Self-starting Capability Research Articles

Study on a novel dual-row vertical axis wind turbine with J-Shaped blades by using numerical methods and optimization

ABSTRACT This study investigates the benefits of using J-shaped blades in a dual-row Darrieus wind turbine (DDWT), combining two innovative ideas whose simultaneous impact on the self-starting capability of Darrieus turbines has not been explored. The performance of the turbine was simulated using Computational Fluid Dynamics (CFD) and optimized using both the Taguchi method and a combined Machine Learning and Genetic Algorithm (ML-GA) technique. Three main operating parameters, including the tip speed ratio (λ), radial ratio (δ), and angular distance (ϕ) of dual-row turbines, were investigated across four levels using an L25 orthogonal array design. According to the Taguchi analysis, the impact of the parameters on the power output was ranked in the order of λ > δ > ϕ. After comparison, the optimized turbine predicted by the ML-GA technique was chosen due to the superior accuracy of the ML-GA approach compared to the Taguchi method. The optimal configuration of a DDWT with J-shaped blades was predicted at λ = 2.15, δ = 1.39, and ϕ = 75.36, with a Cp of 0.49 based on CFD simulations. Compared to the single-row wind turbine, the proposed turbine showed a significant increase of the Cp at low tip speed ratios resulting in a better self-starting performance.

Numerical and experimental investigation of Darrieus vertical axis wind turbines to enhance self-starting at low wind speeds

Wind energy, being renewable, cost-effective, and environmentally friendly, has attracted global attention. However, due to suboptimal performance and limited research, vertical axis wind turbines (VAWTs) lag behind horizontal axis wind turbines (HAWTs) in commercial applications, particularly for large-scale installations. This study aims to improve the self-starting capability of the Darrieus VAWT. While some parameters, such as the number of blades (N) and solidity (σ), have been studied extensively, the airfoil shape has not received as much attention. This study compares the performance of National Advisory Committee for Aeronautics (NACA) airfoils and Selig airfoils at a Reynolds number (Re) of 40,673. The investigation revealed that the NACA0015 airfoil exhibited the highest peak power coefficient (Cp). Further analysis utilizing an advanced double multiple stream tube (DMST) code in MATLAB increased the peak Cp by adjusting the thickness-to-camber ratio (t/c) of the NACA0015 airfoil, resulting in a 12.50 % increase in the maximum achievable Cpat a Re of 40,673. This study compared four modes of VAWT operation, utilizing the NACA0015 airfoil and a modified NACA0015 airfoil for both straight-bladed and embossed-bladed VAWTs. The results showed that the modified NACA0015 airfoil for embossed-bladed VAWTs exhibited the best self-starting capability and rotation at wind velocities of 1 to 9 m s-1. Additionally, the self-starting force required by embossed-bladed VAWTs was lower than that needed by straight-bladed VAWTs due to the ability of the embossed material to enhance airflow attachment to the VAWT and suppress turbulence.

A Study on the Effect of Turbulence Intensity on Dual Vertical-Axis Wind Turbine Aerodynamic Performance

Examining dual vertical-axis wind turbines (VAWTs) across various turbulence scenarios is crucial for advancing the efficiency of urban energy generation and promoting sustainable development. This study introduces a novel approach by employing two-dimensional numerical analysis through computational fluid dynamics (CFD) software to investigate the performance of VAWTs under varying turbulence intensity conditions, a topic that has been relatively unexplored in existing research. The analysis focuses on the self-starting capabilities and the effective utilization of wind energy, which are key factors in urban wind turbine deployment. The results reveal that while the impact of increased turbulence intensity on the self-starting performance of VAWTs is modest, there is a significant improvement in wind energy utilization within a specific turbulence range, leading to an average power increase of 1.41%. This phenomenon is attributed to the more complex flow field induced by heightened turbulence intensity, which delays the onset of dynamic stall through non-uniform aerodynamic excitation of the blade boundary layer. Additionally, the inherent interaction among VAWTs contributes to enhanced turbine output power. However, this study also highlights the trade-off between increased power and the potential for significant fatigue issues in the turbine rotor. These findings provide new insights into the optimal deployment of VAWTs in urban environments, offering practical recommendations for maximizing energy efficiency while mitigating fatigue-related risks.

