scholarly journals Crash Energy Management Crush Zone Designs: Features, Functions, and Forms

2007 ◽  
Author(s):  
Michelle Priante ◽  
Eloy Martinez
Keyword(s):  
Energy Management ◽  
Large Scale ◽  
Functional Performance ◽  
Equal Mass ◽  
Design Strategies ◽  
Lateral Buckling ◽  
Passenger Train ◽  
Alternative Design ◽  
Energy Absorbers ◽  
Crush Zone

On March 23, 2006, a full-scale test was conducted on a passenger train retrofitted with newly developed cab and coach car crush zone designs. This test was conducted as part of a larger testing program to establish the degree of enhanced performance of alternative design strategies for passenger rail crashworthiness. The alternative design strategy is referred to as Crash Energy Management (CEM) where the collision energy is absorbed in defined unoccupied locations throughout the train in a controlled progressive manner. By controlling the deformations at critical locations, the CEM train is able to protect against two very dangerous modes of deformation: override and large scale lateral buckling. The CEM train impacted a standing locomotive-led train of equal mass at 30.8 mph on tangent track. The interactions at the colliding interface and between coupled interfaces performed as designed. Crush was pushed back to subsequent crush zones, and the moving passenger train remained in-line and upright on the tracks with minimal vertical and lateral motions. This paper evaluates the functional performance of the crush zone components during the CEM test. The paper discusses three areas of the CEM consist: the leading cab car end, which interacts with a standing locomotive; the coupled interfaces, which connect the CEM non-cab end; and the trailing cab car end, which interacts with the attached trailing locomotive. The paper includes a description of the crush zone features and performance. The pushback coupler must absorb energy in a controlled progressive manner and prevent lateral buckling by allowing the ends of the cars to come together. The deformable anti-climbers are required to resolve non-longitudinal loads into planar loads through the integrated end frame while minimizing the potential for override. The energy absorbers must absorb energy in a controlled progressive manner. The engineer’s space must be preserved so that the engineer can ride out the event. The passenger space must be preserved so that the passengers can ride out the event. The prototype CEM design presented in this paper met all the functional design requirements. This paper describes how the crush zones perform at three different interfaces. Areas for potential improvements include the design of the primary energy absorbers, the placement of the engineer’s compartment, and the interaction between the last coach car and the trailing locomotive.

scholarly journals Train-to-Train Impact Test of Crash Energy Management Passenger Rail Equipment: Structural Results

2006 ◽  
Author(s):  
David Tyrell ◽  
Karina Jacobsen ◽  
Eloy Martinez ◽  
A. Benjamin Perlman
Keyword(s):  
Energy Management ◽  
Large Scale ◽  
Equal Mass ◽  
Full Scale ◽  
Full Scale Test ◽  
Design Strategies ◽  
Alternative Design ◽  
Passenger Rail ◽  
Scale Test ◽  
Crush Zone

On March 23, 2006, a full-scale test was conducted on a passenger rail train retrofitted with newly developed cab end and non-cab end crush zone designs. This test was conducted as part of a larger testing program to establish the degree of enhanced performance of alternative design strategies for passenger rail crashworthiness. The alternative design strategy is referred to as crash energy management (CEM), where the collision energy is absorbed in defined unoccupied locations throughout the train in a controlled progressive manner. By controlling the deformations at critical locations the CEM train is able to protect against two dangerous modes of deformation: override and large-scale lateral buckling. The CEM train impacted a standing locomotive-led train of equal mass at 31 mph on tangent track. The interactions at the colliding in Interface and between coupled interfaces performed as expected. Crush was pushed back to subsequent crush zones and the moving passenger train remained in-line and upright on the tracks with minimal vertical and lateral motions. The added complexity associated with this test over previous full-scale tests of the CEM design was the need to control the interactions at the colliding interface. between the two very different engaging geometries. The cab end crush zone performed as intended because the locomotive coupler pushed underneath the cab car buffer beam, and the deformable anti-climber engaged the uneven geometry of the locomotive anti-climber and short hood. Space was preserved for the operator as the cab end crush zone collapsed. The coupled interfaces performed as predicted by the analysis and previous testing. The conventional interlocking anti-climbers engaged after the pushback couplers triggered and absorbed the prescribed amount of energy. Load was transferred through the integrated end frame, and progressive controlled collapsed was contained to the energy absorbers at the roof and floor level. The results of this full-scale test have clearly demonstrated the significant enhancement in safety for passengers and crew members involved in a push mode collision with a standing locomotive train.

scholarly journals Development of Crash Energy Management Designs for Existing Passenger Rail Vehicles

2004 ◽  
Author(s):  
Eloy Martinez ◽  
David Tyrell ◽  
Benjamin Perlman
Keyword(s):  
Energy Management ◽  
Full Scale ◽  
Lateral Buckling ◽  
Passenger Rail ◽  
Rail Vehicles ◽  
Used Car ◽  
Baseline Levels ◽  
Full Scale Tests ◽  
Prototype Design ◽  
Crush Zone

