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Introduction
Prof. Abdus Samad works in the area of Marine Energy and Fluid Machinery at IIT Madras. The ocean Wave Energy harvesting systems faced challenges of low power output, and he introduced new turbine-blade design concepts. Subsequently, he and his team received several awards. He published more than 150 articles. He was elected as a fellow of ASME, IEI and IMechE. He executed/ is executing several international research projects (India-Korea, India-UK, India-Germany and India-USA).
Skills and Expertise
Current institution
Additional affiliations
March 2020 - May 2020
August 2015 - March 2020
September 2004 - August 2008
Education
September 2004 - August 2008
Publications
Publications (226)
The life cycle assessment (LCA) is an inevitable part of ocean wave energy systems. This paper presents an LCA of the Sindhuja-I ocean wave energy converter (WEC). The WEC is a point absorber type WEC tested at the Tuticorin port in India. This study utilized the ISO 14044 standard and SimaPro LCA software to assess the environmental impact of the...
Wave energy converters (WECs) behave differently when operating in irregular waves than regular ones. Although numerous studies describe WEC dynamics in regular waves, the ocean experiences irregular waves, making it essential to evaluate performance under such conditions. A multibody WEC has mixed motion, adding complexity to the system dynamics....
![Potential Capacity of Ocean Energy [12] Ocean Energy and Its Potential](profile/Kalyan_Chakravarthi_T_V_S2/publication/387206561/figure/tbl1/AS:11431281305464396@1737790986637/Potential-Capacity-of-Ocean-Energy-12-Ocean-Energy-and-Its-Potential_Q320.jpg)
A point absorber (PA) is one of the commercially produced wave energy converters (WECs) globally, owing to its small size compared to larger wavefronts and ease of design. A narrow-banded system works best when it resonates with the surrounding waves. However, the high frequency of such a system makes it difficult to gain maximum power output. Thus...
The study aims to assess the feasibility of harnessing wave energy from the low‐energy waves prevalent along the east coast of India, where wave energy converters (WECs) may not produce sufficient power economically. Vishakhapatnam port, located on the east coast, experiences such waves (period, Tp = 5 to 10 s, and wave height, Hs = 0.07 to 2.61 m)...
India can harness 40 GW of ocean energy from its 7500 km long coast. There are several devices to harness such power. One commonly researched device is an oscillating water column (OWC). One end of the duct faces the water, while the other is open to the atmosphere. When the wave enters the duct, the air is pushed out; when the wave recedes, the ai...
Separated flow on a Wells turbine blade causes poor performance of the turbine. Implementing passive flow control techniques, such as leading-edge prism cylinders (LE-PCs), effectively delays flow separation within a system. The prism cylinder alters the angle of attack (AoA) and modifies the boundary layer profile. The shapes of the prism cylinder...
COVID-19 is an airborne disease, with the vast majority of infections occurring indoors. In comparison, little transmission occurs outdoors. Here, we investigate the airborne transmission pathways that differentiate the indoors from outdoors and conclude that profound differences exist, which help to explain why SARS-CoV-2 transmission is much more...
Covid-19 is an airborne disease, with the vast majority of infections occurring indoors. By comparison, little transmission occurs outdoors. Here, we investigate the airborne transmission pathways that differentiate the indoors from outdoors, and conclude that profound differences exist, which help to explain why SARS-CoV-2 transmission is much mor...
A major challenge of ocean wave energy converter (WEC) development is to test in the actual ocean. In this article, how a point absorber (PA) WEC was developed and tested during the mid of November 2022 in the ocean is reported. The WEC named Sindhuja-1 was developed from concept, numerical modelling, and laboratory testing. The test site was the V...
In response to the need for efficient, small-scale power sources for applications such as ocean observation and navigation, this paper presents the design, modeling, fabrication, testing, and analysis of a compact point-absorber wave energy converter (PAWEC) equipped with a mechanical direct-drive power takeoff (PTO) mechanism. The motivation is to...