Numerical analysis of the impact of helical-blade design on flow characteristics and energy utilization in vertical-axis water turbine

In this study, a vertical-axis helical-blade water turbine is innovatively proposed by drawing on the design scheme of the traditional straight-blade turbine, compared to which this blade form can effectively improve the self-starting capability and energy capture efficiency of the turbine. The study analyzes the hydrodynamic performance of the device under different parameters using CFD (computational fluid dynamics) software STAR-CCM+ and overlapping mesh technique, and the CFD simulation results are verified with published experimental work. First, the design concept of the hydraulic turbine is presented, focusing on the design of the blades and transmission mechanism to ensure the stability of the structure. Second, the effect of two-dimensional parameters on the flow field characteristics and efficiency is investigated, and then three-dimensional design parameters, such as blade helix angle and hub-to-tip ratio, are considered. The results show that a 20% increase in blade density results in a 10.74% increase in efficiency. Regarding flow velocity, a maximum output of 2.4 kW was achieved for four operating conditions (1.0, 1.5, 2.0, and 2.5 m/s). In addition, the average dynamic torque of the helical-blade turbine was 16.44% higher than that of the straight-blade turbine, indicating superior self-starting capability. It was also found that at an aspect ratio of 1.5–1.75 and a helix angle of 80°, the energy capture efficiency of the helical-blade turbine was 33.7%, which was 45.3% higher than that of the straight-blade turbine. Comparative analysis shows that the vertical-axis helical-blade turbine has favorable hydrodynamic performance, especially under low flow conditions, and the design scheme shows obvious advantages, which makes up for the defects of the traditional vertical-axis straight-blade turbine with poor self-starting ability and low efficiency, and fills up the research gaps of vertical-axis turbine design optimization, which is of certain research value.

Bioinspired swept-curved blade design for performance enhancement of Darrieus wind turbine

The present research proposes novel swept-curved bioinspired blades for Darrieus wind turbine. The design was influenced by the curved flippers of the bottle-nose dolphin. The proposed model was designed using the Solidworks software, empirically tested for power improvement, later fine-tuned adopting high fidelity numerical modeling. An in-depth analysis comparing the traditional H-bladed turbine with the new-bladed design was performed using OpenFOAM. Further, an elaborate experimental observations on the proposed design suggest that the model with 0.6c forward sweep outperformed the rest. The efficiency of the curved blade was notably enhanced by 14.41%, in contrast to the conventional model, and the numerical analysis endorses this observation. The modified turbine blades have the maximum wind streamlines that converge toward the center of the blade's trailing edge due to the lateral shift, and the resulting convergence reduces blade tip losses. The modified blade models demonstrated improved angular acceleration at a given wind speed, indicating enhanced efficiency and superior self-starting capabilities. Notably, these improvements were evident even at a lower wind speed of 4.2 m/s compared to the traditional H-model.

Effects of the influence of triangular dimple and aspect ratio on NACA 4412 airfoil on the overall performance of H-Darrieus wind rotor: An experimental investigation

This study examines how adjusting aspect ratio (AR) and adding triangular dimples to the airfoil can enhance H-type Darrieus wind rotor (H-rotor) performance under low wind speeds (4, 6, and 8 m/s) using wind tunnel testing. Results show optimal performance at an AR of 1.0 for both standard and Triangular dimple airfoil H-rotors, with variations at different wind speeds for other aspect ratios. Triangular dimple-equipped H-rotors demonstrate improved self-starting capability and a wider operational range of tip speed ratio (TSR) compared to standard rotors, ensuring reliability across diverse wind conditions. Moreover, the triangular dimple rotor achieves a nearly 13.6% increase in maximum coefficient of power ([Formula: see text]) compared to the dimple-free H-rotor at 4 m/s wind speed. This study underscores the efficacy of adjusting AR and integrating triangular dimple blades to enhance H-rotor performance, particularly in low wind speeds.

Commercial Small-Scale Horizontal and Vertical Wind Turbines: A Comprehensive Review of Geometry, Materials, Costs and Performance

