• Title/Summary/Keyword: Tread-pressure

Search Result 26, Processing Time 0.028 seconds

The Effect of Tread-Pressure on the Growth of Plantago asiatica Linne (답압이 질경이(Plantago asiatica Linne)의 생장에 미치는 영향)

  • Kim, In-Taek
    • The Korean Journal of Ecology
    • /
    • v.9 no.1
    • /
    • pp.91-101
    • /
    • 1986
  • To investigate the distribution of Plantago asiatica Linne, almost, restricted on the road-side, the plant growth analyzed by experimental cultivation under the condition of tread-pressure; 10 times/day (7.33kg/$cm^2$ ), 20 times/day (12.27kg/$cm^2$), 30 times/day (20.05kg/$cm^2$ ) and the control plot (1.68kg/$cm^2$ ). The matter production in the 10-time-per-diem plot (7.33kg/$cm^2$ ) of tread-pressure howed more large value than that inthe control one (1.68kg/$cm^2$ ) and those in the 20-0time-per-diem plot (12.27kg/$cm^2$ ) and the 30-time-per-diem one (20.05kg/$cm^2$ ) small values than that of the control plot. Especially, the growth of roots and spikes was extremely repressed. The number of leaves, scapes and lateral buds tend to increase in the tread-pressure of 20 times/day (12.27kg/$cm^2$ ) and 30 times/day (20.05kg/$cm^2$ ). The water contents of roots along the increase of tread-pressure to continuosly decreased. By the increase of tread-pressure, T/R ratio and C/F ratio their group decreased. The plant growth (7.33kg/$cm^2$ ) in the 10-time-per-diem plot increased more than that in the control one is regarded as the effect of tread-pressure affection on the road-side distribution of this plant.

  • PDF

The Effect of Tread-Pressure on the Growth of Kummerowia striata (답압이 매듭풀(Kummerowia Striata)의 생장에 미치는 영향)

  • Kim, In-Teak
    • The Korean Journal of Ecology
    • /
    • v.17 no.2
    • /
    • pp.149-157
    • /
    • 1994
  • To investigate the causes of distribution of Kummerowia striata (Thunb.) Schindl. mostly restricted on the roadside and reclaimed land, plant growth was analyzed under different of tread-pressures: $P_1$(10 times/day, $16.34Kg/cm^2$), $P_2$(20 times/day, $31.52 Kg/cm^2$), $P_3$(30 times/day, $40.79 kg/cm^2$) and the control $P_c$(0 times/day, $3.73 Kg/cm^2$). The matter production in the $P_1$decreased compared with that in the $P_c$, and those in the $P_2$and $P_3$ continuously decreased so that its length growth gradually decreased and, in particular, the growth of leaves and nodule was suppressed. The number of leaves and roots tended to increase in the $P_2$and $P_3$. The water contents of roots following the increase of tread-pressure increased continuously. Following the increase of tread-pressure, T/R ratio and C/F ratio tended to increase. Kummerowia striata showed the highest growth in the $P_c$ and showed 26% relative growth in the $P_1$compared with that in the $P_c$. This plant showed 8% relative growth in the $P_3$, which is excess to the tread-pressure $21Kg/cm^2$, the limit of growth in the plant. Because this plant grew continuously in the P$_3$, the tread-pressure is regarded as an important factor affecting the roadside distribution of this plant.

  • PDF

3-D Finite Element Mesh Generation of Tires Considering Detailed Tread Pattern (상세 트레드 패턴을 반영한 3차원 타이어 유한요소 격자 생성)

  • Cho, Jin-Rae;Kim, Ki-Whan;Hong, Sang-Il;Kim, Nam-Jeon;Kim, Kee-Woon
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.27 no.10
    • /
    • pp.1615-1622
    • /
    • 2003
  • Being contacted directly with. ground, the tire tread part is in shape of complex patterns of variable ASDs(anti-skid depth) to satisfy various tire performances. However, owing to the painstaking mesh generation job and the extremely long CPU-time, conventional 3-D tire analyses have been performed by either neglecting tread pattern or modeling circumferential grooves only. As a result, such simplified analysis models lead to considerably poor numerical expectations. This paper addresses the development of a 3-D tire mesh generation considering the detailed tread pattern and shows that the contact pressure and frictional energy distribution of tires considering the detailed pattern become better than those by the simplified tire model.

Finite Element Analysis on Standing Wave Phenomenon of a Tire Considering Tread Pattern (트레드 패턴을 고려한 타이어의 스탠딩 웨이브 현상에 대한 유한 요소 해석)

  • Kim, Kee-Woon;Jeong, Hyun-Sung
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.14 no.2
    • /
    • pp.76-83
    • /
    • 2006
  • Each tire has a critical speed at which a standing wave phenomenon occurs along the circumferential direction. If the standing waves are formed, the tire temperature is rapidly increased and it leads to tire failure eventually. As the formation of the standing waves is closely related to the tire stiffness, the effect of the tread pattern needs to be studied numerically. The standing wave phenomenon of a tire model with tread pattern is predicted by an explicit finite element method. The critical speed of the tire with tread pattern is in a good agreement with the experiment and is $15{\sim}20\;km/h$ lower than that of the tire without tread pattern. The effects of the inflation pressure and the vertical load on the critical speed are also investigated by using the tire model with tread pattern.

