Optimal design of pre-triggering airbag system for occupant protection performance during frontal crashes

2018 ◽  
Vol 233 (11) ◽  
pp. 2850-2862 ◽  
Author(s):  
Zhi Xiao ◽  
Li Wang ◽  
Fuhao Mo ◽  
Siqi Zhao ◽  
Cuina Liu
Keyword(s):  
Mass Flow ◽  
Rapid Development ◽  
Physical Parameters ◽  
Restraint System ◽  
Frontal Impacts ◽  
Chest Injuries ◽  
Car Crash ◽  
Analysis Center ◽  
Frontal Crashes ◽  
Injury Protection

With the rapid development of car crash sensing and identification technology, the application of pre-triggering airbag system is becoming an important option to improve vehicle safety. Thus, the present study aims to investigate the injury protection ability of pre-triggering airbag system and optimize its performance in frontal crashes regarding the key physical parameters. A driver restraint system model established and validated by National Crash Analysis Center was employed and validated for studying the injury protection ability of pre-triggering airbag system. Then, the influences of airbag triggering time, airbag volume scaling factor, inflator mass flow, and exhaust orifice size of pre-triggering airbag system on driver’s head and chest injuries were analyzed. Finally, the weighted injury criterion was selected as the evaluation index to optimize the pre-triggering airbag system. The results show the pre-triggering airbag should be designed with a larger airbag volume and inflator mass flow rate and smaller exhaust orifice. The optimized restraint system design presents a reduction of weighted injury criterion values in 100% and 40% overlapped frontal impacts reaching 25.63% and 42.23%, respectively.

Finite Element Investigation of Out-of-Position Failure Modes for the Knee-Thigh-Hip of a 50th Percentile Male During a Frontal Car Crash

2009 ◽  
Author(s):  
Chiara Silvestri ◽  
Malcolm H. Ray
Keyword(s):  
Finite Element ◽  
Failure Modes ◽  
Element Model ◽  
The Body ◽  
Lower Extremity Injuries ◽  
Frontal Impacts ◽  
Car Crash ◽  
Life Threatening ◽  
Frontal Crashes ◽  
Extremity Injuries

The introduction of air bags has reduced injuries to the upper region of the body for occupants of vehicles in frontal crashes, such as head and thorax. Airbags have not, however, improved the safety of occupants with respect to injuries to the lower extremities. Though lower extremity injuries are usually not life threatening, they can have long lasting physical and psychosocial consequences. A validated Knee-Thigh-Hip (KTH) finite element model of a 50th percentile male was used to investigate injury mechanisms during frontal car crashes with the occupant in different positions. Simulations of frontal impacts were performed with the Knee-Thigh-Hip joints at different angles of thigh flexion, adduction and abduction. Results show that the failure mechanism can significantly depend on the occupant position prior to impact. Failure mechanisms in the simulations were compared to results found in literature to ensure the model provides a useful tool for predicting fractures in the lower limb resulting from out-of-position frontal vehicle crashes.

scholarly journals Factors associated with chest injuries to front seat occupants in frontal impacts

2019 ◽  
Vol 20 (sup2) ◽  
pp. S37-S42 ◽  
Author(s):  
Karthikeyan Ekambaram ◽  
Richard Frampton ◽  
James Lenard
Keyword(s):  
Front Seat ◽  
Factors Associated ◽  
Frontal Impacts ◽  
Chest Injuries

scholarly journals Thermal Characteristics Analysis on Multi- Heat Pipe Induced Heat Exchanger

2019 ◽  
Vol 9 (2S2) ◽  
pp. 143-147 ◽  
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Heat Pipe ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Cold Water ◽  
Hot Water ◽  
Working Fluid ◽  
Physical Parameters

In this investigation of multi heat pipe induced in heat exchanger shows the developments in heat transfer is to improve the efficiency of heat exchangers. Water is used as a heat transfer fluid and acetone is used as a working fluid. Rotameter is set to measure the flow rate of cold water and hot water. To maintain the parameter as experimental setup. Then set the mass flow rate of hot water as 40 LPH, 60LPH, 80 LPH, 100LPH, 120 LPH and mass flow rate of cold water as 20 LPH, 30 LPH, 40 LPH, 50 LPH, and 60 LPH. Then 40 C, 45 ºC, 50 ºC, 55 C, 60 ºC are the temperatures of hot water at inlet are maintained. To find some various physical parameters of Qc , hc , Re ,, Pr , Rth. The maximum effectiveness of the investigation obtained from condition of Thi 60 C, Tci 32 C and 100 LPH mhi, 60 LPH mci the maximum effectiveness attained as 57.25. Then the mhi as 100 LPH, mci as 60 LPH and Thi at 40 C as 37.6%. It shows the effectiveness get increased about 34.3 to the maximum conditions.

