Prediction of hyperelastic material sealing pressure using experimental and numerical analyses

2019 ◽  
Vol 52 (8) ◽  
pp. 717-727
Author(s):  
T Sukumar ◽  
BR Ramesh Bapu ◽  
B Durga Prasad
Keyword(s):  
Contact Pressure ◽  
Operating Conditions ◽  
Experimental Results ◽  
Hyperelastic Material ◽  
Brake System ◽  
Test Rig ◽  
Stopping Distance ◽  
Braking System ◽  
Sealing Pressure ◽  
Fuji Film

In commercial vehicle air braking system, leakage is one of the major problems and will affect the performance of the vehicle braking in terms of brake pedal travel and stopping distance. If there is any leakage in the brake system, the vehicle stopping distance will not meet the safety regulations. One of the main reasons for braking system leakage is ineffective sealing mechanism. The majority of sealing elements used in the air brake system are O-rings, lip seals, and gaskets. This article presents an experimental procedure for measuring the sealing pressure between an O-Ring and its mating parts. The contact pressure measurement was performed in a static condition by means of an experimental test rig using Fuji film. For the sealing pressure study, a test rig was properly designed to replicate the actual operating conditions. Contact pressure was evaluated by means of Fuji film interposed between the O-ring and its mating parts. The sealing pressure tests were carried out for different clamping load conditions. The experimental results were compared with the numerical result using the finite-element analysis (FEA). A good correlation was found between the experimental and the numerical results. The outcome from the experimental results will be useful for finalizing the hyperelastic material models, which are input to the FEA for future reference.

Design and Manufacturing of a Clutch and Brake System for Indoor Tire Testing

2017 ◽  
Author(s):  
Aamir K. Khan ◽  
Corina Sandu
Keyword(s):  
Rolling Resistance ◽  
Brake System ◽  
Main Task ◽  
Test Rig ◽  
Braking Performance ◽  
Current Configuration ◽  
Braking System ◽  
Actuation System ◽  
Clutch System ◽  
Transmission Shaft

The primary goal of this work is to implement a clutch and brake system on the single tire Terramechanics rig of Advanced Vehicle Dynamics Laboratory (AVDL) at Virginia Tech. This test rig was designed and built to study the performance of tires in off-road conditions on surfaces such as soil, sand, and ice. Understanding the braking performance of tires is crucial, especially for terrains like ice, which has a low coefficient of friction. Also, rolling resistance is one of the important aspects affecting the tractive performance of a vehicle and its fuel consumption. Investigating these experimentally will help improve tire models performance. The current configuration of the test rig does not have braking and free rolling capabilities. This study involves modifications on the rig to enable free rolling testing when the clutch is disengaged and to allow braking when the clutch is engaged and the brake applied. The first part of this work involves the design and fabrication of a clutch system that would not require major changes in the setup of the test rig; this includes selecting the appropriate clutch that would meet the torque requirement, the size that would fit in the space available, and the capability to be remotely operated. The test rig’s carriage has to be modified in order to fit a pneumatic clutch, its adapter, a new transmission shaft, and the mounting frame for the clutch system. The components of the actuation system consisting of pneumatic lines, the pressure regulator, valves, etc., have to be installed. Easy operation of the clutch from a remote location is enabled through the installation of a solenoid valve. The second part of this work is to design, fabricate, and install a braking system. The main task is to design a customized braking system that satisfies the various physical and functions constraints of the current configuration of the Terramechanics rig. Some other tasks are: design and fabrication of a customized rotor, selection of a suitable caliper, and design and fabrication of a customized mounting bracket for the caliper. A hydraulic actuation system is selected, since it is suitable for this configuration and enables remote operation of the brake. Finally, the rig is calibrated for the new testing configurations.

Influence of Tire Operating Conditions on ABS Performance

2015 ◽  
Vol 43 (3) ◽  
pp. 216-241
Author(s):  
Srikanth Sivaramakrishnan ◽  
Kanwar Bharat Singh ◽  
Peter Lee
Keyword(s):  
Longitudinal Force ◽  
Operating Conditions ◽  
Force Response ◽  
Inflation Pressure ◽  
Vehicle Model ◽  
Tuning Parameters ◽  
Stopping Distance ◽  
Braking System ◽  
Antilock Braking System ◽  
Longitudinal Slip

ABSTRACT During its normal service life, a tire is subjected to large variations in operating conditions, such as ambient temperature, inflation pressure, and changes in tread depth. The longitudinal force response of the tire changes significantly because of each of these operating conditions. This, in turn, would directly influence the performance of the antilock braking system (ABS) installed in a vehicle. Current ABS systems are tuned for a vehicle with fixed operating thresholds that do not change. The objective of this study was to understand the influence of a tire's operating conditions on ABS efficiency and the extent of variation it can cause on stopping distance. This was done by obtaining longitudinal-slip characteristics for a given tire at various temperatures, inflation pressures, and tread depth through a traction trailer. These data were then used to simulate an ABS braking maneuver using a half-car vehicle model. The major reasons for the loss in stopping distance performance because of a drop in efficiency under each condition was then analyzed in detail. The latter part of this study explored the potential for improvement in stopping distance that could possibly be achieved through an intelligent ABS system that would use tire-sensed information, such as temperature, pressure, and tread depth to calculate essential tire characteristics in real time using an adaptive magic formula and change its tuning parameters accordingly.