The effective exploitation of renewable energy sources is one of the most effective solutions to counter the energy, environmental and economic problems associated with the use of fossil fuels. Small-scale wind turbines (converting wind energy into electric energy with a power output lower than 50 kW) have received tremendous attention over the past few decades thanks to their reduced environmental impact, high efficiency, low maintenance cost, high reliability, wide wind operation range, self-starting capability at low wind speed, limited installation space, reduced dependence on grid-connected power and long transmission lines, low capital costs, as well as the possibility to be installed in some urban settings. However, there are significant challenges and drawbacks associated with this technology from many different perspectives, including the significant discrepancy between theoretical performance data provided by the manufacturers and real field operation, that need to be investigated in greater depth in order to enable a more widespread deployment of small-scale wind turbines. In this review, a complete and updated list of more than 200 commercially available small-scale horizontal and vertical wind turbine models is provided and analysed, detailing the corresponding characteristics in terms of the number and material of blades, start-up wind speed, cut-in wind speed, cut-out wind speed, survival wind speed, maximum power, noise level, rotor diameter, turbine length, tower height, and specific capital cost. In addition, several scientific papers focusing on the experimental assessment of field performance of commercially available small-scale horizontal and vertical wind turbines have been reviewed and the corresponding measured data have been compared with the rated performance derived from the manufacturers’ datasheets in order to underline the discrepancies. This review represents an opportunity for the scientific community to have a clear and up-to-date picture of small-scale horizontal as well as vertical wind turbines on the market today, with a precise summary of their geometric, performance, and economic characteristics, which can enable a more accurate and informed choice of the wind turbine to be used depending on the application. It also describes the differences between theoretical and in-situ performance, emphasizing the need for further experimental research and highlighting the direction in which future studies should be directed for more efficient design and use of building-integrated small-scale wind turbines.

Exploring the impact of flexible membranes on the performance of H- and S-type hydrokinetic turbines: An experimental investigation

Vertical axis hydrokinetic turbines (VAHTs) have the potential to harness deep-sea current energy without the need for a yaw mechanism. However, H-VAHTs have weak self-starting capabilities, and S-VAHTs also face startup dead point issues. To address the self-starting challenges of VAHTs, this study proposes attaching flexible membranes to the blades of VAHTs. The impact of flexible membranes on the performance of both types of VAHTs is evaluated through Particle Image Velocimetry (PIV) water flume experiments. The results demonstrate that attaching flexible membranes to the blade surfaces resolves the self-starting dead point issue for both turbines, with a greater improvement in self-starting performance for H-VAHTs than for S-VAHTs. The study found that for both turbines, attaching flexible membranes with a large opening on the blade’s outer side offers the best self-starting performance and power output. However, the flexible membranes reduced the CP of H-VAHTs, while slightly enhancing the performance of S-VAHTs. PIV tests showed that the flexible membranes form a cup-shaped structure when facing the flow. The pressure difference between the inside and outside of the membranes generates additional static torque, improving the self-starting performance of both turbines. Furthermore, even with one or two membrane blades missing, the self-starting capability of H-VAHTs was still enhanced; flexible membranes with a certain installation angle can also be attached to the endplates of S-VAHTs to address startup dead issues. In summary, attaching flexible membranes to VAHTs improves their self-starting performance and ensures power output, thereby facilitating the application of such turbines in deep-sea areas with low flow velocities.

Development of a Predictive Model for Evaluation of the Influence of Various Parameters on the Performance of an Oscillating Water Column Device.

Oscillating Water Column (OWC) systems harness wave energy using a partially submerged chamber with an underwater opening. The Savonius turbine, a vertical-axis wind turbine, is well-suited for this purpose due to its efficiency at low speeds and self-starting capability, making it an ideal power take-off (PTO) mechanism in OWC systems. This study tested an OWC device with a Savonius turbine in an air duct to evaluate its performance under varying flow directions and loads. An innovative aspect was assessing the influence of power augmenters (PAs) positioned upstream and downstream of the turbine. The experimental setup included load cells, Pitot tubes, differential pressure sensors and rotational speed sensors. Data obtained were used to calculate pressure differentials across the turbine and torque. The primary goal of using PA is to increase the CP-λ curve area without modifying the turbine geometry, potentially enabling interventions on existing turbines without rotor dismantling. Additionally, another novelty is the implementation of a regression Machine-Learning algorithm based on decision trees to analyze the influence of various features on predicting pressure differences, thereby broadening the scope for further testing beyond physical experimentation.

