Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Modal–Cotton Fibre Blend Ratio and Ring Frame Parameter Optimisation Through the Taguchi Method

Maheswaran R, Srinivasan V

Autex Research Journal

2019

Vol. 19, no. 1

86--96

The influence of Modal–cotton (MC) fibre blend ratio and ring frame machine parameters such as front top roller loading and break draft on the blended yarn properties has been studied. Compact MC blended yarn samples of 14.75 tex with three different MC fibre blend ratio has been produced in a LR 6 ring spinning frame fitted with Suessen Compact drafting system. A robust design optimisation to minimise the variations of the output yarn properties such as blended yarn tenacity, yarn unevenness and hairiness caused because of the variations in the material as well as machine setting parameters is achieved through the Taguchi parametric design approach. It is found that the maximum compact MC blended yarn tenacity is 23.76 g/tex, which is influenced very much by MC fibre blend ratio but meagrely by top roller loading and break draft. Similarly, the minimum 9.54 U% and 3.59 hairiness index are achieved with 100:0 and 70:30 MC fibre blend ratio, respectively, at 23-kg top roller loading. Statistical ANOVA analysis is performed on the results and optimum values are obtained within the 95% confidential level through confirmation experiments.

CFD analysis of aerofoil using dimples and prevent radar signals using stealth technology

Maheswaran R., Manikandan R.

Archives of Materials Science and Engineering

2016

Vol. 77, nr 2

72--77

Purpose: The main objective of aircraft aerodynamics is to enhance the aerodynamic characteristics and maneuverability of the aircraft. This enhancement includes the reduction in drag and stall phenomenon. The airfoil which contains dimples will have comparatively less drag than the plain airfoil. Introducing dimples on the aircraft wing will create turbulence by creating vortices which delays the boundary layer separation resulting in decrease of pressure drag and also increase in the angle of stall. In addition, wake reduction leads to reduction in acoustic emission. The overall objective of this paper is to improve the aircraft maneuverability by delaying the flow separation point at stall and thereby reducing the drag by applying the dimple effect over the aircraft wing. Design/methodology/approach: This project includes computational analysis of dimple effect on aircraft wing, using NACA 0018 airfoil. Dimple shapes are circular which locates the inward, outward are selected for the analysis; airfoil is tested under the inlet velocity of 30m/s at different angle of attack (-5°, 0°, 5°, 10°, and 15°). Findings: This analysis favors the dimple effect by increasing L/D ratio and thereby providing the maximum aerodynamic efficiency, which provides the enhanced performance for the aircraft. Practical implications: Stealth technology is based on the principle of reflection and absorption that makes the objects’ observability lower and stealthy. A 'stealth' vehicle will generally have been designed from the motive to reduce RCS (Radar Cross Section) of aircrafts i.e. radar signature of aircrafts.