Experimental and Analytical Investigation of High Speed Turbocharger Ball Bearings

2011 ◽  
Vol 133 (12) ◽  
Author(s):  
Ankur Ashtekar ◽  
Farshid Sadeghi
Keyword(s):  
High Speed ◽  
Ball Bearing ◽  
Analytical Investigation ◽  
Rotor System ◽  
Operating Conditions ◽  
Experimental Results ◽  
Test Rig ◽  
Angular Contact Ball Bearing ◽  
Turbine Wheel ◽  
Bearing Dynamics

The objectives of this investigation were to design and construct a high speed turbocharger test rig (TTR) to measure dynamics of angular contact ball bearing rotor system, and to develop a coupled dynamic model for the ball bearing rotor system to corroborate the experimental and analytical results. In order to achieve the objectives of the experimental aspect of this study, a test rig was designed and developed to operate at speeds up to 70,000 rpm. The rotating components (i.e., turbine wheels) of the TTR were made to be dynamically similar to the actual turbocharger. Proximity sensors were used to record the turbine wheel displacements while accelerometers were used to monitor the rotor vibrations. The TTR was used to examine the dynamic response of the turbocharger under normal and extreme operating conditions. To achieve the objectives of analytical investigation, a discrete element ball bearing model was coupled through a set of interface points with a component mode synthesis rotor model to simulate the dynamics of the turbocharger test rig. Displacements of the rotor from the analytical model were corroborated with experimental results. The analytical and experimental results are in good agreement. The bearing rotor system model was used to examine the bearing component dynamics. Effects of preloading and imbalance were also found to have significant effects on turbocharger rotor and bearing dynamics.

Tribogyr: A New Test Rig for High Spinning EHL Large Size Contacts

2007 ◽  
Author(s):  
H. Dormois ◽  
N. Fillot ◽  
G. Dalmaz ◽  
M. Querry ◽  
P. Vergne ◽  
...  
Keyword(s):  
Normal Load ◽  
Real Life ◽  
Operating Conditions ◽  
Experimental Results ◽  
Test Rig ◽  
Large Size

Only few studies have been published on EHD contacts that experienced simultaneously rolling, sliding and spinning motions. This paper describes a new test rig especially designed to simulate such operating conditions while imposing normal load and speeds as those found in real life mechanisms. Then, experimental results are presented and discussed.

Development of Automated Braking System for Collision Avoidance of Vehicles

2018 ◽  
Vol 10 (2) ◽  
Author(s):  
Vinod Handi ◽  
S. Jeyanthi ◽  
A. Giridharan
Keyword(s):  
Collision Avoidance ◽  
Distance Measurement ◽  
Ultrasonic Sensor ◽  
Experimental Results ◽  
Brake System ◽  
Braking System ◽  
Working Model ◽  
Frontal Collision ◽  
High Torque

The main objective of this paper is to develop an automated braking system to avoid frontal collision of the vehicle due to driver inattentiveness. The working model comprises of automated braking system which includes ultrasonic sensor, bike brake system, high torque motor, microcontroller, motor driver, battery, double acting cylinder and solenoid valves. An algorithm is proposed for automated braking system. The proposed working model is validated with experimental results. The ultrasonic sensor is validated for distance measurement and the sensor predicts the distance with an error of 3.31 percent.

Numerical simulation and experimental performance research of cylindrical vane pump

2021 ◽  
pp. 095440622110200
Author(s):  
Yiqi Cheng ◽  
Xinhua Wang ◽  
Waheed Ur Rehman ◽  
Tao Sun ◽  
Hasan Shahzad ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Rotational Velocity ◽  
Geometric Theory ◽  
Mechanical Efficiency ◽  
Operating Conditions ◽  
Experimental Results ◽  
Field Analysis ◽  
Total Efficiency ◽  
Three Dimensional Model ◽  
Vane Pump

This study presents a novel cylindrical vane pump based on the traditional working principle. The efficiency of the cylindrical vane pump was verified by experimental validation and numerical analysis. Numerical analysis, such as kinematics analysis, was performed in Pro/Mechanism and unsteady flow-field analysis was performed using ANSYS FLUENT. The stator surface equations were derived using the geometric theory of the applied spatial triangulation function. A three-dimensional model of the cylindrical vane pump was established with the help of MATLAB and Pro/E. The kinematic analysis helped in developing kinematic equations for cylindrical vane pumps and proved the effectiveness of the structural design. The maximum inaccuracy error of the computational fluid dynamics (CFD) model was 5.7% compared with the experimental results, and the CFD results show that the structure of the pump was reasonable. An experimental test bench was developed, and the results were in excellent agreement with the numerical results of CFD. The experimental results show that the cylindrical vane pump satisfied the three-element design of a positive-displacement pump and the trend of changes in efficiency was the same for all types of efficiency under different operating conditions. Furthermore, the volumetric efficiency presented a nonlinear positive correlation with increased rotational velocity, the mechanical efficiency showed a nonlinear negative correlation, and the total efficiency first increased and then decreased. When the rotational velocity was 1.33[Formula: see text] and the discharge pressure was 0.68[Formula: see text], the total efficiency reached its maximum value.