![Fig. 1. Schematic of an OWC with UTs (turbine-duo) [3]](profile/Emeel-Kerikous/publication/373628790/figure/fig1/AS:11431281195147277@1696341270998/Schematic-of-an-OWC-with-UTs-turbine-duo-3_Q320.jpg)
![Fig. 2. Working principle of nozzle type diode [10]](profile/Emeel-Kerikous/publication/373628790/figure/fig2/AS:11431281195147278@1696341271221/Working-principle-of-nozzle-type-diode-10_Q320.jpg)
The oscillating water column (OWC) is an extensively studied wave energy converter that produces pneumatic power from the motion of the sea waves, which can be harvested using a pair of turbines without additional devices. However, its efficiency is hampered by poor flow blockage. Researchers have proposed a fluidic diode (FD) to improve flow block...
Unsteady Reynolds-Averaged Navier–Stokes (URANS) and SST-based improved delayed detached eddy simulation (SST-IDDES) are used to compare the performance, flow field characteristics, and downstream turbine installation distance of a Marine Current Turbine (MCT). The flow domain is discretized with unstructured tetrahedral mesh using the Fluent 2020R...
This study extracts and reports notable findings on passive micromixers by conducting an exhaustive review of designs, their features, and mixing performance. The study has covered the relevant articles on passive micromixers published from 2010 to 2020. The analysis of filtered and selected articles sums up passive micromixers into four categories...
![Inactivation constants Z in aerosol [7].](publication/369586714/figure/tbl1/AS:11431281131115659@1680027133833/Inactivation-constants-Z-in-aerosol-7_Q320.jpg)
Existing indoor closed ultraviolet-C (UVC) air purifiers (UVC in a box) have faced technological challenges during the COVID-19 breakout, owing to demands of low energy consumption, high flow rates, and high kill rates at the same time. A new conceptual design of a novel UVC-LED (light-emitting diode) air purifier for a low-cost solution to mitigat...
Remarkable advancement in wave energy conversion technology has taken place in recent years. Due to its simplicity, the Wells turbine has been one of the most widely used power take-off mechanisms in an oscillating water column type wave-energy conversion device. However, the turbine suffers from several challenges due to its narrow operating range...
The present study attempts to enhance a Wells turbine performance by adopting a leading-edge microcylinder (LEM) as a passive flow control device. The microcylinder is placed near the blade leading edge so that its axis lies on the chord line of the rotor blade. The influence of turbine performance, due to parameters such as microcylinder diameter...
A pair of turbines can harness power from a wave energy Converter. Their performance is poor than individual turbines due to flow reversal. A fluidic diode (FD) which offers variable resistance to the flow, can be used to prevent flow reversal and improve the performance of these units. Its performance is given by diodicity (ratio of reverse to for...
![Inactivation constants Z in aerosol [7]](publication/363084941/figure/tbl1/AS:11431281081498448@1661829964961/Inactivation-constants-Z-in-aerosol-7_Q320.jpg)
A conceptual design of a novel UVC-LED air-cleaner is presented as part of an international educational-research study. The main components are a dust-filter assembly, a UVC chamber and a fan. The dust-filter aims to suppress dust accumulation that will hamper the UVC chamber operation. The innovation is in the UVC chamber that includes a novel tur...
Fillets on leading edges (LE) of turbine blades alter flow patterns and change the loss profile. A bidirectional flow impulse turbine utilized for harnessing wave energy is introduced and computational fluid dynamics (CFD) was used to perform various analysis. In the present work, fillets of different radii on the leading and trailing edges of both...
The present article reports optimization of the performance of a Wells turbine, which is an axial turbine utilized for wave energy conversion, through a computational fluid dynamics (CFD) based automated optimization technique. The in-house optimization library OPAL++ was coupled to a commercial CFD solver to get the Pareto front defining the relat...