A comprehensive investigation on Darrieus vertical axis wind turbine performance and self-starting capability improvement by implementing a novel semi-directional airfoil guide vane and rotor solidity

Darrieus vertical axis wind turbine is classified as a lift-based power generation turbomachine. However, it is burdened with the limitations of mid-range efficiency and requiring initial torque for startup. The quest to improve the turbine's performance has focused on enhancing its aerodynamic performance and self-starting ability. One of the most effective approaches is to flow control and injection toward the rotor blades. This computational fluid dynamics research study utilizes a novel geometry known as the “Semi-Directional Airfoil Guide Vane” (SDAGV) to inject airflow smoothly and effectively toward the rotor blades at the upstream section. The investigation found that using a two-passage SDAGV increased rotor efficiency by up to 55% at a tip speed ratio (TSR) of 2.5. The pressure distribution analysis showed that azimuth angles between 90° and 135° significantly impacted the rotor's self-starting ability. Additionally, studying the turbine solidity revealed that a five-bladed rotor with SDAGV had a higher self-starting capability and efficiency than a two-bladed rotor with SDAGV. This was because its power coefficient (Cp) was approximately 160% greater at TSR = 1.4. Due to blade-to-blade interaction, high-solidity turbines from TSR = 2 onwards face performance challenges, which means their efficiency drops in the low-TSR range.

Experimental Test Bench In A Wave Flume For The Development Of A New Mini Morphable Wells Turbine

The aim of this research study is to perform experimental tests on a new morphable mini Wells turbine designed to operate in presence of waves with limited energy content which presents a high frequency of occurrence along the Mediterranean coasts (Corsini et al., 2010). The strengths of these mini Wells turbines are: i) extremely light rotor; ii) no need of actuators to morph the rotor blades; iii) low construction and maintenance costs; iv) capability to produce energy starting from low wave heights in the order of a few decimetres. Furthermore, the small size and low investment costs of the turbine make it particularly suitable to be installed either in existing structures, such as anti-reflective perforated caissons (often used in the Mediterranean harbors), or in devices for coastal defense from erosive phenomena located on shallow water conditions. The need to carry out experimental tests derives from the difficulty of handling in a virtual Computational Fluid Dynamics environment the huge difference in the time scale of the turbine, which spins at 1500-3000 rpm, and the wave periods, in the order of some seconds (Corsini et al., 2012; Barnabei et al., 2020). Properly designed lab tests, executed in controlled conditions with irregular sea states, are therefore mandatory to fully characterize the behavior of morphable Wells turbines to be employed in the Mediterranean Sea, and in particular to assess their self-start capability.

Mode-locked large-mode-area Er/Yb-doped fiber oscillator via nonlinear polarization evolution with enhanced mode suppression

We report a mode-locked Er/Yb-doped large-mode-area (LMA) fiber oscillator based on nonlinear polarization evolution (NPE), which utilizes a linear cavity primarily composed of polarization-maintaining (PM) fibers. The oscillator operates at 1.56 µm with a fundamental repetition rate of 34.47 MHz and has two output ports. One port can deliver high-quality soliton-like pulses with a pulse duration of 325 fs and an average power of 39.5 mW (corresponding to a pulse energy of 1.15 nJ). In contrast, the other port not only generates lower-quality complex pulses but also exhibits poorer short-term and long-term stability, likely due to cross-phase modulation effects. To the best of our knowledge, this is the first implementation of the NPE mode-locked technology in a PM-LMA Er/Yb-doped fiber oscillator at 1.55 µm which often suffers from poor self-starting mode-locking capabilities. This achievement is primarily attributed to the use of endlessly single-mode photonic crystal fibers, which effectively suppress higher-order modes in PM-LMA fibers.

Experimental Study on the Effect of Foil Guide Vane on the Performance of a Straight-Blade Vertical Axis Ocean Current Turbine

Indonesia is a country that has enormous energy potential for ocean currents, but the speed of ocean currents is relatively low. The straight-blade vertical axis ocean current turbines can be used to generate electricity. However, one of the disadvantages is lower performance compared to horizontal axis turbines. This study aims to improve the performance of straight-blade vertical axis ocean current turbines using a foil guide vane (FGV). Experimental studies have been conducted in a water tunnel at the Energy Systems Engineering Laboratory, Institut Teknologi Sumatera (ITERA), South Lampung, Indonesia. The investigation is carried out in two stages: the straight-blade without FGV as the original object; the straight-blade with FGV as a variation to improve the turbine performance. The investigation results show that the FGV can enhance the performance of straight-blade vertical axis ocean current turbines such as self-starting, torque coefficient (C_t), and power coefficient (C_p). The FGV has increased self-starting capability at a minimum current speed of 0.078 m/s by 15.3 rpm. The increase in maximum torque coefficient (C_t max) and power coefficient (C_p max) due to the FGV is 32% and 20%, respectively, with a C_t max of 0.829 and 〖a C〗_p max of 0.519. In addition, an investigation was also carried out on flow visualization. It showed that FGV could absorb a lot of injection ink, which means that the turbine with FGV absorbs more kinetic energy than without FGV.