The μ Approach to Control of Active Magnetic Bearings

2002 ◽  
Vol 124 (3) ◽  
pp. 566-570 ◽  
Author(s):  
R. L. Fittro ◽  
C. R. Knospe
Keyword(s):  
Laboratory Test ◽  
Rotating Machinery ◽  
Vibration Response ◽  
Experimental Results ◽  
Magnetic Bearings ◽  
Pd Controller ◽  
Active Magnetic Bearings ◽  
Test Rig ◽  
Rotor Vibration ◽  
Multivariable Controller

Many important industrial problems in the control of rotating machinery with active magnetic bearings concern the minimization of the rotor vibration response to poorly characterized disturbances at a single or several shaft locations, these typically not corresponding to those of a sensor or actuator. Herein, we examine experimental results of a multivariable controller obtained via μ synthesis with a laboratory test rig. These indicate that a significant improvement in performance can be obtained with a multivariable μ controller over that achieved with an optimal decentralized PD controller.

Study of the Size Effects and Friction Conditions in Microextrusion—Part II: Size Effect in Dynamic Friction for Brass-Steel Pairs

2007 ◽  
Vol 129 (4) ◽  
pp. 677-689 ◽  
Author(s):  
Lapo F. Mori ◽  
Neil Krishnan ◽  
Jian Cao ◽  
Horacio D. Espinosa
Keyword(s):  
Grain Size ◽  
Friction Coefficient ◽  
Size Effect ◽  
Contact Pressure ◽  
Size Effects ◽  
Numerical Models ◽  
Kolsky Bar ◽  
Experimental Results ◽  
Material Response ◽  
Dynamic Coefficients

In this paper, the results of experiments conducted to investigate the friction coefficient existing at a brass-steel interface are presented. The research discussed here is the second of a two-part study on the size effects in friction conditions that exist during microextrusion. In the regime of dimensions of the order of a few hundred microns, these size effects tend to play a significant role in affecting the characteristics of microforming processes. Experimental results presented in the previous companion paper have already shown that the friction conditions obtained from comparisons of experimental results and numerical models show a size effect related to the overall dimensions of the extruded part, assuming material response is homogeneous. Another interesting observation was made when extrusion experiments were performed to produce submillimeter sized pins. It was noted that pins fabricated from large grain-size material (211μm) showed a tendency to curve, whereas those fabricated from billets having a small grain size (32μm), did not show this tendency. In order to further investigate these phenomena, it was necessary to segregate the individual influences of material response and interfacial behavior on the microextrusion process, and therefore, a series of frictional experiments was conducted using a stored-energy Kolsky bar. The advantage of the Kolsky bar method is that it provides a direct measurement of the existing interfacial conditions and does not depend on material deformation behavior like other methods to measure friction. The method also provides both static and dynamic coefficients of friction, and these values could prove relevant for microextrusion tests performed at high strain rates. Tests were conducted using brass samples of a small grain size (32μm) and a large grain size (211μm) at low contact pressure (22MPa) and high contact pressure (250MPa) to see whether there was any change in the friction conditions due to these parameters. Another parameter that was varied was the area of contact. Static and dynamic coefficients of friction are reported for all the cases. The main conclusion of these experiments was that the friction coefficient did not show any significant dependence on the material grain size, interface pressure, or area of contact.

Using Taguchi Experimental Design to Investigate Operating Variables That Significantly Affect Wear in Mud Pumps

1995 ◽  
Vol 209 (1) ◽  
pp. 29-40
Author(s):  
S H Mok ◽  
D G Gorman
Keyword(s):  
Experimental Design ◽  
Normal Load ◽  
Drilling Fluid ◽  
Operating Conditions ◽  
Taguchi Experimental Design ◽  
Drilling Mud ◽  
Test Rig ◽  
Offshore Drilling ◽  
Wear Rates ◽  
Operating Variables

Maintenance of offshore drilling mud pumps is normally based on running hours. It is generally accepted, however, that time does not provide an accurate means of scheduling maintenance, given the varying operating conditions of the reciprocating mud pumps. The energy expended at the interaction of sliding surfaces is hypothesized to be a better alternative. The effects of operating variables on wear rates are investigated. A Taguchi experimental design was used to identify those factors that significantly affect wear. Within the confines of an experimental test rig, the normal load and abrasive sand content was found to have a significant effect on the specific wear rate of nitrile rubber sliding on steel in drilling fluid.

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