曲率摩擦 的英文怎麼說
中文拼音 [qūlǜmócā]
曲率摩擦
英文
friction curvature-
The hyperbolic conservation laws with relaxation appear in many physical systems such as nonequilibrium gas dynamics, flood flow with friction, magnetohydrodynamics, etc. firstly, the thesis proves that there exists a unique global smooth solution for the cauthy problem to the hyperbolic conservation laws system with relaxation ; secondly, in the large time station, the thesis proves that the global smooth solutions of the hyperbolic conservation laws system with relaxation converge to rarefaction waves solution at a determined l ( p > 2 ) decay rate
帶鬆弛項的雙曲型守恆律組出現在諸多的物理系統中。例如,非平衡態的氣體動力學、帶摩擦的水流、磁動力學等。本文首先證明,帶鬆弛項的雙曲型守恆律組的柯西問題的整體光滑解的存在唯一性;其二,證明了帶鬆弛項的雙曲型守恆律組的解與相應的平衡態守恆律的稀疏波解在大時間狀態下的l ~ p衰減率。The sampling rate of the system can reach 3704 sps, and the crank angle is 1. 94 degree per sampling point corresponding to the crank speed of 1200r / min. in the mean time, the position signal of the piston could be collected by photo - electricity switch
本研究首先設計和實現了摩擦力採集電子電路系統,裝置最大采樣率可達到3704sps ,在曲軸轉速為1200r / min時,對應曲柄轉角1 . 94度采樣點,並且可以採集用來確定活塞位置的光電開關的信號。Based on the tribological principle and the theory of contact mechanics, it is feasible to adopt curvature - changing structure in the rock - bit journal bearing system. the structure and coupling relationship of curvature - changing journal bearing under the condition without friction have been analyzed and three kinds of sub - form structure configurations, namely, the pseudo - curvature - changing structure, the conformable curvature - changing structure, and the clearance curvature - changing structure, been differentiated according to the contacting features. the shape optimization and pre - running - in regulations of the contact surface of curvature - changing journal bearing under friction condition have been established. the results of rock bit journal bearing test indicate that the tribological behavior of the bearing can be effectively improved by curvature change based on both designing and pre - running - in
基於摩擦學原理和接觸力學理論,提出了可在牙輪鉆頭滑動軸承中採用變曲率結構.在不考慮摩擦的情況下,就結構設計和配合關系等問題進行了分析討論,劃分了準變曲率、吻合變曲率以及間隙變曲率等3種結構形式;針對考慮摩擦時的變曲率結構,提出了接觸形狀優化和預磨合的實施方案.鉆頭軸承試驗結果表明,無論是預設計變曲率還是預磨合變曲率,都能改善軸承摩擦副的摩擦學特性,因而值得進一步研究和推廣The results indicated that the dimension, shape and purity of base material could meet the functional demand of solid lubricant ; the thermal decomposition temperature of ptfe resin exceeds 400 c, but organic and inorganic packing filler added in ptfe made the water absorption rate of composite material increased, melting temperature and decomposition temperature decreased, in the meanwhile oxidative decomposition reaction was accompanied ; polar groups such as c = o, c - o - c and so on in the carbon fiber surface is advantageous to increase compatibility with other components and interlayer shearing strength ; uniform design experimental method could help to find the relationship between formula and frictional property by relatively small tests. the developing trend of each formula ' s friction coefficient could be showed by fitting curve ; the friction coefficient with no copper powder or graphite in formula was relatively big. this fact showed that