Hydrokinetic turbine performance depends on different parameters such as BLADE geometrical parameters (i.e. chord length, BLADE PITCH ANGLE, hydrofoil shape, BLADE yaw ANGLE etc.) Kinematic parameters (i.e. water speed, rotational speed etc.) and other important parameters include tip speed ratio (TSR) and the location of turbine in the channel or river bed. In this project Computational fluid dynamics (CFD) and commercial software ANSYS Fluent 16 are used to simulate hydrokinetic turbine.In numerical simulation multiple reference frame (MRF) model and the shear -stress transport k-w SST turbulence model are used. The grid independency is studied to ensure of numerical results. Also, the results are validated with experimental data. At first, to investigate the effect of BLADE PITCH ANGLE and chord length on power coefficient, three different chord lengths were considered and BLADE PITCH ANGLE over a range of BLADE PITCH ANGLEs (0o to 16o) with TSR (2.17 to 6.22) are studied. The results show that maximum power coefficient was found at 10o BLADE PITCH ANGLE with 1.676 cm chord length. Based on the results, stall delay depends on BLADE PITCH ANGLE and chord length.

Investigation of the effects BLADE PITCH ANGLE on noise emission from a horizontal axis wind turbine is the goal of this paper. To understand the flow around BLADE wind turbine, and to reduce noise emission in order to respect noise regulation, especially a residential area, three different PITCH ANGLEs 0° , 3° , and 6° are tested, using computational aerodynamic and aero acoustic methods. Three dimensional flow simulations are carried out with two unsteady CFD simulations URANS, DES used to calculate the near-field flow around a HAWT of NREL Phase VI small scale. The far field noise is predicted from the simulated sources by the Ffowcs William and Hawkings analogy, and compared and validated with available test data for a small-scaled model of the NREL Phase VI. The comparison demonstrates a generally good agreement between DES predicted and measured noise levels. It can be seen that the noise emission increases by decreasing PITCH ANGLE. Moreover, the PITCH ANGLE control has a significant effect on the noise emission especially in the intermediate frequency range. We show that it is possible to reduce the noise level by control PITCH ANGLE without losing too much the power.

The Darrieus lift-based VAWT has been studied by many scientists due to its simplicity of design and the wind direction independency. Due to increasing ANGLE of attack and dynamic stall at low tip speed ratios, these wind turbines have the inherent problem of self-starting inability and produce less power's compared to that of horizontal axis wind turbines. In this study, the effects of variable BLADE PITCH ANGLE mechanism on decreasing dynamic stall have been investigated. Finally, a PITCHing system (variable PITCH Darrieus-type wind turbine) has been proposed, which can reduce both the BLADEs, oscillating motion and the magnitude of the ANGLE of attack in one revolution, compared to that of conventional VAWT. In this study, unsteady two-dimensional simulation is conducted, using CFD with moving mesh the rotating rotor. Simulation of different preset PITCH ANGLEs of ±3° and ±6°, ±9° and ±12°, it is concluded that adjustment of PITCH ANGLE about -3°, causes a delay in flow separation and control dynamic stall. It was also observed that a variable-PITCH BLADE turbine can suppress flow separation on its BLADEs at low tip speed ratios. This leads to delay or elimination of dynamic stall and results in a higher efficiency during the range of turbine operation compared to that of fixed-PITCH BLADE Darrieus turbines.

Impellers with splitter BLADEs are used for pumps and compressors in the design of turbomachines. Design parameters such as the number of BLADEs, BLADE discharge ANGLE and impeller discharge diameter impact affect pump performance and energy consumption. In this study, the effect of the number of BLADEs (z=5, 6, and 7), BLADE discharge ANGLEs (β 2b=25 , and β 2b=35 ) and splitter BLADE lengths (40, 55, 70, and 85% of the main BLADE length) on Deep Well Pump (DWP) performance has been studied experimentally. In the experiments, pump casing, BLADE inlet ANGLE, BLADE thickness, BLADE width and impeller inlet and discharge diameters have been kept fixed while other parameters such as the number of BLADEs, BLADE discharge ANGLEs and splitter BLADE lengths have been allowed to vary. As a result of the experimental study, the highest efficiency of all the impellers for best efficiency point (b. e. p) has been obtained on the impeller with the number of BLADEs z=6, BLADE discharge ANGLE  2b=25 and 85% splitter BLADE addition compared to impellers without splitter BLADEs.

The effective utilization of wind energy conversion system (WECS) is one of the most crucial concerns for the development of renewable energy systems. In order to achieve appropriate wind power, different PITCH ANGLE methods are used. Recurrent Adaptive Neuro-Fuzzy Inference System (RANFIS) is utilized in this paper in a new effective design to improve the performance of classical and adaptive Proportional Integral (PI) controllers applied for the PITCH control purposes. Adaptive-online performance and high robustness coverage are the main advantages of the suggested controller. The effectiveness of the proposed method is verified by a simplified two-mass wind turbine model and a detailed aero-elastic wind turbine simulator (FAST7). At any given wind speed, the proposed controller has outperformed PI, Adaptive Neuro-Fuzzy Inference System (ANFIS), and RANFIS based controllers, reducing the mechanical stress of drive train while presenting suitable aerodynamic power tracking and maintaining the rotational speed of the rotor under the rated value.

Due to growth of energy consumption and depletion of fossil fuels sources, power generation of renewable energy sources such as wind energy has become one of the main interests of researchers. Among different types of wind turbines used for extracting electric power from wind flow, vertical axis wind turbines can be implemented in urban areas and in proximity of energy consumers because of their independence of wind direction, low sensitivity to wind turbulence and lower noise production. In this paper a straight‐BLADEd vertical axis wind turbine has been simulated 3 dimensionally by use of a commercial CFD code. The numerical results have been validated against available experimental data. To improve the performance of the turbine, the effects of BLADE mount point offset and preset PITCH have been investigated. The results show that appropriate BLADE offset and preset PITCH leads to a 60 and 65 percent increase in the maximum performance coefficient respectively.

In recent years, because of need to energy production at low cost, using micro hydro turbines has been very attractive. The low construction costs, easy installation and maintenance, low head and flow requirements, small size, no need for the extensive power network and decentralization of hydro power are some of the unique characteristics of Micro hydro turbines. Hydrocoil turbine as a new, efficient and affordable axial flow turbine is one of the best options for distributed generation of electricity. Although Hydrocoil’ s design is mainly inspired by Archimedes screw turbine, there are differences in their BLADE’ s PITCH and installing ANGLE. In this work, two different samples of hydrocoil turbine with constant and variable PITCHes have been studied numerically under identical conditions to study the effect of PITCH changes on operating point at constant head and five different rotational speeds. The results indicate that efficiency and power of variable PITCH turbine are 30 to 40 percent more than constant PITCH turbine. These results provide necessary background to build optimized variable PITCH hydrocoil for the first time in Iran.