Design and laboratory verification of a physical model of sloping capillary barrier

2004 ◽  
Vol 41 (5) ◽  
pp. 814-830 ◽  
Author(s):  
Denny Tami ◽  
Harianto Rahardjo ◽  
Eng-Choon Leong ◽  
Delwyn G Fredlund
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Numerical Analysis ◽  
Physical Model ◽  
Water Pressure ◽  
Experimental Studies ◽  
Silty Sand ◽  
Capillary Barrier ◽  
Simulation Results ◽  
Barrier Model

A physical model was designed and constructed to study the mechanisms associated with capillary barriers for slope stabilization purposes. Prior to construction of the model, various numerical analyses were conducted to determine the optimum dimensions and appropriate soil types for the materials of the capillary barrier model. This paper is divided into three sections: the first two sections are related to the design of the model and are to obtain the optimum dimensions of the model and to investigate the range of soil properties that are most suitable for experimental studies in the laboratory; and the last section is laboratory verification of the numerical analysis where the numerical simulation results are compared with the experimental data. Based on the numerical simulation results, the physical capillary barrier model was constructed using two different combinations of soils, namely silty sand over gravelly sand and fine sand over gravelly sand. From the comparison of the numerical results and experimental data, it was found that the numerical analysis was able to simulate the experiment on the physical capillary barrier model reasonably well.Key words: physical capillary barrier model, unsaturated water flow, numerical simulation, pore-water pressure, volumetric water content, slope stability, infiltration.

Impact Simulation of a Crashworthy Composite Fuselage Section with Energy-Absorbing Floor

2014 ◽  
Vol 529 ◽  
pp. 102-107
Author(s):  
Hai Bo Luo ◽  
Ying Yan ◽  
Xiang Ji Meng ◽  
Tao Tao Zhang ◽  
Zu Dian Liang
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Dynamic Response ◽  
Relative Error ◽  
High Strength ◽  
Computer Code ◽  
Impact Simulation ◽  
Average Acceleration ◽  
Simulation Results ◽  
Energy Absorbing

A 7.8m/s vertical drop simulate of a full composite fuselage section was conducted with energy-absorbing floor to evaluate the crashworthiness features of the fuselage section and to predict its dynamic response to dummies in future. The 1.52m diameter fuselage section consists of a high strength upper fuselage frame, one stiff structural floor and an energy-absorbing subfloor constructed of Rohacell foam blocks. The experimental data from literature [6] were analyzed and correlated with predictions from an impact simulation developed using the nonlinear explicit transient dynamic computer code MSC.Dytran. The simulated average acceleration did not exceed 13g, by contrast with experimental results, whose relative error is less than 11%. The numerical simulation results agree with experiments well.

scholarly journals Mechatronic Device for Locomotor Training

2016 ◽  
Vol 10 (4) ◽  
pp. 310-315 ◽  
Author(s):  
Sławomir Duda ◽  
Damian Gąsiorek ◽  
Grzegorz Gembalczyk ◽  
Sławomir Kciuk ◽  
Arkadiusz Mężyk
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Measurement Data ◽  
Healthy Person ◽  
Control Algorithms ◽  
Design Team ◽  
Locomotor Training ◽  
Interdisciplinary Design ◽  
Machine Control ◽  
Simulation Results

Abstract This paper presents a novel mechatronic device to support a gait reeducation process. The conceptual works were done by the interdisciplinary design team. This collaboration allowed to perform a device that would connect the current findings in the fields of biomechanics and mechatronics. In the first part of the article shown a construction of the device which is based on the structure of an overhead travelling crane. The rest of the article contains the issues related to machine control system. In the prototype, the control of drive system is conducted by means of two RT-DAC4/PCI real time cards connected with a signal conditioning interface. Authors present the developed control algorithms and optimization process of the controller settings values. The summary contains a comparison of some numerical simulation results and experimental data from the sensors mounted on the device. The measurement data were obtained during the gait of a healthy person.

Study on Numerical Simulation of Fire and Evacuation for a Supermarket

2015 ◽  
Vol 744-746 ◽  
pp. 1736-1740 ◽  
Author(s):  
Si Hui Dong ◽  
Min Li ◽  
Yu Han Lin
Keyword(s):  
Numerical Simulation ◽  
Physical Model ◽  
Development Process ◽  
Fire Danger ◽  
Actual Situation ◽  
Study Results ◽  
Simulation Results ◽  
Fire Scene ◽  
Safety Evacuation

3D physical model of a supermarket was constructed with Pyrosim software, and the fire scene was set according to the actual situation. The fire development process and personnel evacuation process were simulated with FDS. The fire danger time of the fire scene was analyzed according to the smoke temperature and visibility of different time. The personnel evacuation process to the supermarket was simulated with the evacuation software Evac, and the required safety egress time was calculated. By comparing the fire danger time and the required safety egress time, the conclusion was drawn that the supermarket can not meet the requirement for safety evacuation. After changing the conditions for safety evacuation, the required safety egress time was simulated again. And the simulation results showed that the changed evaluation conditions can meet the requirement for safety evacuation. The study results provide a basis to improve the safety evacuation conditions of the supermarket.

