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在研究轮胎—土壤关系所得的参数实际采用以前,为给定的越野条件选择尺寸、形状和结构都合理的轮胎必然会需要相当多的实际经验和技巧。获取这种实际可行的参数最合理的途径包括两个研究阶段:首先在实验室中作试验研究,然后进行野外试验。美军工程沃特韦试验站(WES)分析了在测力车和土壤槽装置上所作的大量单轮试验的数据,确定了土壤轮胎系统中最重要的独立参数,并把这些参数整理成了单个无因次的性能预测参数,轮胎的性能用下列系数来说明:运动阻力/负荷以及牵引力/负荷,下陷量/轮胎直径和扭矩/负荷×轮胎作用半径,后三项系数是于接近最大牵引力条件下测定的。在绝大部分情况下对轮胎性能试验中得出的土壤—单胎系统各无因次独立系数间的相互关系进行研究时,提出了预测参数的概念。对在各种各样的轮胎—土壤条件下所作试验室试验的结果作了分析。对在野外进行的各种强度的砂和粘土作了研究;也对轮胎作了研究:轮胎直径d从36到75厘米;宽度b从4到41厘米;表示轮胎形状的d/b值从1.1到18.0;表示轮胎柔软程度的变形率(即,在硬地面上轮胎的变形量/轮胎断面高度)从0.08到0.45;横断面近乎圆形和接近矩形的传统充气轮胎;充气轮胎与硬地面接触比压从14.5千牛顿/米~2到633千牛顿/米~2。针对砂提出了一个基本的无因次轮胎性能预测参数,而对粘土则另外提出了一个相似的参数。对上述大部分独立参数的所有变化范围内,这两个参数都能够很精确地预测单胎的性能。此外,在因次分析中所得出的多种样车模型的情况表明,所研究出的这种关系大多能够类推到各种各样的土壤—轮胎情况中去。逐步建立了的基本预测参数(在试验室中发展起来的)和轮式车辆野外试验性能数据之间的关系方程式,在对野外行驶条件下的土壤—轮胎系统进行定量时,这些方程式对我们有非常大的帮助,并且允许在给定的越野条件下合理选择和设计轮胎,使它能满足所要求的性能。
Prior to actual use of the parameters derived from tire-soil relationships, choosing tires of reasonable size, shape and texture for a given off-road condition would necessarily require considerable practical experience and skill. The most reasonable route to obtaining such practical parameters consists of two phases of research: first, conducting a pilot study in a laboratory and then conducting a field experiment. The U.S. Army Engineering Waterway Experimental Station (WES) analyzed data from a number of single-wheel tests conducted on load cell and soil trough devices, identified the most important independent parameters in the soil tire system and organized the parameters into a single Dimensionless performance prediction parameters, the performance of the tire with the following coefficients to illustrate: exercise resistance / load and traction / load, sag / tire diameter and torque / load × tire radius of action, the latter three coefficients are close to the maximum traction conditions Under the measured. In the vast majority of cases, the concept of predictive parameters was proposed when studying the interdependencies between the dimensionless and independent coefficients of soil-single-tire systems derived from tire performance tests. The results of laboratory tests conducted under a variety of tire-soil conditions were analyzed. Studies of tires were also conducted on various intensities of sand and clay that were carried out in the field; the tires were also studied: diameter d from 36 to 75 cm; width b from 4 to 41 cm; d / b values representing tire shape from 1.1 To 18.0; the deformation rate indicating the degree of softness of the tire (that is, the deformation of the tire on the hard ground / the height of the tire cross section) is from 0.08 to 0.45; the conventional pneumatic tire having a nearly circular and nearly rectangular cross section; The specific pressure is from 14.5 kN / m ~ 2 to 633 kN / m ~ 2. A basic predictive parameter for dimensionless tire performance is proposed for sand, while a similar parameter is proposed for clay. Both of these parameters predict the performance of a single tire very accurately over all changes in most of the above independent parameters. In addition, the multiple sample vehicle models derived from the analysis indicate that most of the relationships developed are analogous to the variety of soil-tire situations. The relationship equations between the gradually established basic prediction parameters (developed in the laboratory) and the field test performance data for wheeled vehicles, which are useful for quantifying the soil-tire system under field driving conditions, Very helpful and allows for the proper selection and design of the tire under given off-road conditions so that it meets the required performance.