copper powder and graphite should be used cooperatively ; it was found that when the ratio of copper powder to graphite by weight is 15 : 60, 30 : 30 - 40 and 60 : 15 - 30 respectively, the friction coefficient was relatively small. the degree of crystallinity of pure ptfe reached maximum by air cooling and the abrasion loss also reached maximum among three ones ; at the same time, the abrasion loss of solid lubricant sample was also the biggest among three ones ; when solid lubricant matched with 45 # steel axle or gcrl5 steel axle, lubricant transfer film could be formed on metal surface, thus direct contact between the surface of metal friction pair rings was reduced. their working life was elongated extremely ; there was mainly much graphite, a little ptff, moo3, feso4, cus and so on in lubricant transfer film
試驗結果表明:所選原料的尺寸、形狀及純度可滿足固體潤滑劑的性能要求;聚四氟乙烯樹脂熱分解溫度超過400 ,但在ptfe中加入無機填料會使復合材料吸水率提高,熔融溫度及分解溫度降低,且伴有氧化分解反應;碳纖維表面含有c = o及c - o - c等極性基團,有利於提高其與其它組分的相容性,提高層間剪切強度;均勻設計試驗方法能夠用較少的試驗次數找出配方與摩擦性能間的關系,擬合曲線基本能表示各配方的摩擦系數發展趨勢;配方中不加銅粉或不加石墨,其摩擦系數均較高,說明銅粉和石墨應該配合使用;當銅粉15份、石墨60份時,銅粉30份、石墨30 - 40份時,銅粉60 、石墨15 - 30份時,摩擦系數均具有較低值;純聚四氟乙烯樹脂在空氣冷卻時結晶度最大,磨損量也是三者中最大的;同時,固體潤滑劑試樣在空氣冷卻時的磨損量也是三者中最大的:不論是固體潤滑劑與45 #鋼軸配副或是固體潤滑劑鑲嵌入銅套后與gcr15鋼軸配副,在金屬表面均可形成潤滑轉移膜,從而減少金屬摩擦副表面間的直接接觸,大大延長其使用壽命;轉移膜中主要含有較多的石墨、少量聚四氟乙烯、 moo 。The authors present the review on dry sliding friction and wear behaviour of particle reinforced aluminum matrix composites in recent years, including friction behaviours, wear mechanisms and applications of these composites
離子注入是一種新興的束流表面強化技術,離子注入陶瓷材料可使其表面的力學性能如斷裂韌度、硬度、彎曲強度、摩擦學性能等得到改善,它為解決結構陶瓷韌性不足、摩擦磨損率較高等問題開辟了新的技術途徑。First super - low specific - speed centrifugal pump has a long and narrow flow passage for its high head and low capacity, and the power absorbed by disc friction is too high, so the efficiency is very low ; secondly the diffusion of flow passage is so high, that the reserved flow often emerges at the inlet and outlet of impeller. therefore the h ~ q characteristic curve is often hump - shaped, and at the low - capacity operating condition the instability often occurs ; thirdly the centrifugal pump at high - capacity operating condition is easy to overload because the n ~ q curve appears a rising trend
首先由於它的揚程較高、流量較小,所以它的流道狹長,圓盤摩擦損失較大,效率相對較低;其次由於它的流道擴散較嚴重,易在葉片進口產生迴流和在出口產生脫流,揚程流量特性曲線易出現駝峰,在小流量工況下易產生不穩定現象;第三,由於其功率流量曲線呈現上升趨勢,在大流量區運行時電機易過載。For different f, the effect of curvature and torsion on the flow structure, temperature distribution, the friction factor and nusselt number
不同的f下撓率和曲率對流動結構、摩擦系數和nusslt數的影響不同。( 2 ) with f varying, there exists a number fr which is about - 1 ( curvature, torsion and dean number have little influence on fr ), when f > fr, the maximum of the axial velocity is near the outside bent and the friction factor ratio increases with f increasing ; when f < fr, the maximum is near the inner side bent and the ratio increases with f decreasing ; when f = fr, the distributions of the axial velocity are similar to those of poiseuille flow and the friction ratio is about 1
( 2 )當f變化時,存在確定的數值fr ( fr在- 1左右。曲率、撓率和dean數對fr的影響很小) ,當f fr時,軸向速度最大值偏向外側,摩擦系數比隨f增大而增大;當f fr時,軸向速度最大值偏向內側,摩擦系數比隨f減小而增大;當f = fr時,軸向速度的分佈和poiseuille流近似相同,摩擦系數比約為1 。分享友人