Investigation of Heavy Truck Restraint System Effectiveness Through Finite Element Computer Simulations in Frontal Crashes

2016 ◽  
Author(s):  
Nathan Schulz ◽  
Chiara Silvestri Dobrovolny ◽  
Abhinav Mohanakrishnan
Keyword(s):  
Finite Element ◽  
Injury Severity ◽  
Seat Belt ◽  
Restraint System ◽  
Rigid Barrier ◽  
Heavy Trucks ◽  
Ring Location ◽  
Heavy Truck ◽  
Frontal Crashes ◽  
Occupant Kinematics

Computer finite element simulations play an important role in reducing the cost and time taken for prediction of a crash scenario. While interior crash protection has received adequate attention for automobiles, very little is known for commercial vehicle such as heavy trucks. The understanding of injury types for heavy trucks occupants in relation to different crash scenarios would help mitigation of the injury severity. Finite element computer models of the heavy truck cabin structure, interior cabin components, anthropomorphic test device (ATD) (also called dummy) and passive restraint systems were developed and assembled to simulate head-on crash of a heavy truck into a rigid barrier. The researchers developed a computer simulation parametric evaluation with respect to specific seat belt restraint system parameters for a speed impact of 56.3 km/h (35 mph). Restraint parameter variations within this research study are seat belt load limiting characteristics, inclusion of seat belt pretensioner, and variation of seat belt D-ring location. Additionally an airbag was included to investigate another restraint system. For each simulated impact characteristic and restraint system variation, the occupant kinematics were observed and occupant risks were assessed. Within the approximations and assumptions included in this study, the results presented in this paper should be considered as preliminary guidance on the effectiveness of the use of seat belt as occupant injury mitigation system.

scholarly journals Comparison of Dry Versus Wet Milling to Improve Bioethanol or Methane Recovery from Solid Anaerobic Digestate

2019 ◽  
Vol 6 (3) ◽  
pp. 80
Author(s):  
Monlau ◽  
Sambusiti ◽  
barakat
Keyword(s):  
Agricultural Sector ◽  
Waste Treatment ◽  
Ethanol Yield ◽  
Rapid Development ◽  
Crystallinity Index ◽  
Physical Parameters ◽  
Wet Milling ◽  
Methane Recovery ◽  
Physicochemical Composition ◽  
Methane Potential

Biogas plants for waste treatment valorization are presently experiencing rapid development, especially in the agricultural sector, where large amounts of digestate are being generated. In this study, we investigated the effect of vibro-ball milling (VBM) for 5 and 30 min at a frequency of 20 s−1) on the physicochemical composition and enzymatic hydrolysis (30 U g−1 total solids (TS) of cellulase and endo-1,4-xylanase from Trichoderma longibrachiatum) of dry and wet solid digestates from an agricultural biogas plant. We found that VBM of dry solid digestate improved the physical parameters as both the particle size and the crystallinity index (from 27% to 75%) were reduced. By contrast, VBM of wet solid digestate had a minimal effect on the physicochemical parameters. The best results in terms of cellulose and hemicelluloses hydrolysis were noted for 30 min of VBM of dry solid digestate, with hydrolysis yields of 64% and 85% for hemicelluloses and cellulose, respectively. For the condition of 30 min of VBM, bioethanol and methane production on the dry solid separated digestate was investigated. Bioethanol fermentation by simultaneous saccharification and fermentation resulted in an ethanol yield of 98 geth kg−1 TS (corresponding to 90% of the theoretical value) versus 19 geth kg−1 TS for raw solid digestate. Finally, in terms of methane potential, VBM for 30 min lead to an increase of the methane potential of 31% compared to untreated solid digestate.

scholarly journals (A214) Road War: A 200-Vehicle Crash, Special Report

2011 ◽  
Vol 26 (S1) ◽  
pp. s59-s59
Author(s):  
G.E.A. Khalifa
Keyword(s):  
Abu Dhabi ◽  
Special Report ◽  
Social Barriers ◽  
Golden Hour ◽  
Traffic Police ◽  
Chest Injuries ◽  
Car Crash ◽  
Extremity Trauma ◽  
The World ◽  
Hospital Response