The present work describes the design and analysis of a compact and modular wave-powered desalination (WPD) system. The design of the unit is influenced by the United States Department of Energy (DOE) Waves to Water competition rules. The system consists of a flap-type wave surge converter that converts wave energy into hydraulic piston force throu...
Remarkable advancement in wave energy conversion technology has taken place in recent years. Due to its simplicity, the Wells turbine has been one of the most widely used power take-off mechanisms in an oscillating water column type wave-energy conversion device. However, the turbine suffers from several challenges due to its narrow operating range...
Energy from the ocean is one of the least exploited renewable and sustainable energy sources, and possesses an enormous amount of untapped energy. The harnessing of energy from the ocean can be accomplished by several methods such as salinity and temperature gradient, waves, currents, and tidal variations. Amidst all, the ocean waves are a highly p...
Wave energy extracting devices such as an oscillating water column (OWC) in general have lower efficiency compared to other energy extracting techniques due to non-optimal design of various components. OWC is an empty vertical column housing an Wells or an impulse turbine. This chapter presents a detailed methodology in optimizing few design variab...
In a Wave Energy Converter (WEC), the Power Take-off (PTO) mechanism does the energy conversion through a series of mechanical and electrical systems. The PTO system plays a major role in defining the WEC system's structural dynamics. Since the PTO system directly affects the efficiency of power conversion, it has a significant role to play in the...
Wells turbine is an axial flow bi-directional turbine used for wave energy conversion by Oscillating Water Column (OWC) system. Different variations of Wells turbine have been studied and tested to find out the best rotor geometry. A comprehensive review of Wells turbine is presented here to familiarize the reader with the state of the art of Wells...
Optimization of wave energy converters (WECs) through robust controls is mandatory to maximize the energy absorption in the face of sea waves’ stochastic nature. Single optimization criterion predicted by linear models is rendered ambiguous when modulated by viscous forces, dominant at the controlled conditions. An efficient hydrodynamic model capa...
Winglets on a turbine blade can modify flow features and improve a marine current turbine (MCT). In this work, to maximize the power coefficient (CP) and torque (T), cant angle (α), and height (h) of a winglet of an MCT were modified. The problem was solved using a high-fidelity solver code Fluent 2019R2 containing Reynolds-Averaged Navier–Stokes (...
Oscillating water column (OWC) wave energy converters employ air turbines coupled with an electrical generator to convert the wave energy into electrical energy. In the present study, a ring-type axial flow impulse turbine of diameter 196 mm was manufactured to carry out the experiments in an unsteady flow test rig. The tests were done for the stro...
The power take off device used in Oscillating Water Column (OWC) type wave energy converters is mainly a bidirectional turbine: either an impulse turbine or a reaction (Wells) turbine. Both these turbines have been studied numerically and experimentally to understand the influence of different parameters. However, an experimental analysis is more r...
Wells turbine is a self-rectifying axial flow reaction turbine used to harvest energy from the ocean waves. It suffers from a premature stall at higher flow rates. The present study discusses a comparative performance analysis with a turbine-blade leading-edge (LE) microcylinder (LEM) and D-cylinder (LED). The space between the LE and the cylinder...
The performance enhancement of air turbines used in wave energy extraction is quintessential to realize the commercialization of wave energy plants.
This chapter discusses the various passive flow control methods used to enhance
the performance of the Wells and axial impulse air turbines that are employed in the
oscillating water column to harvest...
Blade leaning works well for steam, hydro and gas turbines, where the flow is unidirectional. In contrary, the turbine used in an oscillating water column wave energy device has a unique design which can work only in bidirectional flow and gives a unidirectional torque. In this article, a compound leaning concept is explored through numerical model...
An oscillating water column (OWC) wave energy device can use a bidirectional flow impulse turbine for energy extraction. The airflow velocity profiles during inhalation and exhalation of the OWC are asymmetric, and the flowrate at exhalation is higher. Hence, this article presents an optimized turbine to work for asymmetrical airflow conditions. Th...
