The dissipation rate of turbulent kinetic energy () and shear rate (γ) are the key process parameters for mixing in surface aerators. At constant dynamic variables (rotational speed), both  and γ are greatly affected by the geometric parameters (impeller diameter, cross-sectional area of the tank, liquid height, rotor blade length and immersion height). By doing numerical computation by VISIM...

The effectiveness of surrogate based optimization of helicopter rotor blades for vibration reduction using kriging global approximations is investigated. The search for the optimal design is conducted using two methods: (1) the “one-shot” approach in which the surrogate is optimized directly and (2) a method based on the expected improvement function which seeks to find optimal designs while re...

This paper presents a methodology for threedimensional numerical simulations of supercooled water droplet trajectories through aeroengine rotating machinery. Both flow and droplets’ governing equations are formulated and solved in the reference frame of rotating blades. A Eulerian-Lagrangian approach is used for the continuous and discrete phases with one-way interaction model to simulate the a...

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This paper investigates the use of disturbance models in the design of wind turbine individual pitch controllers. Previous work has used individual pitch control and disturbance models with the Multiblade Coordinate Transformation to design controllers that reduce the blade loads at the frequencies associated with the rotor speed. This paper takes a similar approach of using a disturbance model...

Design and manufacturing of a high performance micro-hydro-kinetic turbine is discussed in the present paper. The main goal is manufacturing an equipped experimental model of hydro-kinetic turbine with highest energy absorption from water current. A multi-shape ducted turbine comprised of a multi-part diffuser was manufactured that can be converted to many experimental models for studying vario...

Characteristics of rotor blade tip clearance flow in axial compressors can significantly affect their performance and stable operation. It may also increase blade vibrations and cause detrimental noises. Therefore, this paper is contributed to investigate tip leakage flow in a low speed isolated axial compressor rotor blades row. Simulations are carried out on near-stall condition, which is val...

The cause of crack initiation turbine blade had initially cracked by a fatigue mechanism over a period of time and then fractured by the overload at the last moment. Experimental procedure consists of macroscopic inspection, material verification, microscopic examination, and metallographic analysis and finally FE. And for these procedures, some specimens were prepared from a fractured blade. Us...

This paper is concerned with the statistical model development issues, necessary for rapid estimation of the rotor sizing for single main rotor helicopters at the preliminary design stage. However, Central Composite Design (CCD) method, simulation-based data collection, linear regression analysis, mathematical modelsdevelopmentand validations through the analysis of variance (ANOVA) were perfor...