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This study aims to analyze the dynamic performance of aerostatic thrust bearing for different geometries of recess. Different geometries of recess of equal recess area, i.e. circular, elliptical, rectangular and annular, have been considered in analysis. The work also analyzes the influence of tilt angle on the performance of thrust bearing. To compute the unknown pressure field, the Reynolds equation governing the flow of compressible lubricant (air) has been solved using finite element formulation. Further, separate finite element formulations have been carried out to compute fluid film stiffness and damping coefficients directly. This method provides quick computation of stiffness and damping coefficients of aerostatic thrust bearing than the usual approach.

As the Reynolds equation governing the flow of compressible lubricant is nonlinear partial differential equation, the computation of the stiffness and damping coefficient follows an iterative procedure. It requires a lot of computational energy. Therefore, in the present work, a novel technique based on finite element formulation is suggested to compute air film stiffness and damping coefficient in aerostatic thrust bearing.

A novel technique based on finite element formulation is illustrated to simulate the performance of tilted pad aerostatic thrust bearing. On the basis of simulated results, following key conclusions may be drawn. The static and dynamic performance of a circular aerostatic tilted thrust pad bearing is significantly affected with a change in the value of tilt parameter and the shape of the recess.

Implications are as follows: direct computation of air film damping coefficient is performed without perturbation method in finite element method (FEM); influence of tilt on aerostatic thrust bearing is studied; influence of recess shape on aerostatic thrust bearing is observed; and finite element formulation of aerostatic thrust bearing is performed.

The present work will be quite useful for bearing designer and academicians.

The production of commodities from renewable organic material has gained enormous interest due to the rising public understanding of conscious development. Natural fibers are accessible in environment, and their parameters depend on their physical traits and chemically engineered makeup. Grewia optiva (GO) comes under the category of bast fibers, also known as Bhimal. This study aims to realize the consequences of alkali treatment on the characterization of natural fibers, their developed yarn and then the woven mat.

Raw fiber was treated with 20% alkali solution. After treatment, it was evaluated for changes in the general laboratory system. This treatment is known as mercerization, through which the parameters of cellulose fibers can be enhanced. After this process, the content of cellulose increases due to the removal of the hydroxyl group. The removal of microfibrils, hemicellulose and the introduction of hydrogen bonds increase the interactive capacity of fiber. The job was divided into different sections, including acquiring fiber, developing yarn and creating a mat.

The quality of the surface of the fiber was enhanced after the treatment. Its diameter was reduced to 54.72 microns. In the developed woven mat, it was densified using water treatment and attained grams per square meter (GSM) of 389.7.

The usage of mercerization softens the fiber to twist into yarn, which is finally woven into a mat. Treatment of fabric or mat makes it denser to impart better strength. A woven mat of natural fibers provides maximum strength to the composites.

The purpose of this paper is to study theoretically the combined influence of journal misalignment and wear on the performance of a hole‐entry hybrid journal bearing system. The bearing is assumed to be operating in a turbulent regime.

The modified Reynolds equation based on Constantinescu lubrication theory has been solved by using finite element method together with orifice and capillary restrictors flow equations as a constrain together with appropriate boundary conditions.

It has been observed that for a symmetric hole‐entry journal bearing configuration the value of h¯_min is more for the bearing compensated by orifice restrictor as compared to capillary restrictor when bearing operates in turbulent regime under worn/unworn conditions. From the point of view of stability threshold speed ω¯_th, the reduction in the value of ω¯_th for capillary compensated bearing is around −3.89 percent whereas for orifice compensated bearing it is −7.85 percent when misaligned worn bearing is operating in turbulent regime.

The present work is original of its kind, in case of misaligned hole‐entry worn journal bearing. The results are quite useful for the bearing designer.

The present work aimed to study analytically the influence of wear on the performance of a capillary-compensated hole-entry hybrid misaligned journal bearing system operating in a turbulent regime. The numerically simulated results are presented for the chosen values of restrictor design parameter, Reynolds numbers, wear depth and misalignment parameters.

The wear caused on the bearing surface due to start/stop operations is modeled using the Dufrane’s abrasive wear model. The modified Reynolds equation based on Constantinescu’s lubrication theory is solved using finite element method together with capillary restrictor flow equation.

It is found that the value of minimum fluid-film thickness increases significantly for a constant value of restrictor design parameter when unworn aligned bearing operates in turbulent regime vis-à-vis laminar regime. Further, it has also been observed that when a worn bearing operates in laminar/turbulent regimes, the reduction in the value of minimum fluid-film thickness is more due to journal misalignment as compared to the aligned bearing operates in laminar regime.

The present work is original concerning the performance of worn hole-entry hybrid misaligned journal bearing system operating in turbulent regime. The results are expected to be quite useful for the bearing designer.