The narrow operating range of a Wells turbine restricts its energy extraction capability from the ocean waves. In this work, the concept of a radiused edge tip blade (RETB) was introduced to overcome such an issue. The RET modifies the tip and changes the tip leakage flow behaviour. The flow through the turbine annulus was simulated numerically and...
The Wells turbine is a self-rectifying air turbine, used in oscillating water column (OWC) to harvest wave energy. It produces unidirectional torque as the flow oscillates inside the OWC chamber. It has inherent disadvantage of narrow operating range due to stall at high airflow rate. Whereas, a wider operating range is essential to improve the tur...
Marine energy is a major source of renewable energy and yet remains untapped. As the ocean covers about two-thirds of the Earth’s surface, it contains a large amount of energy. Energy can be extracted from the sea exploiting several phenomena, such as salinity gradient (energy from the difference in the salt concentration between seawater and fresh...
Abstract: Gauss-Seidel method is one of the simplest available iterative methods for solving systems of linearized equations. It can effectively reduce high frequency errors but performs poorly with errors of low frequency. Multigrid (MG) utilizes this quality of the point-wise methods by successively coarsening the grid, so that the lowest frequen...
The oscillating water column (OWC) based wave energy devices require a turbine for the conversion of wave energy to electrical energy. Customarily, Wells and impulse turbines have been widely accepted for this energy conversion. However, the damping (i.e. the pressure drop developed based on volume flow rate) induced by the turbine significantly in...
![Figure 1. Growth in Indian Power sector [1].](publication/348449876/figure/fig1/AS:979891407290370@1610635725473/Growth-in-Indian-Power-sector-1_Q320.jpg)
![Figure 5.a) The SeaGen system full view [31]. b) The SeaGen system...](publication/348449876/figure/fig2/AS:979891407302659@1610635725605/a-The-SeaGen-system-full-view-31-b-The-SeaGen-system-adopted-in-Strangford-lough-UK_Q320.jpg)
India has about 7500 km of coastal lines with a significant potential to harvest marine energy. Tidal energy, one of the types of marine energy that emerges has a practical option to supply reliable and renewable energy to the Indian coastal areas. This paper focuses on tidal current turbines that can be adapted to various potential sites available...
![Figure 3. Energy from tidal stream [33]. 3. Results](publication/348450685/figure/fig1/AS:979891457630208@1610635737378/Energy-from-tidal-stream-33-3-Results_Q320.jpg)
![Figure 5. Moored buoys located around India [54].](publication/348450685/figure/fig2/AS:979891457650689@1610635737441/Moored-buoys-located-around-India-54_Q320.jpg)
![Figure 6. Moored buoy [54]. Figure 7. Average monthly current speed...](publication/348450685/figure/fig3/AS:979891457626113@1610635737470/Moored-buoy-54-Figure-7-Average-monthly-current-speed-measured-by-AD09_Q320.jpg)
![Figure 8. The bathymetry profile of the Minicoy beach [57].](publication/348450685/figure/fig4/AS:979891457646602@1610635737526/The-bathymetry-profile-of-the-Minicoy-beach-57_Q320.jpg)
![Figure 9. Tidal turbine using a generator [60].](publication/348450685/figure/fig5/AS:979891457630210@1610635737553/Tidal-turbine-using-a-generator-60_Q320.jpg)
The islands in the Indian Ocean as other remote islands are often challenged to meet their energy needs, and constantly getting electricity from the mainland is expensive. In this article, the present scenario and future prospects of the energy sources for all the Indian islands are discussed. Data collected from different buoys of INCOIS are analy...
The oscillating water column type wave energy converters equipped with Wells turbine are one of the popular wave energy conversion devices. In most of the numerical and experimental studies, the Wells turbine characteristics are examined in no-load condition or with a fixed loading to achieve a fixed rotational speed. In the present work, a biplane...
A bidirectional impulse turbine is a self-rectifying air turbine used in an oscillating water column wave energy converters. Most of the study on bidirectional impulse turbines involves steady-state performance analysis; however, the performance under oscillating airflow conditions is necessary to understand its behavior. The objective of this stud...
