
Accession Number : AD0711073
Title : STRESSES AND DEFORMATIONS IN MULTIPLY AIRCRAFT TIRES SUBJECT TO INFLATION PRESSURE LOADING.
Descriptive Note : Technical rept. Aug 68Dec 69,
Corporate Author : AIR FORCE FLIGHT DYNAMICS LAB WRIGHTPATTERSON AFB OHIO
Personal Author(s) : Brewer,Howell K.
Report Date : JUN 1970
Pagination or Media Count : 215
Abstract : The pneumatic tire casing is treated as a laminated, anisotropic, toroidal shell of revolution possessing bending rigidity. The plies are considered to be homogeneous orthotropic laminae on a macroscopic scale, which are constructed of elastic textile cords embedded in an elastic rubber matrix. Modern micromechanics theory, which is based on the selfconsistent model of composite materials, is used to calculate the four basic elastic moduli of a single lamina. The tire shell is considered to deform according to the classical Love hypothesis. The equilibrium, straindisplacement, and laminate constitutive equations governing the tire shell are reduced to a system of six first order ordinary differential equations with variable coefficients. A multisegment, forward integration technique is used which first transforms the two point boundary value problem into an equivalent set of initial value problems which can then be integrated numerically with a fourth order RungeKutta routine. The finite displacements are taken into account by an incrementing process which builds up the total solution as sequence of linearized solutions. The theory and solution technique is illustrated by means of a numerical example. The tire chosen for this purpose is a 32 x 8.8 Type VII aircraft tire. A complete set of numerical data is presented. The calculations were verified experimentally by measuring tire strains and the inflated tire meridian profile. The agreement between theory and experiment is good. (Author)
Descriptors : (*AIRCRAFT TIRES, STRESSES), ELASTIC PROPERTIES, MODULUS OF ELASTICITY, NUMERICAL ANALYSIS, SHEAR STRESSES, ELASTIC SHELLS, FORCE(MECHANICS), STRAIN(MECHANICS)
Subject Categories : Aircraft
Distribution Statement : APPROVED FOR PUBLIC RELEASE