scholarly journals Wear Processes in a Mechanical Friction Clutch: Theoretical, Numerical, and Experimental Studies

2015 ◽  
Vol 2015 ◽  
pp. 1-28 ◽  
Author(s):  
Dariusz Grzelczyk ◽  
Jan Awrejcewicz
Keyword(s):  
Mathematical Modeling ◽  
Experimental Data ◽  
Numerical Analysis ◽  
Numerical Simulations ◽  
Experimental Studies ◽  
Friction Torque ◽  
Wear Properties ◽  
Wear Model ◽  
Differential Model ◽  
Friction Clutch

Mathematical modeling, theoretical/numerical analysis, and experimental verification of wear processes occurring on the contact surface of friction linings of a mechanical friction clutch are studied. In contrast to many earlier papers we take into consideration wear properties and flexibility of friction materials being in friction contact. During mathematical modeling and numerical simulations we consider a general nonlinear differential model of wear (differential wear model) and a model of wear in the integral form (integral wear model). Equations governing contact pressure and wear distributions of individual friction linings, decrease of distance between clutch shields, and friction torque transmitted by the clutch are derived and compared with experimental data. Both analytical and numerical analyses are carried out with the qualitative and quantitative theories of differential and integral equations, including the Laplace transform approach to ODEs. We show that theoretical results and numerical simulations agree with the experimental data. Finally, a numerical analysis of the proposed mathematical models was carried out in a wider range of parameters of the considered system.

scholarly journals Physical Model Test for Soft Soil With or Without Prefabricated Vertical Drain with Loading

2018 ◽  
Vol 4 (8) ◽  
pp. 1809
Author(s):  
Dao Huu Do ◽  
Nguyen Thi Phuong Khue ◽  
Phan Khac Hai
Keyword(s):  
Numerical Simulation ◽  
Physical Model ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
Soft Soil ◽  
Physical Model Test ◽  
Soil Parameters ◽  
Vertical Drain ◽  
Prefabricated Vertical Drain ◽  
Before And After

The paper builds a physical model of testing in the laboratory with the parametric tempered glass box 0.5  0.5 1.2 m (length  width  depth) containing saturated clay to study the settlement and consolidation when loading increased gradually over time. The research covers herein to present the monitoring of settlement and pore water pressure, settlement calculation, numerical simulation using PLAXIS software V8.2 based on the results of soil physical and mechanical tests before and after loading in case of having or not prefabricated vertical drain (PVD). In case of no PVD, the calculation and numerical simulation using the soil parameters before loading have the differential settlement from the monitoring data, approximately 3.86 mm (10.45%), 0.41 mm (1.11%) respectively. Meanwhile, the deviation in the case using data after loading is about 2.29 mm (6.20%), 0.21 mm (0.56%) respectively. In case of PVD, the calculation and numerical simulation with the testing result of before loading deviation from the settlement monitoring by subsidence meter is 2.91 mm (7.88%), 44.42 mm (120.28%), calculation and simulation with the testing result of after loading deviation is 0.80 mm (2.17%), 1.26 mm (3.41%). In the case of having PVD, the difference in calculation, subsidence observation, and numerical simulation between the mechanical properties before and after loading is significant, when using the mechanical data after loading then the results are quite close to the subsidence of observation and simulation rather than before loading. 

Detection of Insulation Defects in Automated In-Process Testing of Electric Wire during its Extrusion

2019 ◽  
Vol 942 ◽  
pp. 141-150
Author(s):  
Alexander Goldshtein ◽  
Galina Vavilova ◽  
Alexander Rumkin ◽  
Oldrich Starý
Keyword(s):  
Numerical Simulation ◽  
Mathematical Simulation ◽  
Physical Model ◽  
The Core ◽  
Process Testing ◽  
Capacitive Method ◽  
Simulation Results ◽  
Local Defects ◽  
Air Cavities ◽  
The Impact

The paper describes the electro-capacitive method for monitoring wire capacitance, which is implemented using the CAP-10 device, employed for in-process testing of the single core electric wire capacitance. Focus is made on the operating principle of the CAP-10 device. The possibility of using the CAP-10 device for detecting local defects in wire insulation is proved. Insulation defects such as foreign inclusions in the form of copper shavings, air cavities inside insulation and those at the core–insulation boundary are modeled. The impact of the defect geometric parameters on the wire capacitance measured during in-process testing is investigated through numerical simulation. Mathematical simulation results are validated through the physical model using the CAP-10 device.

Sign in / Sign up

Export Citation Format

Share Document