Oscillating water columns (OWC) are widely used devices for the extraction of wave energy through self -rectifying impulse air turbines. To improve the performance of any turbo-machinery, guide vanes (GV) play an essential role in deciding turbine characteristics in terms of efficiency and torque. The concept of filleting is used in the GVs of bidi...
The Wells turbine is one of the candidates for use in Oscillating Water Column (OWC) type wave energy conversion devices. The narrow operating range of a Wells turbine limits its application to a small range of ocean environments. At a high angle of attack, the turbine performance drops suddenly due to a phenomenon known as stall. The present study...
A marine current turbine (MCT) that extracts energy from ocean currents should be hydrodynamically and structurally stable to generate uninterrupted power. This can be achieved through the shape optimization of MCT blades. In this work, a horizontal axis MCT of 0.8 m diameter was optimized through multi-fidelity numerical approach. The design param...
This work deals with unsteady analysis and control of a bi-directional impulse turbine equipped in oscillating
water column (OWC) wave energy converter (WEC). The Unsteady Reynolds-averaged Navier-Stokes equations
(URANS) were solved to get the turbine characteristics and the maximum efficiency tracking for different axial
velocities. The groupe...
A bidirectional turbine used in an oscillating water column device extracts wave energy from oscillating airflow. To improve its power output, a concept of static extended trailing edge found in the wings of owl and merganser was adopted. The static extended trailing edge with 0–10% of chord length (C) was analyzed for different flow coefficients v...
Gauss-Seidel method is one of the simplest available iterative methods for solving systems of linearised equations. It can effectively reduce high frequency errors but performs poorly with errors of low frequency. Multigrid (MG) utilises this quality of the point-wise methods by successively coarsening the grid, so that the lowest frequency errors...
This paper deals with the efficiency maximization of a wave energy converter (WEC). The WEC is an oscillating water column (OWC) device and drives a permanent magnet synchronous generator (PMSG) through a bidirectional flow impulse-turbine. The converter faces challenges such as large peak-to-average power ratio, low overall efficiency, and ineffic...
A Gurney flap (GF) placed at pressure side of the trailing edge of an airfoil and perpendicular to the chord line enhances lift in aircraft wings, helicopter rotors, and wind turbines, etc. In this article, the GF concept was introduced for Wells turbine blade used to harvest wave energy with special consideration as the blades are having symmetric...
Drawing on extensive research and experience, this timely reference brings together numerical optimization methods for fluid machinery and its key industrial applications. It logically lays out the context required to understand computational fluid dynamics by introducing the basics of fluid mechanics, fluid machines and their components. Readers a...
In the oil and gas industry, upstream and downstream hydrocyclones are used extensively to separate heavy or dense particles from the formation water/reservoir fluids. These hydrocyclones, after a long period of operation, can fail as a result of wear-initiated leakage, thereby needing maintenance or replacement. A detailed investigation of this fa...
The Wells turbine is used in conjunction with an oscillating water column to harvest wave energy. It is a self-rectifying axial flow reaction turbine which consists of symmetrical blades aligned normal to the incoming flow. A narrow operating range due to flow separation restricts the power extracting capability of the turbine at a higher flow rate...
Flow through a scaled horizontal axis marine current turbine was numerically simulated after validation and the turbine design was optimized. The computational fluid dynamics (CFD) code Ansys-CFX 16.1 for numerical modeling, an in-house blade element momentum (BEM) code for analytical modeling and an in-house surrogate-based optimization (SBO) code...
Numerical investigation on the effect of wing morphology of the dragonfly Aeshna cyanea is carried out to understand its influence on the aerodynamic performance. The two-dimensional wing section has corrugation all over the surface along the chord length on both upper (suction side) and lower (pressure side) surfaces. By considering each corrugati...
