Resistance ◽  
Impact Behavior ◽  
Slight Reduction ◽  
Depth Of Penetration ◽  
Damage Degree ◽  
The Impact

In this paper, the impact behavior of Kevlar/glass fiber hybrid composite laminates was investigated by performing the drop weight impact test (ASTM D7136). Composite laminates were fabricated using vacuum bagging process with an epoxy matrix reinforced with twill Kevlar woven fiber and plain glass woven fiber. Four different types of composite laminates with different ratios of Kevlar to glass fiber (0:100, 20:80, 50:50 and 100:0) were manufactured. The effect of Kevlar/glass fiber content on the impact damage behavior was studied at 43J nominal impact energy. Results indicated that hybridization of Kevlar fiber to glass fiber improved the load carrying capability, energy absorbed and damage degree of composite laminates with a slight reduction in deflection. These results were further supported through the damage pattern analysis, depth of penetration and X-ray evaluation tests. Based on literature work, studies that have been done to investigate the impact behaviour of woven Kevlar/glass fiber hybrid composite laminates are very limited. Therefore, this research concentrates on the effect of Kevlar on the impact resistance properties of woven glass fibre reinforced polymer composites.

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