Our recent experimental work showed that asymmetry is needed for surface textures to decrease friction in full-film lubricated sliding (e.g. thrust bearings) with Newtonian fluids; textures reduce the shear load and produce a separating normal force [1]. However, standard slider bearing theory cannot explain the sign of the observed normal thrust, and any effort to optimize surface textures wou...

The Electromagnetic Aircraft Launch System (EMALS) is being developed utilizing electrical and electronic technologies. EMALS is emerging in order to replace the existing steam catapult on naval carriers. Recently, the double-sided linear launcher has drawn increasing attention of researchers. This paper presents the design and analysis of the Linear Hybrid Reluctance Motor (LHRM). This new mot...

An alternative iterative computational procedure is proposed for internal normal ball loads calculation in statically loaded single-row, angular-contact ball bearings, subjected to a known thrust load, which is applied in the inner ring at the geometric bearing center line. An accurate method for curvature radii at contacts with inner and outer raceways in the direction of the motion is used. N...

A known iterative computational procedure is used for internal normal ball loads calculation in statically loaded single-row, angular-contact ball bearings, subjected to a known thrust load, which is applied in the inner ring at the geometric bearing center line. Numerical aspects of the iterative procedure are discussed. Numerical examples results for a 218 angular-contact ball bearing have be...

Compressible gas flow inside a convergent-divergent nozzle and its exhaust plume atdifferent nozzle pressure ratios (NPR) have been numerically studied with severalturbulence models. The numerical results reveal that, the SST k–ω model give the bestresults compared with other models in time and accuracy. The effect of changes in value ofdivergence half-angle (ε ) on the nozzle performance, thru...

allochthonous masses are common structures in zagros fold-thrust belt. they are generally considered as collapse structures formed by the influence of gravity and in rock units with competency contrast. however, large allochthonous masses mapped in dowgonbadan area in dezful embayment near the mountain front fault (mff) of zagros show characteristics different from the belt common collapse stru...

In this paper, some results are provided for minimum time roll about velocity vector maneuvering with thrust-vectoring and aerodynamic control in effect. The mathematical model for attitude motions of the aircraft is developed. First order necessary conditions for optimality using Pontryagen principle is applied, and the existence of an extreme family of solutions for the maneuver is shown. Mul...

Results from numerical and coldow experimental investigations of aerodynamic thrust vectoring on a small-scale aerospike thruster are presented. Thrust vectoring was created by the injection of a secondary uid into the primary ow eld normal to the nozzle axis. The experimental aerospike nozzle was truncated at 57% of its full theoretical length. Data derived from coldow thrust vectoring tests w...