Drawing on extensive research and experience, this timely reference brings together numerical optimization methods for fluid machinery and its key industrial applications. It logically lays out the context required to understand computational fluid dynamics by introducing the basics of fluid mechanics, fluid machines and their components. Readers a...
Fluid mechanics has two parts: dynamics and kinematics. The kinematics describes the motion of the fluid without any consideration of the forces that cause fluid motion. Fluid motion where the forces are considered is called fluid dynamics. Fluid flows can be classified according to several criteria; for example, considering viscosity, compressibil...
This chapter discusses different optimization techniques mostly for surrogate‐based optimization. A decision‐making process in engineering depends on a single parameter or multiple parameters that affect the system performance. In surrogate‐based optimization, surrogate models approximate the data and predict approximate results. In multi‐objective...
Renewable energy sources are generally clean, emissions‐free power production resources. This chapter discusses few renewable energy resources. Among them, many use turbomachinery in one form or other. Wind turbine technology is dominated by very large open rotors of the horizontal‐axis type i.e. horizontal‐axis wind turbines (HAWTs). In optimizati...
This chapter describes optimization techniques for maximizing industrial fluid machinery performance. Both single‐ and multi‐objective methods are explained in detail that are capable of dealing with both single‐ and/or multi‐point problems. The most common and relevant problem type concerns shape optimization of machine stationary and rotating par...
Energy efficient generation from renewable energy sources is of major concern nowadays. A horizontal axis marine current turbine (HAMCT) of diameter 1.9 m is modelled using the blade element momentum (BEM) scheme and the turbine output parameters are given as an input to the electrical system for a tip speed ratio (TSR) of 5 and a power coefficient...
Wave energy converters (WECs) face difficulties such as low operating range, low power output and, fluctuating power. A seamless synchronization among WEC components is required to get a better performance. For control system studies, the model should capture all the necessary dynamics involved in each conversion stages, however the interlinked com...
Oscillating Water Column (OWC) is one of the most popular wave energy converters being used for the last two decades. The pneumatic energy from water waves inside the air chamber of OWC is converted into mechanical energy with the help of Wells turbine. Biplane Wells turbine has inherent advantage over the monoplane turbine in terms of starting cha...
The interest in wave energy converters (WECs) is increasing, the study of grid connection of WEC along with the control system has become inevitable. WEC such as an oscillating water column (OWC) device involves conversions in various physical domains, thus a model describing the conversions at each stage and coupling between them should be accurat...
Wells turbine is an axial flow air turbine extensively used in the oscillating water column (OWC) of ocean energy harvesting device. The turbine has low aerodynamic efficiency at higher flow rate and poor starting characteristics. In this paper, the characteristics of the hysteresis behavior of a Wells turbine for a wave energy conversion device un...
Ocean currents that are produced due to motion of tides can be utilized in power extraction by using suitable turbines. The turbine should be structurally and hydrodynamically strong. In this paper, a 0.8 m horizontal axis marine current turbine (MCT) with three blades is analyzed. A 3D CAD model of a turbine is optimized using CFD and FEA tools. T...
Three-dimensional numerical analyses were conducted to study fluid flow behavior over the rough surface in an electric submersible pump at the design and off-design conditions. The entire range of smooth, transition and fully rough surfaces was considered for the study of the turbulent boundary layer properties and its effect on the pump performanc...
This paper presents numerical study of the surface curvature effects on the performance of a 3D lab scale tidal turbine (E387) using Eppler 387 airfoil. The prescribed surface curvature distribution blade design method is used to remove the surface curvature discontinuity of E387 turbine and the redesigned turbine is denoted as A7 turbine. The two...
A Wells turbine with the static extended trailing edge is numerically investigated in this study. The static extended trailing edge (SETE) is shown to improve the lift characteristics in aircraft wings. The reference turbine is numerically validated against the existing experimental and numerical results. SETEs with various lengths are analysed and...
