bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Investigation of Compressor Tandem Aerofoils Featuring Near-Endwall Modification
Authors: Eckel J , Gümmer V
Published: May 2021

A highly loaded 1.5-stage low-speed compressor stage is investigated numerically using fully turbulent and steady state RANS simulations. The tandem stator at the end of the stage is replaced by a tandem stator with a near-endwall modification. This unconventional compressor blade design is using a single profiling near both endwalls and a tandem profiling at midspan. Using this modification the positive behaviour of a tandem stator can be maintained. Locally the leading edge of the rear vane and as a result the gap flow near both endwalls will be removed by introducing a single-profile segment. This paper will describe the approach to set up a numerical model for the new geometry and will characterize the flow features and loss mechanisms of the near-endwall modification. The first comparison between the stators with and without near-endwall modification, showed a reduction of corner separation at the rear vane, caused by the removal of the low momentum gap-flow. On the other side, the near-endwall modification is creating higher losses at the connecting region between the tandem and single segment. The numerical results presented in this paper will be the starting point for further optimizations of the tandem blade with near-endwall modifications.
Design Concept with Tip Leakage Vortex Control for Centrifugal Compressor Flow Stabilization
Authors: Tomita Isao , Furukawa Masato
Published: May 2021

Centrifugal compressor applied to turbochargers is required to operate stably in wide range from choking to surging. In our past research, authors suggested a design policy called STB (flow Stabilization by inducing Tip leakage vortex Breakdown) concept, which indicates “Operating range can be enhanced with uniform blockage region generated by tip leakage vortex breakdown”. In this study, authors tried to validate the STB concept by redesigning a given impeller into a wide range compressor. In this research, detailed analyses showed that non-uniform and unstable stall occurred at small flow rate in the conventional impeller. On the other hand, in the redesigned new impeller having high inducer loading, unsteady numerical calculation showed that the strengthened blade tip leakage flow generated a circumferential uniform blockage region, which could stabilize its internal flow. As a result of performance test of the new impeller, considering that the surging flow rate at the same shaft speed was reduced by 3% and the pressure ratio at the surging point had been improved from 2.8 to 2.9, the surging flow rate at the pressure ratio of 2.8 could be reduced by 8%. In this way, it was found that the tip leakage flow was dominant with the stall phenomenon of the centrifugal compressor, and it was also confirmed that the STB concept was one of the effective means for the operation range enhancement.
Extensive Experimental and Analytical Investigation of the Aerodynamic Flow Field of Labyrinth Seals with Innovative Liner Configurations
Authors: Hühn Lisa , Wilhelm Julius , Schwitzke Corina , Bauer Hans-Jörg
Published: May 2021

The state-of-the-art sealing systems in aircraft engines are labyrinth seals to regulate mass flow between rotating components. To prevent structural damage of vital parts during a rubbing process, abradable liner configurations with hollow body structures are applied on the stator. Compared to smooth stator surfaces, these structures increase the cross-sectional area of the sealing gap and, thus, lead to a higher leakage. The aim of this paper is to identify the main geometrical parameters influencing the aerodynamic behavior of various liner configurations. As a basis of an analytical study, an extensive experimental database is required. For this purpose, a test rig is set up at the Institute of Thermal Turbomachinery (ITS). Three liner structures (honeycomb, rhombus, and polyhedral structures), two seal fin configurations, and the effect of the adjusted nominal clearances (0.1-1.0 mm) and different pressure conditions are investigated. The experimental results will be presented, discussed, and evaluated by means of established parameters. The focus is on the leakage of the seal, the discharge coefficient, and the equivalent gap width. Additionally, the influence of the geometric shape of the liner structures is discussed. Flow separation and flow direction play the main role. With the results of this paper, optimization guidelines are derived for the design of innovative liner configurations.
Supervised Learning for Generating Fair Curves with Curvature Boundary Conditions
Authors: Sudhof Samuel , Uemura Norimichi , Uchiumi Masaharu
Published: May 2021

Fairness measures are means to guess if a curve is suited for an aerodynamic application if no knowledge of the flow field is available. Fair curves are proposed as a means to reduce the number of parameters for generating a supersonic rotor blade. A specific new measure of fairness is proposed with the goal of being numerically less demanding to evaluate than previously known measures of fairness. Gradient search for an optimum of this fairness value is nevertheless computationally expensive. Therefore, a neural network was trained using Adamax optimization that can produce curves of acceptable quality instantly for applications where real time response is needed.
Optimization procedure to design a Francis turbine runner using 2D Through-flow analysis
Authors: Watanabe Ryo , Miyagawa Kazuyoshi , Khozaei Mohammad Hossein , Yamaguchi Naoki , Masuko Toshitake
Published: May 2021