Wind tunnel tests of a two-bladed Savonius wind rotor with novel parabolic blades

The study presents an experimental research on a vertical-axis Savonius wind rotor featuring optimized parabolic blades. This parabolic blade is developed by optimizing its sectional cut-angle through a series of numerical simulation. The parabolic-bladed Savonius rotor of various aspect ratios is tested in a low-speed wind tunnel to evaluate its power coefficient ( CP) along with its self-starting capability. For a direct comparison, the tests are also conducted for a rotor with the semicircular blades. The wind tunnel tests demonstrate the peak CP of the parabolic and conventional semicircular bladed rotors to be 0.165 and 0.138, respectively at a tip-speed ratio of 0.67 and an aspect ratio of 0.9. The wind rotor with the parabolic blades shows an improvement of CP by 19.56% against its conventional semicircular counterpart. With the inclusion of blockage correction, the test rotors with parabolic and semicircular blades show the CP of 0.161 and 0.134, respectively.

Advances and opportunities in wind energy harvesting using plasma actuators: a review

Abstract The dielectric barrier discharge plasma actuator has been recognized as a leading technology for controlling fluid flow and has found remarkable applications in wind energy harvesting over the past decade. Wind turbine aerodynamics are critical in this concept and performance is mainly determined by flow controllers, although significant technical progress is still required. This paper examines all the critical studies to investigate the potential application of plasma actuators for airflow control over wind turbines. This approach has been divided into three categories: wind turbine airfoils, horizontal-axis wind turbines and vertical-axis wind turbines aerodynamic performance and generated power. Finally, the potential functions of plasma actuators in current and future wind turbine generators are discussed. These actuators offer promising solutions to increasing power output, minimizing torque fluctuations and enabling self-starting capabilities, particularly in vertical-axis wind turbines. By adjusting blade pitch angles in conjunction with plasma actuators, significant improvements in airflow optimization and power extraction have been demonstrated. Despite the advancements, challenges persist, such as determining optimal actuator placement and overcoming structural limitations, especially concerning 3D effects and high Reynolds numbers. While plasma actuators enhance aerodynamic efficiency, their complexity needs to be balanced against marginal gains in power production, especially in high-megawatt turbines, for which controlling flow at low wind speeds is challenging. Future research must focus on the sustainable integration of plasma actuators, pitch angle adjustments and active control mechanisms to fully exploit the potential of wind energy for a sustainable future.

Performance of Savonius Wind Turbine Affected by Circular Cylinder Beside Advancing and in front of Returning Blade: Experimental Method

This study investigates the influence of circular cylinders positioned beside the advancing blade and in front of the returning blade on the performance of a Savonius wind turbine. The experimental method focuses on assessing how these cylinders affect the turbine’s efficiency and self-starting capability. Various distances between the cylinders and the turbine blades (S/D = 1.4) and different cylinder positions (Y/D = 1.27, 1.32, 1.37, 1.42, 1.51, 1.61, 1.71, 1.82, 2.00) were explored. Tests were conducted under constant speeds corresponding to Reynolds numbers of Re = 120,000 and 150,000. Preliminary findings of all various distances indicate a significant improvement in turbine performance, particularly in enhancing self-starting ability, when using these disturbance cylinders compared to conventional designs. Specifically, the configuration with cylinders positioned at S/D = 1.4 and Y/D = 1.51 demonstrated the most promising results, showing the static torque coefficient a 48% increase in performance at a wind speed of 6 m/s and a remarkable 78% increase at 7 m/s. These results highlight the potential of utilizing circular cylinders strategically around Savonius wind turbines to optimize their performance and operational efficiency.