Cross-sectional geometry of a horizontal axis tidal stream turbine (HATST) blade was optimized using surrogate models and computational fluid dynamics (CFD) analysis. The blade thickness parameters of a 100 kW class HATST model, i.e., relative thickness and maximum relative thickness location, were varied to examine change of turbine performance in...
The hydrodynamic performance of a dual-rotor horizontal axis marine turbine (HAMCT) is investigated for the power gain in operating the rear rotor without blade-pitch control. This kind of turbine can be advantageous for a rectilinear tidal current of reversing directions, where each rotor blade is optimally fixed-pitched towards its upstream veloc...
A bidirectional axial‐flow impulse turbine installed in an oscillating water column raises the question of damping at different wave conditions. This article reports unsteady performances of such a turbine in an airflow test rig. The rig has a piston‐cylinder arrangement, and the piston, when reciprocating, generates the oscillatory airflow. At a v...
Wells turbine is a self-rectifying axial air turbine, which consists of symmetrical aerofoil at 90° stagger. It is used to extract power from the bidirectional airflow inside an oscillating water column. Generally, the performance of the turbomachines is affected by the turbulence intensity. In this numerical study, the effect of turbulence intensi...
Guide vanes (GVs) improve the performance of a turbine in terms of efficiency, torque, or operating range. In this work, a concept of different orientations of GVs in between a two-row biplane wells turbine (BWT) was introduced and analyzed for the performance improvement. The fluid flow was simulated numerically with a commercial software ANSYS CF...
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 draw...
Oscillating water column wave energy converter is having low efficiency because of its principal component, a bidirectional turbine. An analysis of the internal flow of the turbine gives an idea of improving the performance through optimization of geometrical parameters. In this study, an impulse turbine of 0.3 m diameter with fixed guide vanes is...
In the present work, a unique design using a direct mechanical drive based power takeoff system is proposed, designed, fabricated and tested for a point absorber. The power takeoff mechanism in the design consists of rack and pinion arrangement, which converts the bidirectional reciprocating motion to unidirectional rotation. This mechanism is fixe...
In this study, a variant of 3D split-and-recombine micromixer is proposed for enhanced micromixing. The mixing analysis was carried out for water and blood flows through the three-dimensional numerical model. The blood flow was modeled using several non-Newtonian fluid models existed in the literature and performance was compared for mixing index....
Low fidelity model assisted design optimization of turbomachines has reduced the total computational and experimental costs. These models are called surrogate models which mimic the actual experiments or simulations. The surrogate models can generate thousands of approximate results from a few samples, making it easy to locate the optimal solution....
A Wells turbine is an axial flow reaction turbine, which
consists of a symmetrical airfoil at 90° stagger. It is commonly
used as a power take-off device in the oscillating water column.
This turbine is prone to stall at higher flow coefficients and have
narrow operating range. There are several parameters, which
influence the stall characteristics...
The present paper investigates the leading edge (LE) undulations of a Wells turbine blade through numerical analysis. The aspiration for this modification came from humpback whales, which have uneven protrusions at the LE of their pectoral flippers. The flippers help whales to maneuver during swimming. The work is performed by using three-dimension...
Transporting slurry is a difficult task and industries use a kinetic or centrifugal pump or a screw or progressive cavity pump to deliver it. On the other hand, approximation models can help predicting performance and avoiding the expensive experiments of pumps with slurries. In this work, bentonite-based slurries were prepared and pumped by a cent...
It is well understood that the performance of any turbine is influenced by the blade profile and geometry. The geometrical parameters like chord length, leading and trailing edge ellipse ratios etc. influence the performance characteristics like efficiency, torque, power and pressure drop across the turbine. Therefore, the optimization of the blade...
Questions
Question (1)
Recently one of my articles got rejected by the Chief Editor of an ASME journal. The Associate Editor accepted and passed the article to the Chief Editor. The Chief Editor rejected it citing some reasons, and he did not give us any chance to respond to his concerns. I emailed him, he did not respond. Does any of you have such experience? How to handle such an issue?