Due to increasing usage of Feed-in Tariff (FIT), which is a subsidy system to encourage expansion of renewable energy and to reduce costs associated with introduction of renewable energy, demand for hydraulic turbine designers has increased solely for the purpose of improving turbine performance. With these requirements, CFD simulation is a powerful tool for designers to improve the internal flow and pressure distribution in turbines. Traditionally, most designers use a trial-and-error process based on previous experience to design new turbines. Usually, achieving the goal is a lengthy and painstaking process. This paper proposes a novel method which combines both CFD and optimization methods to automatically optimize a Francis turbine. This procedure includes four components: a design program, a CFD solver, a scheduler, and an optimization algorithm. This paper describes an attempt to automatically optimize a Francis turbine runner by using ANSYS Vista TF as the 2D CFD solver based on through-flow theory, and ANSYS CFX 19.1 as the 3D CFD solver based on Finite Volume Method (FVM). The runner geometry is parameterized by Bezier curves in the design program. CFD analysis is performed to assess the efficiency of the runner, and also the output power is calculated by runner torque. These two parameters are used as the objective function of the optimization algorithm. This method is used to optimize the runner geometry, which consists of two parts: the meridional plane and profile camber lines. We confirmed that the new turbine, which was optimized by the above-mentioned method, has better efficiency than the existing one.
Transient Characteristics of a Centrifugal Pump at Rapid Startup
Authors: Tanaka Teiichi , Toyomoto Takeshi , Nasu Kosuke , Tabaru Michiya
Published: May 2021

An experimental and CFD(Computational Fluid Dynamics) study was conducted on the transient behavior of a rapidly starting centrifugal pump. The transient characteristics of the centrifugal pump in the transient period were examined from experimental results. Instantaneous flow rate and pressure were measured at suction and discharge ports of the pump with rotational speed and pump shaft torque when the pump is in transient operation. The suction and discharge pressures of the pump were measured by pressure sensors of the strain gauge type. The unsteady flow rate was calculated based on the pressure difference between two pressure measurement points in the straight suction pipe of the pump. The unsteady pump rotational speed and shaft torque were measured using the highly responsive torque meter. The true pump total head because of the pumping action at the unsteady operation of the pump was able to be calculated by subtracting the apparent pump total head cause by the fluid inertia effect from the measured pump total head. According to the present study, the transient characteristics of the rapid starting pump can be measured using the experimental setup. And it was shown that the dynamic operating point and shaft torque during the pump startup period deviate from the quasi-steady change. Comparing the experimental results with CFD, the reason for the deviation of transient characteristics from quasi-steady change was considered to be due to that the formation of the flow field in the pump during the transient period is delayed relative to the flow field of the steady-state.
Evaluation of self-induced oscillation of the flow control valve by fluid structure interaction analysis
Authors: Fukao Shinji , Futahasji Kensuke , Umehara Ryuichi , Baba Takeo
Published: May 2021

In the flow control valve used in the upper or the lower stream of a turbomachinery, when opening is small, the self-induced oscillation resulting from a clearance gap flow may occur. In this study, the mechanism of self-induced oscillation which occurs on the small valve opening condition was examined. And a concept to control the self-induced oscillation was built. The air model test of the flow control valve was carried out, and it was confirmed that self-vibration occurs under specific conditions. Moreover, stability evaluation using CFD was carried out, and it checked that the calculation results become the almost same tendency as a test results. The area where the instability force is generated on a valve was grasped from the simulation results, and it checked that stability was changed with flow field differences. Based on these results, stabilization of the flow control valve was attained by improving clearance gap geometry of the valve sheet area. It checked that the intended flow field was obtained in the geometry in CFD analysis, and it confirmed that fluid additive damping became positive in CFD.
Characteristics of fluid exciting force due to blade row interaction of a propeller turbine
Authors: Mori Ryosuke. , Ajiro Kazushi. , Miyagawa Kazuyoshi.
Published: May 2021

