A small wind turbine blade was designed and optimized in this research paper. The blade plays an important role, because it is the most important part of the energy absorption system. Consequently, the blade has to be designed carefully to enable to absorb energy with its greatest efficiency. The main objective of this paper is to optimized blade number and selection of tip speed ratio corresponding to the solidity. The power performance of small horizontal axis wind turbines was simulated in detail using blade element momentum methods (BEM). In this paper for wind blade design various factors such as tip loss, hub loss, drag coefficient, and wake were considered. The design process includes the selection of the wind turbine type and the determination of the blade airfoil, twist angle distribution along the radius, and chord length distribution along the radius. A parametric study that will determine if the optimized values of blade twist angle and chord length create the most efficient blade geometry. The 3-bladed, 5-bladed and 7-bladed rotor achieved maximum values of Cp 0.46, 0.5 and 0.48 at the tip speed ratio 7, 5 and 4 respectively. It was observed that using BEM theory, maximum Cp varied with strongly solidity and weakly with the blade number. The studies showed that the power coefficient increases upto blade number B = 5, while the blade number if increased above 5 then the power coefficient decreases at operating pitch angle equal to 3°. Highest Cp would have solidity between 4% to 6% for number of blade 3 and design point tip speed ratio of about "7". Highest Cp would have solidity ranging from 5% to 10% for number of blade 5 and 7 and design point tip speed ratio of about 5 and 4 respectively.

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This paper aims to optimize and investigate the small horizontal axis wind turbine blades at low wind speed. The objective of this research work is to explain the design method based on BEM theory for 0.2 m blade rotors with constant, variable and linear chord with twisted blade geometry. MATLAB and Xfoil programs were used for BEM principles and wind turbines with SG6043 airfoil. A numerical and experimental study was carried out to examine the impact of rotor solidity from 0.057 to 0.207 and the number of blades from 3 to 7 in this research work. The experimental blades were developed by using the 3D printing additive manufacturing technique. The investigation of the rotors has been done in an open wind tunnel, at wind speed from 2 to 8 m/s. The initial investigation range included tip speed ratios from 2 to 8, and angle of attacks from 2 to 20°. Later on these parameters were varied in Matlab and Xfoil software optimization and investigation of the power coefficient, blade geometry, number of blades and blade pitch angle. It was found that the rotor solidity 0.055 to 0.085 displayed better performances.

In this research paper, the main focus on small wind turbine blade performance of two mixed airfoil such as SG 6043 and NACA 4412 and different composite materials are compared by using Numerical with software analysis. The aerodynamic geometry and materials of blade are key parameters to determine staring of the wind turbine and performance of the rotors. The best selection of airfoil and material gives better performance of the wind turbine blade design based on the available wind velocity, Reynolds number. The author wants to compare the performance of mixing for airfoils (SG 6043 and NACA 4412) at Low Reynolds number; less than 250,000. A parametric numerical study and Simulation was conducted, in order to determine the optimum distribution of chord length and twist angle along the 1 m length of the blade at rated wind speed of 8 m/s. A Blade Element Momentum (BEM) theory based on MATLAB program was developed. The numerical simulation is carried out by Matlab and X-Foil software. The lift-drag ratio are compared based on different angles of attack 2º, 4º, 6 o , 8º, 10º at wind velocity 8m/s, rated wind velocity for rural areas. The design chord length of the blade is 1 m and width of thewing is 0.311m. The numerical results from Matlab are compared with the results of X-Foil software; by doing this simulation, understand their blade geometry optimization and the performance of two mixing airfoil profiles is compared. Therefore, the best airfoil will be used in small horizontal axis wind turbine in rural areas where the wind velocity is less. The main focus in this research paper is Reynolds number effect, axial induction effect, Tip loss, Drag effects were considered in the aerodynamic shape optimization and maximized Power coefficient by varying the different of blade sections with optimized tip speed ratio (TSR).

Employee retention has been a key factor for the sustainable operation of any organization. Among all the sectors of an economy, banking sector has been one of the sectors with higher employee turnover. This study aims to investigate retention issues in Civil Bank and Mega Bank limited located in Kathmandu valley. The study has collected data from 132 employees (from different levels and different departments working in   these   commercial   banks   through   5-point   Likert questionnaire and processed with the help of SPSS. The collected data are analyze using descriptive statistics and regression analysis. The study results show that workplace environment, career growth & development opportunity, compensation management and job security have significant impact and association with the employee’s retention in Civil Bank and Mega Bank located in Kathmandu. It is recommended that plan for work life balance and better career planning for the employees could increase to establishing the stability of employees working in banking sectors.