Research on the Relationship between Driving Vibration Noise and Tire-Road Contact Pressure

CICTP 2017 ◽  
2018 ◽  
Author(s):  
Liyuan Liu ◽  
Zhang Chen ◽  
Xiao Zhang
Keyword(s):  
Contact Pressure ◽  
The Relationship ◽  
Vibration Noise

Tongue–Palate Contact Pressure, Oral Air Pressure, and Acoustics of Clear Speech

2013 ◽  
Vol 56 (3) ◽  
pp. 826-839 ◽  
Author(s):  
Jeff Searl ◽  
Paul M. Evitts
Keyword(s):  
Contact Pressure ◽  
Air Pressure ◽  
Speaking Rate ◽  
Clear Speech ◽  
Speech Acoustics ◽  
Relationship Of ◽  
The Relationship ◽  
Speech Clarity ◽  
Normal Speech ◽  
Listener Ratings

Purpose The authors compared articulatory contact pressure (ACP), oral air pressure (Po), and speech acoustics for conversational versus clear speech. They also assessed the relationship of these measures to listener perception. Method Twelve adults with normal speech produced monosyllables in a phrase using conversational and clear speech. Target phonemes were /t, d, s, z, l, n/. ACP was measured at a point of articulatory contact; Po was sensed by a catheter open in the posterior oral cavity. Results ACP was increased to a greater extent in clear speech for /t, d, z/. Po was increased to a greater extent for /t, d/. Acoustic changes also occurred in terms of segment durations, speaking rate, and CV dB ratio. Regression analysis indicated that segment duration was the strongest predictor of listener ratings of speech clarity, followed by an index of articulatory effort and speaking rate. Conclusion Articulatory effort, as indexed by ACP, Po, and CV dB ratio, was increased to varying degrees depending on the consonant. Greatest changes occurred for /t, d/. Durational measures at both the segment and the phrase level were also important for predicting listener ratings of speech clarity.

An analysis of shot peening

1983 ◽  
Vol 18 (2) ◽  
pp. 95-100 ◽  
Author(s):  
D A Hills ◽  
R B Waterhouse ◽  
B Noble
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Experimental Evidence ◽  
Contact Pressure ◽  
Shot Peening ◽  
Pressure Loading ◽  
The Relationship

It is shown that the residual stresses obtained during shot-peening are directly proportional to the treated material's hardness, and that the depth of material influenced depends on the velocity of approaching shot. The relationship between the shot size and depth hardened is developed, and experimental evidence is provided to verify the major points of the analysis. Useful curves, enabling the variation of residual stress with depth to be estimated, are included, and this enables the shot-peening treatment to be matched to alleviate any subsequent contact-pressure loading that the material may experience during service.

A Study of the Average Real Contact Pressure Between Rough Surfaces

2008 ◽  
Author(s):  
Robert L. Jackson ◽  
W. Everett Wilson ◽  
Santosh Angadi
Keyword(s):  
Fatigue Life ◽  
Contact Resistance ◽  
Contact Pressure ◽  
Current Work ◽  
The Real ◽  
Real Contact ◽  
Real Area Of Contact ◽  
Deterministic Methods ◽  
The Relationship ◽  
Real Area

It is well known that the friction, wear, fatigue life, and contact resistance (electrical and thermal) are dependent on the contact between the rough profiles of the surfaces. Several different techniques have been used to model this contact (fractal, wavelet, statistical, multiscale, and deterministic methods). Several of these methods have found that the relationship between the real area of contact and load is linear. This suggests that there is a constant contact pressure between two surfaces (the average real contact pressure). Somewhat surprisingly, several works have found that this pressure may be greater than traditional hardness, even when the contact is heavily loaded and the contacts are deforming plastically. This mechanism is often called the asperity persistence. The current work uses a recent multiscale contact model and other theories to explain this mechanism and to help predict the average real contact pressure, especially during heavily loaded contacts.