As part of the passenger equipment crashworthiness research, sponsored by the Federal Railroad Administration and supported by the Volpe Center, passenger coach and cab cars have been tested in inline collision conditions. The purpose of these tests was to establish baseline levels of crashworthiness performance for the conventional equipment and demonstrate the minimum achievable levels of enhancement using performance based alternatives. The alternative strategy pursued is the application of the crash energy management design philosophy. The goal is to provide a survivable volume where no intrusion occurs so that passengers can safely ride out the collision or derailment. In addition, lateral buckling and override modes of deformation are prevented from occurring. This behavior is contrasted with that observed from both full scale tests recently conducted and historical accidents where both lateral buckling and/or override occurs for conventionally designed equipment. A prototype crash energy management coach car design has been developed and successfully tested in two full-scale tests. The design showed significant improvements over the conventional equipment similarly tested. The prototype design had to meet several key requirements including: it had to fit within the same operational volume of a conventional car, it had to be retrofitted onto a previously used car, and it had to be able to absorb a prescribed amount of energy within a maximum allowable crush distance. To achieve the last requirement, the shape of the force crush characteristic had to have tiered force plateaus over prescribed crush distances to allow for crush to be passed back from one crush zone to another. The distribution of crush along the consist length allows for significantly higher controlled energy absorption which results in higher safe closing speeds.

scholarly journals Performance Efficiency of a Crash Energy Management System

2007 ◽  
Author(s):  
Michael Carolan ◽  
David Tyrell ◽  
A. Benjamin Perlman
Keyword(s):  
Energy Management ◽  
Primary Energy ◽  
Baseline Characteristic ◽  
Lumped Mass ◽  
Mass Model ◽  
Passenger Train ◽  
Passenger Rail ◽  
Draft Gear ◽  
Energy Absorbers ◽  
The Individual

Previous work has led to the development of a crash energy management (CEM) system designed to distribute crush throughout unoccupied areas of a passenger train in a collision event. This CEM system is comprised of crush zones at the front and rear ends of passenger railcars. With a consist made up of CEM-equipped cars, the structural crush due to a collision can be distributed along the length of the train, crushing only unoccupied areas and improving the train’s crashworthy speed as compared with a conventional train in a similar collision. This paper examines the effectiveness of one particular CEM system design for passenger rail cars. The operating parameters of the individual components of the CEM system are varied, and this paper analyzes the effects of these variations on the behavior of the consist during a collision. The intention is to determine what modifications to the components, if any, could improve the crashworthiness of passenger railcars beyond the baseline CEM design without introducing new hazards to passengers. A one-dimensional, lumped-mass model of a passenger train impacting a heavy freight train was used in this investigation. Using this model of a collision, the force-crush behavior for each end of each car in the impacting consist was varied. The same force-crush characteristic was applied to each car end on the passenger train. The four components of the CEM system investigated were the draft gear, pushback coupler, primary energy absorbers, and occupied volume of the train car. The paper presents selected parameters of particular interest, such as the strength ratio of the primary energy absorber to the pushback coupler and the average strength of the occupied volume. The objective of this work was to ascertain the sensitivities of the various parameters on the crashworthy speed and to help optimize the force-crush characteristic. This investigation determined that modifications could be made to the baseline characteristic to improve the train’s crashworthy speed without creating new hazards to occupants.

Large Scale predictive analytics for real-time energy management

2013 ◽  
Author(s):  
Natasha Balac ◽  
Tamara Sipes ◽  
Nicole Wolter ◽  
Kenneth Nunes ◽  
Bob Sinkovits ◽  
...  
Keyword(s):  
Real Time ◽  
Energy Management ◽  
Large Scale ◽  
Predictive Analytics

scholarly journals Energy management in sensor networks

2012 ◽  
Vol 370 (1958) ◽  
pp. 52-67 ◽  
Author(s):  
John A. Stankovic ◽  
Tian He
Keyword(s):  
Energy Consumption ◽  
Sensor Networks ◽  
Energy Management ◽  
Large Scale ◽  
Energy Savings ◽  
Time Synchronization ◽  
Media Access Control ◽  
Media Access ◽  
Energy Aware ◽  
Holistic View

This paper presents a holistic view of energy management in sensor networks. We first discuss hardware designs that support the life cycle of energy, namely: (i) energy harvesting, (ii) energy storage and (iii) energy consumption and control. Then, we discuss individual software designs that manage energy consumption in sensor networks. These energy-aware designs include media access control, routing, localization and time-synchronization. At the end of this paper, we present a case study of the VigilNet system to explain how to integrate various types of energy management techniques to achieve collaborative energy savings in a large-scale deployed military surveillance system.

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