The last thing the world needs is another war.1 Everyday about 3000 people die and 30,000 people are seriously injured on the world's roads.2 Furthermore, for people who survive the crash, additional suffering and frustration occur because of administrative, legal, and social barriers.3 Since transport to hospital usually takes 30–45 minutes, the ‘golden hour’ in which 48% of deaths occur is spent mainly in the prehospital environment.4 On March 11, 2008 at 7:30 AM a very foggy morning, a major car crash occurred on the high way from Abu Dhabi to Dubai. Initial scene response was conducted by Abu Dhabi traffic police Abu Dhabi Police Ambulance and Rescue Sections helped by Dubai. Casualities were transported to 2 hospitals in Abu Dhabi; Al Mafraq and Al Rahba. The Authors describes Al Rahba hospital response that received 159 causalities (almost half of the causalities).ResultsThree victims died immediately on scene. Most of the causalities were triaged and re triaged as Priority 3 (green), suffered from extremity trauma, were treated and discharged. Twenty patients were triaged as Priority 2 (yellow) and were admitted to the hospital, Three patients were priority one (red) were admitted to the ICU, one of them died 10 days later due to severe head and chest injuries.

scholarly journals Mathematical Modeling and Parameters Estimation of Car Crash Using Eigensystem Realization Algorithm and Curve-Fitting Approaches

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Bernard B. Munyazikwiye ◽  
Hamid Reza Karimi ◽  
Kjell Gunnar Robbersmyr
Keyword(s):  
Curve Fitting ◽  
Parameters Estimation ◽  
Crash Test ◽  
Physical Parameters ◽  
Eigensystem Realization Algorithm ◽  
The Real ◽  
Car Crash ◽  
Acceleration Data ◽  
Mass Damper ◽  
Vehicle Chassis

An eigensystem realization algorithm (ERA) approach for estimating the structural system matrices is proposed in this paper using the measurements of acceleration data available from the real crash test. A mathematical model that represents the real vehicle frontal crash scenario is presented. The model’s structure is a double-spring-mass-damper system, whereby the front mass represents the vehicle-chassis and the rear mass represents the passenger compartment. The physical parameters of the model are estimated using curve-fitting approach, and the estimated state system matrices are estimated by using the ERA approach. The model is validated by comparing the results from the model with those from the real crash test.

Meshfree Method in Geophysical Electromagnetic Prospecting: The 2D Magnetotelluric Example

2017 ◽  
Vol 15 (02) ◽  
pp. 1750084 ◽  
Author(s):  
Yanju Ji ◽  
Tingzhe Huang ◽  
Wanyu Huang ◽  
Liangliang Rong
Keyword(s):  
Numerical Simulation ◽  
Large Scale ◽  
High Efficiency ◽  
Interpolation Method ◽  
Rapid Development ◽  
Linear Equations ◽  
Meshfree Method ◽  
Physical Parameters ◽  
Traditional Methods ◽  
Calculation Results

As an important supplement and development of traditional methods, the meshfree method has received a great deal of attention in the field of engineering calculation, and has been successfully used to solve many problems which traditional methods have difficulty in solving. However, the application of meshfree method is relatively less in the area of geophysics. In this paper, we apply the meshfree method to the numerical simulation of geophysical electromagnetic prospecting, taking the 2D magnetotelluric as an example and deduce the corresponding meshfree radial point interpolation method (RPIM) equivalent linear equations in detail. The high-efficiency and accurate solutions of large-scale sparse linear equations are solved by the quasi-minimal residual method based on Krylov subspace. The optimal values of the shape parameters are given by numerical experiments. The correctness of the meshfree method is verified by a layered model. The root mean square error of the calculation results is no more than 0.35%, its accuracy is superior to the finite element method. We also compare the meshfree solution with FEM solution by calculating an inclined vein body model, and the calculation results are in good agreement. A continuously changing fault model and undulating terrain model which traditional methods have difficulty in simulating are respectively calculated, the sectional profiles of the apparent resistivity accurately reflect the trend of the anomalies. The meshfree method does not require the complicated mesh generation, and the physical parameters are loaded at a series of points, thus it is especially suitable for the calculation of the complex geological models. With the rapid development of computational science, the meshfree techniques will certainly become a new robust numerical simulation method in geophysical electromagnetic prospecting.

Restraint System Optimization for Dual Test Configurations of Frontal Crashes

2004 ◽  
Author(s):  
Yoshiko Kawabe ◽  
Tomokazu Kondo ◽  
Daisuke Masuda ◽  
Toru Mogi ◽  
Kazuhiro Obayashi ◽  
...  
Keyword(s):  
System Optimization ◽  
Restraint System ◽  
Frontal Crashes
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