Research on Contact Deformation Experiments in Stiffness Measurement of Spring Tubes

2010 ◽  
Vol 44-47 ◽  
pp. 3818-3822
Author(s):  
Yun Feng Li ◽  
Zheng Hua Ma ◽  
Guang Lin Wang
Keyword(s):  
Contact Angle ◽  
Contact Problem ◽  
Numerical Method ◽  
Contact Pressure ◽  
Error Compensation ◽  
Contact Deformation ◽  
Stiffness Measurement ◽  
Pressure Profiles ◽  
The Relationship

Contact deformation experiments in stiffness measurement of spring tubes are studied in this paper. Firstly, Herzian catact theory, Person method and one numerical method are proposed to solve the contact problem based on the character of the contact in spring tube stiffness measurement. Secondly, the normalized pressure profiles and the relationship between non-dimensionalized contact pressure and contact angle are taken to study three contact theories. Lastly, it’s proved by some error compensation experiments that Persson method and the Numerical method are more conformable to solve closely conformal problem.

Vibration Monitoring and Damage Quantification of Ball Bearings for Household Appliances

2005 ◽  
Author(s):  
F. K. Choy ◽  
D. Konrad ◽  
E. Labus ◽  
R. Wu
Keyword(s):  
Vibration Monitoring ◽  
Ball Bearings ◽  
Household Appliances ◽  
Rejection Level ◽  
Bearing Assembly ◽  
Bearing Vibration ◽  
Vibration Signatures ◽  
The Relationship ◽  
High Rejection ◽  
Vibration Noise

The main objective of this paper is to determine the relationship between bearing vibration/noise and the amount of flaws existed in a ball bearing assembly. In this study, 30 “good” and 30 “bad” typical ball bearings used for transmissions in household appliances are used for experimental vibration testing and measurements of flaws. While the “good” bearings are obtained form the lot of bearings tested for acceptable noisy level and the “bad” bearings are obtained from the lot with high rejection level. Although some irregularities are found in the ball elements, but most of the flaws are found in the outer races of the “bad” bearings. The levels of the flaws are measured using micrometers and vibration levels of the bearings are obtained from the accelerometers attached to the bearing supports at the bearing test rig. Time domain, frequency domain, and chaotic vibration signatures for the bearing are examined to correlate with the levels of flaws in the outer races of the bearings. The results from the FFT spectra show that the average vibration amplitude of the “bad” bearing is about 5 times higher than those of the “good” bearings.

Combustion Microstructures and Frictional Ignition Resistance of Ti-6Al-4V Titanium Alloy

2019 ◽  
Vol 944 ◽  
pp. 127-134
Author(s):  
Guang Bao Mi ◽  
Xu Huang ◽  
Jing Xia Cao ◽  
Bao Wang ◽  
Chun Xiao Cao
Keyword(s):  
Titanium Alloy ◽  
Contact Pressure ◽  
Heat Affected Zone ◽  
Ignition Temperature ◽  
Parabolic Law ◽  
Composite Oxides ◽  
Critical Ignition ◽  
Flow Pressure ◽  
Relationship Of ◽  
The Relationship

The effects of the contact pressure Pfric and the oxygen concentration c0 on the ignition resistance of Ti-6Al-4V were studied by friction in oxygen-enriched atmosphere. The relationship of Pfric-c0 was built to quantitatively describe the ignition resistance, the combustion microstructures were investigated by XRD, SEM and EDS. Further, the principle of improving the ignition resistance was proposed. It indicates that the relationship of Pfric-c0 obeys parabolic law. The c0 decreases by 4% when the Pfric increases from 0.1MPa to 0.25MPa, manifesting that the ignition resistance depends on c0 strongly (or equivalent flow pressure Peq). The ignition resistance of Ti-6Al-4V is 42.9% of that of TB12. When Peq varies from 0.1~0.5MPa, the critical ignition temperature Т* is approximate to 568~461K. Violent sparks form during frictional ignition. The low ignition resistance of Ti-6Al-4V probably results from not only the composite oxides of TiO2, Al2O3 and V2O5 generating during ignition which could not prevent the rapid interaction between Ti and O, but also the Al and V elements in the heat-affected zone which could not stop or slow the massive diffusion of O towards the alloy.