A numerical study on the blade–vortex interaction of a two-dimensional Darrieus–Savonius combined vertical axis wind turbine

To investigate power losses of a Darrieus–Savonius combined vertical axis wind turbine (hybrid VAWT) associated with the interaction between blades and wake, it is crucial to understand the flow phenomena around the turbine. This study presents a two-dimensional numerical analysis of vortex dynamics for a hybrid VAWT. The integration of a Savonius rotor in the hybrid VAWT improves self-starting capability but introduces vortices that cause transient load fluctuations on the Darrieus blades. This study attempts to characterize the flow features around the hybrid VAWT and correlate them with the Darrieus blade force variation in one revolution. Results demonstrate the capability of numerical modeling in handling a wide range of operational conditions: the relevant position of Savonius and Darrieus blades (attachment angle γ=0°−90°) and Savonius' tip speed ratio λS (0.2–0.8, varied Savonius' rotational speed). The torque increase in the Darrieus blade in hybrid VAWT (compared to a single Darrieus rotor) due to the appearance of the vortex shedding from the advanced Savonius blade is independent of the attachment angle and tip speed ratio. Apart from start-up and power performances of the hybrid VAWT, the most rapid force fluctuation is identified when the Darrieus blade interacts with Savonius' wake at γ=0° and λS=0.8, which is considered undesirable. Furthermore, attachment angles of 60° and 90° exhibit better power coefficients compared to those of 0° and 30° for the hybrid VAWT. This study contributes to a comprehensive understanding of flow dynamics in hybrid VAWTs, revealing the correlation between torque variation and vortex development.

Starting Characteristics of Curved Compression Ramp Air Intakes with Overboard Spillage

An analytical framework is presented here for estimating the limiting area contraction for a family of curved compression ramp (CCR) supersonic air intakes with self-starting capability via overboard spillage. Flow compression in CCR intakes occurs through a combination of a curved ramp shock wave and a series of compression waves. In general, such a combination offers the best features of the canonical air intake families. That is, pressure recovery in CCR intakes is better than simple ramp (planar ramp) air intakes, and pressure ratios in CCR intakes are better than Prandtl–Mayer air intakes. A modified Kantrowitz criterion for startability is proposed to accommodate the nonuniform Mach number distribution in the cross-stream direction at the intake throat that is inevitably realized in CCR air intakes. The starting characteristics of different design configurations that fall within the family of CCR air intakes are analyzed, and a comparison is made with planar ramp and Prandtl–Meyer intakes. Inviscid flow numerical experiments of intake starting were carried out to successfully verify the starting characteristics predicted by the analytical model. The analytical framework presented here can be employed as a general tool for optimizing air intake design based on startability, efficiency, and other performance considerations.

Influences of Yaw characteristics on the performance of an Archimedes screw hydrokinetic turbine

A system for in situ power generation that exploits deep-sea current energy has been developed to meet the electricity demands of deep-sea observational equipment. The Archimedes screw hydrokinetic turbine (ASHT) is notable for its self-starting capabilities and energy efficiency, making it well suited for deployment in the low-speed deep-sea environment. This study elucidates two distinctive hydrodynamic characteristics of ASHT and explicates the underlying operational principles for the first time. Specifically, the ASHT is capable of self-yawing without the need for auxiliary yawing mechanisms and, when fixed, can harness ocean currents from a wide array of directions. Based on these hydrodynamic characteristics, passive yaw and fixed installation methods are proposed. A rigorously validated numerical model, supported by water flume tests, is utilized to illuminate the real-time flow mechanisms and assess the effect of different geometric variables on the ASHT yawing performance. An in-house Simulink model evaluates the power supply capabilities of both installation options, revealing that fixed installations are preferable for locations with varied incoming flow angles, whereas passive yaw installations are more appropriate for sites with a restricted range of incoming flow angles.

Performance Study of a Humpback Whale Fluke Turbine on Foil Shape Variation Based on Double Multiple Streamtube Model

Exploration of ocean current energy allows for the development of turbines as the primary conversion device. Turbine technologies have been developed in various types, including bio-inspired turbines, such as the humpback whale fluke turbine. In this study, the achievement of a humpback whale fluke turbine is investigated by applying various forms of foil, both symmetric and asymmetric, to obtain the appropriate foil profile. Symmetric foils were represented by NACA 0012, NACA 0018, and NACA 0021, while asymmetric foils were represented by NACA 4312, NACA 4512, and NACA 4712 foils. Simulations were performed using QBlade software, which was developed based on the DMST theory. In general, symmetric foils have a more stable performance than asymmetric foils because they produce a better performance at positive and negative angles of attack. This result is also supported by a review of efficiency and self-starting capability where symmetric foils have significantly higher CP values and positive CQ along the azimuth angle than asymmetric foils. Finally, NACA 0021 foil is recommended for a humpback whale fluke turbine based on its efficiency and self-starting capability.