As the use of renewable energy is promoted, much researches on propeller-type turbines are carried out. To improve reliability, it is important to evaluate the fluid exciting force due to blade row interaction that may cause vibration or fatigue fracture. In this paper, CFD(URANS) simulations and experimental studies were conducted to understand the characteristics of the fluid exciting force due to blade row interaction of a propeller turbine. To evaluate the fluid exciting force, strain gauges and pressure sensors were used in the closed-loop water channel. The fluid exciting force acting on the rotor due to the stator was measured by changing stator load type and the rotor-stator distance. Based on the difference in the attenuation tendency of potential interaction and wake interaction due to changes in the rotor-stator distance, the influences of these interactions could be distinguished. As results of experiments and computation, wake interaction affecting pressure fluctuation was hardly attenuated due to the swirling flow and changing the rotor-stator distance has little effect on the attenuation of blade row interaction.
On the stability of boundary-layer flow over a rotating cone using new solution methods
Authors: Hussain Zahir , Garrett Stephen J.
Published: May 2021

In this study, a new solution is applied to the model problem of boundary-layer flow over a rotating cone in still fluid. The mean flow field is perturbed leading to disturbance equations that are solved via a more accurate spectral numerical method involving Chebyshev polynomials, both of which are compared with previous numerical and analytical approaches. Importantly, favourable comparisons are yielded with existing experiments [17] and theoretical investigations [6] in the literature. Meanwhile, further details will be provided of potential comparisons with new experiments currently in the pipeline.

Physically, the problem represents a model of airflow over rotating machinery components at the leading edge of a turbofan. In such applications, laminar-turbulent transition within the boundary layer can lead to significant increases in drag, resulting in negative implications for fuel efficiency, energy consumption and noise generation. Consequently, delaying transition to turbulent flow is seen as beneficial, and controlling the primary instability may be one route to achieving this. Ultimately, control of the input parameters of such a problem may lead to future design modifications and potential cost savings.

Our results are discussed in terms of existing experimental data and previous stability analyses on related bodies. Importantly, broad-angled rotating cones are susceptible to a crossflow instability [6], visualised in terms of co-rotating spiral vortices, whereas slender rotating cones have transition characteristics governed by a centrifugal instability [9], which is visualised by the appearance of counter-rotating Görtler vortices. We investigate both parameter regimes in this study and comment on the accuracy of the new solution method compared with previous methods of solving the stability equations.
Improvement of compact Darrieus-type hydraulic turbine for extra low head by changing inlet shape
Authors: Kikugawa H , Kawano Y , Shuto M , Furukawa A
Published: May 2021

Hydraulic power generation has a potential as an environmental friendly energy, which is not discharging a carbon dioxide gas during operation. Currently, high and middle water head turbine has been fully developed in practical use. However, extra low head hydraulic turbine has not been developed yet as a commercial utilization. Compact Darrieus-type hydraulic turbine has been focused on for small waterway. The purpose of this study is to improve the performance of the compact Darrieus-type hydraulic turbine, by changing inlet shape. In our previous study, the blade shape, the number of blades, the water wheel diameter ratio of chord length and pitch circle radius are optimized. The purpose of the present study is to further improve the performance of the compact Darrieus-type water turbine based on former results. In this study, the inlet shapes were changed to increase inflow velocity and to contribute improvement of efficiency. As a result, the efficiency of the turbine with using only half side counterpart nozzle was increased compared to the other settings.
Numerical calculation of the rotordynamic coefficients of a LOX-Turbopump Seal for the LUMEN LOX/LNG demonstrator rocket engine
Authors: Müller Max Axel , Traudt Tobias , Schlechtriem Stefan
Published: May 2021

In rocket engines seals are one of the key elements for a successful turbopump operation. They are not only responsible for reducing the leakage but they also have a huge influence on the rotordynamic behaviour. Depending on the design, the seal on a turbopump impeller can damp or excite rotordynamic instabilities. In this work we present transient 3D CFD simulations of straight gap seals, which are used to determine the rotordynamic coefficients. After that the numerical simulation is extended to characterize the influence of the impeller to housing clearance and swirl brakes on the rotor dynamic coefficients. We show that the inertia term cannot be neglected for the investigated nominal rotational speed of the rotor and high absolute whirl frequency ratios especially for the rotor housing clearance. Finally the coefficients calculated by numerical simulation are used in the equations of motion for a floating ring seal and the equations are solved numerically to do a sensitivity study of a floating ring to variations in axial force, rotor displacement and floating ring mass.
Influence of Rotational Speed of an Inducer on the Propagation Velocity of Super-synchronous Rotating Cavitation
Authors: Kondo Sota , Kanamaru Moena , Kawasaki Satoshi , Iga Yuka
Published: May 2021