Oil film thickness analysis of the sealing surface for hydraulic rotary rectangular vane actuator

2018 ◽  
Vol 70 (8) ◽  
pp. 1494-1499
Author(s):  
Han Qing ◽  
LiangXi Xie ◽  
Lu Li ◽  
Chuang Jia
Keyword(s):  
Numerical Model ◽  
Film Thickness ◽  
Contact Pressure ◽  
Reynolds Equation ◽  
Distribution Curve ◽  
Contact Pressure Distribution ◽  
Content Type ◽  
Oil Film ◽  
Rotary Actuator ◽  
The Relationship

Purpose This paper aims to establish a numerical model to calculate contact pressure for rectangular vane sealing surface of hydraulic rotary actuator. Numerical model can be applied to solve the steady-state Reynolds equation after the oil film thickness and the contact pressure distribution curve of the vane sealing surface are obtained. Design/methodology/approach The authors established the numerical model of contact pressure base on the theory of elastic after, the Reynolds equation is solved by the inverse solution. Findings The relationship between the oil film thickness of vane sealing surface and the contact pressure on different sealing location for hydraulic rotary actuator is obtained. At the same time, the lubrication state on the surface of seal is also found when the hydraulic rotary actuator runs stably. Originality/value The study shows that the lubricating state of the vane sealing surface is mixed lubrication, when the rotor of the hydraulic rotary actuator is running stably at a certain speed. Meanwhile, this research will provide a theory basis for later experiment for the hydraulic rotary vane actuator.

Finite element simulation on clothing pressure and body deformation of the top part of men’s socks using curve fitting equations

2015 ◽  
Vol 27 (2) ◽  
pp. 207-220 ◽  
Author(s):  
Mei Zhang ◽  
Henan Dong ◽  
Xuerong Fan ◽  
Rui Dan
Keyword(s):  
Functional Equation ◽  
Finite Element ◽  
Contact Pressure ◽  
Cross Section ◽  
Curve Fitting ◽  
Lower Leg ◽  
Quadratic Functional ◽  
Content Type ◽  
The Relationship ◽  
Variation Tendency

Purpose – Objective appraisal of pressure comfort is the basement of optimal design of clothing. The purpose of this paper is to study a new method to appraise pressure comfort through displacement distribution, and then explored the multiple relationship between pressure and displacement on the lower leg cross-section using finite element method (FEM) and curve fitting. Design/methodology/approach – This paper presented a 2D simulation model of the lower leg cross-section consisting of three layer different mechanical properties, namely skin, soft tissue, and bone. Analyzed the relationship and variation tendency between contact pressure and strain, calculated the multiple relationship between pressure and displacement on the lower leg cross-section where located at the top part of men’s socks in detail, and then obtained the quadratic functional equation between angle and pressure/displacement ratio through segmented curve fitting using Origin 7.5 software. Findings – In this research work, the mathematical equation is obtained which describe the relationship between angle and pressure/displacement of the top part of men’s socks. On the premise of the known contact pressure values on the lower leg cross-section, the corresponding displacement values on the human body surface can be obtained by the functional equation under stress, and this displacement could be used as an objective evaluation index for pressure comfort. Based on these conclusions, the authors could provide theoretical reference for pressure prediction and optimizing the design of clothing. Research limitations/implications – This paper is unconcerned with the simulating of pressure, strain, and displacement distribution when dressing during the course of walking and running. Originality/value – The paper analyzed the relationship and variation tendency between contact pressure and strain using FEM, and then obtained the quadratic functional equation between angle and pressure/displacement ratio of the top part of socks. It can supply a new method to appraise pressure comfort.

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