Vane Turbine Research Articles

Performance Analysis of an Air Turbine for Ocean Energy Extraction Using CFD Technique

The oscillating water column, which has a pneumatic section, can convert wave energy to air pressure, and thus, it rotates the turbine. The system has an inherent weakness of having low efficiency. Typically, the small Wells or axial turbines without any modifications have an efficiency of less than 40% under good sea wave condition which is a drawback and considered as less efficient to extract energy from the oceans. In this paper, the performance of the turbine is studied and analyzed by a computational fluid dynamics technique. ANSYS commercial code is used to discretize the mass, momentum, energy equations, and the turbine efficiency was evaluated. Different guide vane angles and turbine diameters were considered for the simulations. The modified turbines are simulated to operate in various rotational speeds which are similar to an actual working of oscillating water column. This helps to find a suitable operational range for the proposed turbine for energy extraction. It was found that the bigger turbines are expected to produce relatively higher efficiencies at lower speeds and lower pressures.

Effect of Tip Configurations on Aerodynamic Performance of Variable Geometry Linear Turbine Cascade

Abstract The variable geometry turbine (VGT) has been widely used in different fields due to its higher efficiency and lower fuel consumption at part-load. However, the flow field in a VGT is characterized by the leakage flow through the radial clearance of rotational vane compared with a general fixed vane turbine. Numerical simulations are conducted on a linear turbine cascade to reduce the leakage flow based on passive control method. The aerodynamic performances and flow fields are compared for four kinds of tip configuration firstly. Then, the effect of variable geometry on the linear turbine cascade aerodynamic performance is investigated for five installation angles ranging from –5 to 5 deg. In addition, the development patterns and trends of the tip leakage vortex and the passage vortex are analyzed. The results show that the squealer tip and the rotating axis have a significant impact on suppressing leakage flow. The leakage flow rate has a tendency to decrease, and the total pressure coefficient is gradually increased when installation angle ranges from –5 to 5 deg. The interactions between tip leakage vortex and passage vortex leads to the different trends on leakage flow at various installation angles and axial sections.

Novel Design of Vertical Axis Current Turbine for Low Current Speed via Finite Volume Method

Now a day, increasing energy demand and environmental effect of fossil fuel cause to replacing fossil fuel with renewable energy. This paper presented novel design of turbine to generate more torque to capture more energy of water and hence cause to high output power. In this work Computational Fluid Dynamics (CFD) using realize k-e turbulence model, have been used to analyses the effect of arm on the static torque and the contours of pressure in different angle of direction for vertical vane turbine. Investigation of arm effect on static torque of vertical vane turbine and comparison between turbine with arm and without arm showed the average torque in vertical vane turbine is higher than without arm. The model settings of validation study was accomplished by comparing simulation of performance of turbine Cp and Cm with the experimental data taken from Hayashi and Hara (2005),that showed realize k-e has good agreement with experimental data.

Development of the construction of a gas turbine engine vane with built-in vortex tubes

This paper presents the results of numerical and experimental studies of heat transfer of swirling flows in channels and cyclonic vortex tubes using as a working medium of air and superheated steam. The research results of the calculation depends on the number of elements of the computational domain and on the time step. The experimental data were compared non-adiabatic of the vortex tube in air and water vapor. Numerical study of conjugate heat transfer vane turbine with two integrated eddy energy separators with superheated steam as a coolant. Given flow characteristic of the blade, the dependence of the cooling efficiency of the coolant flow and temperature distribution obtained in the material of the blade.

Minimizing Axial Energy Loss by Using Vane Turbine in the Propeller Slipstream

The paper describes the results of analytical investigation on the application of vane-turbine in the propeller slipstream. The vane-turbine is attached on single-and twin-screw ships with total number of investigated ships are 20. Performance of the turbine was analyzed by actuator disc method. The effect of vane-turbine on ship performance is investigated. Discussions are focused on two main topics, namely speed loss and power efficiency gain. Final result finds out that the ratio of the thrust-power producing by vane turbine and thrust-power producing by propeller will influence the efficiency gain.

Vane-Turbine as an Energy Conversion in the Propeller Slipstream of Single Screw Ship

The screw propeller of a ship generates thrust to make it moving. As a propeller rotates, it draws fluid into itself from the surrounding area (slipstream). The propeller produces two types of flow behind it, accelerated and circulated flows. Some of the energy from the ship engine is lost in the accelerated flow behind ship as a jet wash.The kinetic energy losses in the slipstream propeller captured by a turbine called the propeller-turbine system. This composed screw propeller of a vessel (the main propeller) and a vane turbine that is the area of vanes located inside the wake of the main propeller. It recovers the energy generated by the main propeller pushing water back out (which would be otherwise wasted behind the main propeller) and hopefully enhancing the efficiency of the main propeller.The influence of vane turbine on the performance breakdown of single screw ships were analyzed by using 5 (five) ships . Ship powering was calculated by using DESP Code 10 software. Thrust and power of vane turbine were calculated by applying actuator disc theory. Although the vane turbine affected speed loss of the ship, the power efficiency gained to be found always positive. Vane turbine is suitable as an energy saving device of the single screw ship.

Power augmentation effects of horizontal axis wind turbine by tip vane. 1st report. Relationships between turbine performance and configuration of tip vanes.

Output of horizontal axis wind turbine is improved by tip vane. The maximum improved value of tip vane turbine is 1.25 times larger than non-tip vane turbine output. The paper describes the relationships between turbine performance and configuration of tip vanes. Many tip vanes were used to improved the performance. It is found that V and S type tip vanes are vesy useful to improve the performance. Also, dimensions of V and S type vanes were investigated in details.

Rotor dynamics of a sliding vane turbine

A general mechanical design and performance analysis is presented for a sliding vane turbine. The analysis is general in the sense that it is valid for any stator profile and that there is no restriction on the turbine use. This analysis includes a dynamic force analysis on the vane, rotor dynamics, and vane kinematics. As an example, an eliptical stator sliding vane turbine is considered for the purpose of illustrating the procedure of applying the general analysis and presenting results by graphs as a function of significant design parameters.