Failure Studies on the Wear Scars of an Automotive Tire (차량용 타이어의 마멸손상에 관한 고장사례 연구)

  • Lee, II-Kwon;Kim, Chung-Kyun
    • Tribology and Lubricants
    • /
    • v.23 no.5
    • /
    • pp.228-233
    • /
    • 2007
  • This paper presents the case studies on the friction related wears of an automotive tire, which is strongly connected to the safety and comfort of a driver during a running of a car. Wear scars of a tire tread are affected by various causes such as an air pressure, a wheel alignment, a driving speed, road conditions, starting and braking habits of a driver. The data were collected from used tires for a replacement at the car service center. Most of the wear problems came from the improper repair and adjustment of revolving components, which cause an unbalanced wear of a tread part of a tire. Thus, the regular checking of a tire radically reduces the wear scars of a tire and may increase a driving safety and a fuel economy of a car and a wear life of a tire.

Study on the frictional heat between wheel tread and brake shoe of EMU (도시철도 차량의 차륜답면-제륜자간 제동 마찰열에 관한 연구)

  • Yoon Cheon-Joo;Kim Seong-Keol;Goo Byeong-Choon
    • Proceedings of the KSR Conference
    • /
    • 2005.11a
    • /
    • pp.88-93
    • /
    • 2005
  • Frictional heat generates when the brake shoes are in contact with wheel tread under high pressure for EMU's speed control, stopping, and deceleration. Such a frictional heat has a significant effect on the wheel tread. In order to analyze the characteristics of frictional heat and measure the amount of the generated heat, tests by using a brake dynamometer and for running vehicles are carried out. In addition, finite element analysis is performed to simulate the temperature distribution and thermal analysis of the brake shoes. Through the tests and the simulations, it is found that the problems by temperature increase at tread braking are verified.

  • PDF

A Design of the Automation Tyre Tread State Check System based on IoT Service (IoT 서비스 기반 자동차 타이어 트레드 자동 점검 시스템 설계)

  • Kim, Minyoung;Choi, Donggyu;Jang, Jong-wook
    • The Journal of the Convergence on Culture Technology
    • /
    • v.6 no.4
    • /
    • pp.825-831
    • /
    • 2020
  • In modern society, automobiles have become an essential means of transportation. It is the only consumable that is worn by contacting the ground among automobile parts. If the tyres are severely worn, the tyres may be break, presenting a risk of a serious accident to the driver. To avoid this risk, drivers should check tyre pressure and tread condition before driving a car. Tyre inflation pressure can be easily measured by TPMS, but in the case of tyre tread conditions, it can be cumbersome when the driver measures it directly using a coin or vernier caliper. This hassle can expose the driver to traffic accidents due to tyre breakage by neglecting to measure the condition of the tyre tread. In this paper, we introduce the contents of research to design an IoT service-based system that can automatically measure automobile tyres, and we verified the possibility of realizing the system by actually implementing and testing some components of the system.

Damage Evaluation of Wheel Tread for High Speed Train Using Replication and Fracture Mechanics Characteristics (비파괴적 표면조직검사법과 파괴역학 특성에 따른 고속철도용 차륜 답면의 손상 평가)

  • Kwon, Seok-Jin;Lee, Dong-Hyung;Seo, Jung-Won;Kwon, Sung-Tae
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.31 no.7 s.262
    • /
    • pp.756-763
    • /
    • 2007
  • The majority of catastrophic wheel failures are caused by surface opening fatigue cracks either in the wheel tread or wheel flange areas. The inclined cracks at railway wheel tread are initiated and the cracks are caused by wheel damage-spatting after 60,000 km running. Because the failured railway wheel is reprofiled before regular wheel reprofiling, the maintenance cost for the railway wheel is increased. Therefore, it is necessary to analyze the mechanism for initiation of crack. In the present paper, the combined effect on railway wheels of a periodically varying contact pressure and an intermittent thermal braking loading is investigated. To analyze damage cause for railway wheels, the measurements for replication of wheel surface and the effect of braking application in field test are carried out. The result shows that the damages in railway wheel tread are due to combination of thermal loading and ratcheting.

A control and measurement system design for 3-axis pressure and 2-axis displacement on tire road interface (타이어 접지면의 3축방향 압력과 평면변위 측정을 위한 제어계측시스템의 설계)

  • Lim, Young-Cheol;Ryoo, Young-Jae;Cho, Gyu-Jong;Kim, Nam-Jeon
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.1 no.1
    • /
    • pp.58-62
    • /
    • 1995
  • Necessarily, it is required to analyze interfacial mechanism between tire and road for understanding tire wear, vehicle tracking and breaking. Therefore, there have been some efforts to measure 3-axis pressure and 2-axis displacement on tire road interface. But it was so hard to couple precisely measuring sensor and desired point on tire tread pattern block that it was impossible to analyze the mechanism on commercial tire with tread pattern. To overcome such a problem, a on-line measurement system is proposed in this paper. And an automatic control system is designed to test the tire with similar configuration of real vehicle driving.

  • PDF

A Study on the Development of Highly Efficient Sintered Brake Shoe in Railway Vehicle (철도 차량용 고성능 소결제륜자 개발에 관한 연구)

  • Ko, Kwang-Nam;Kim, Sung-Kwon;Kim, Sang-Ho;Kwon, Seok-Jin;Lee, Hi-Sung
    • Proceedings of the KSR Conference
    • /
    • 2011.10a
    • /
    • pp.986-993
    • /
    • 2011
  • The role of brake is safely to transport passenger & cargo and stop vehicles at emergency in railway vehicle. Brake system reduces the speed by control command of electricity or air. mechanical methods to perform brake are disk brake & tread brake. This study targeted development of highly efficient sintered alloy brake shoe in railway vehicle whose high frictional coefficient, wear resistance, compatibility of the existing tread brake shoe & minimization of wheel's thermal damage and performed development of friction material's formulation, analysis of pressure distribution in wheel tread & brake shoe, optimum form design through analysis of heat flow.

  • PDF