The phenomenon that a cavity rotates faster than the rotational speed of the pump in the direction of rotation is called super-synchronous rotating cavitation (super-S RC). It is known that super-S RC is often observed in rocket turbopumps, but that it is rare to be observed in industrial pumps. Therefore, we form a hypothesis that its occurrence is related to the rotational speed of pumps. In this study, experiments of an inducer were conducted at four rotational speed at Kakuda Space Center in the Japan Aerospace Exploration Agency. The pressure fluctuation and the rotor vibration were measured, and the propagation velocity ratio of super-S RC and the frequency of unsteady cavitation in the super–S RC were determined at each rotational speed. As a result, when the cavitation number is the same, the propagation velocity ratio is almost the same regardless of the rotational speed of the inducer. It means that the faster the rotational speed, the faster the unsteady cavitation oscillates in the inducer despite the condition of the same cavitation number. It indicates that rotating cavitation does not occur under a certain rotational speed because of the limitation of the frequency of unsteady cavitation, which is known in hydrofoil.
A Straight-Bladed Vertical-Axis Turbine for Wave Energy Conversion: Effect of Guide-Vane Geometry on Performance
Authors: Hayamizu Y , Kitano K , Suzuki T , Morita S , Ohtsuka S , Takao M , Kinoue Y , Setoguchi T
Published: May 2021

This study proposes a straight-bladed vertical-axis turbine for ocean-wave energy conversion. The aim is to develop a novel air turbine suitable for an oscillating water column in a wave energy plant. To this end, the performances of straight-bladed vertical-axis turbines were investigated for different guide-vane geometries in a wind tunnel experiment. The rotor has four straight blades with an NACA0018 profile, a chord length of 80.5 mm, a pitch diameter of 460 mm, and a blade width of 490 mm. In this study, the guide-vane geometry was varied as arc, semi-arc, and semi-arc with a straight part. Under steady flow conditions, the turbine performance was evaluated by determining the torque, input and flow coefficients, and the turbine efficiency. The semi-arc blade geometry decreased the input coefficient and increased the torque coefficient. Moreover, the semi-arc blade with a straight part improved the starting characteristics of the turbine and its efficiency over a wide range of flow coefficients.
Fundamental Study on Improvement of Performance of Wells Turbine Blade
Authors: Isatake Naoya , Yamanouchi Kousuke , Hamakawa Hiromitsu , Kurihara Eru , Hayashi Hidechito
Published: May 2021

In the present paper the attention is focused on the effect of the dimples on the stall characteristics and aerodynamic sound radiated from two-dimensional airfoil. In general, two-dimensional blade is used as the airfoil of Wells turbine. We measured the lift force acted on the airfoil and aerodynamic sound. The dimples were effective to improve the stall characteristics. As the dimple diameter and number of dimples increased, the broadband noise at higher frequency component increased slightly compared with normal airfoil. The dimples were not effective to reduce the broadband noise radiated from airfoil. In contrast, the dimples were effective to reduce the discrete tone noise radiated from airfoil. This noise depended on the geometry, position and number of dimples. The suitable geometry, position and number of dimples were discussed to improve the stall characteristics and reduction of aerodynamic sound.
Particle Behavior in Curved Microchannels: Aspect Ratio Effects
Authors: Hayamizu Y , Nakamura A , Hyakutake T , Gonda T , Morita S , Ohtsuka S , Yanase S
Published: May 2021

The sorting devices of microfluidic systems operate by both passive and active mechanisms. The microchannels of these systems are often curved to cope with secondary flows, which allow sorting or mixing. Therefore, it is essential to characterize the secondary flows in microfluidic systems. In this study, we investigate the particle behavior in a spiral rectangular microchannel and clarify the effects of the aspect ratio and Dean number De on particle sorting by comparing experimental and numerical results. We fabricated Archimedean spiral microchannel models with the rectangular cross-section of millimeter-scale dimensions. Particle sorting in the microchannels was observed by the particle-tracking velocimetry (PTV) method. In addition, the particle-sorting mechanism was analyzed by the particle-tracking method in three-dimensional numerical simulations. When particle density exceeded water density, good sorting was observed when 20 < De < 40. The numerical particle-sorting behaviors agreed well with the experimental results.
Development and numerical assessment of a regulation strategy for Sliding Rotary Vane Expander based on revolution speed variation
Authors: Fatigati F , Bartolomeo M Di , Battista D Di , Cipollone R
Published: May 2021

Sliding Rotary Vane Expanders (SVRE) are widely used in ORC-based power units for waste heat recovery in internal combustion engine (ICE) thanks to the capability to handle off-design conditions and their lower speed. In particular, SVRE revolution speed is usually varied together with the pump one to regulate the recovery unit. Nevertheless, this parameter affects SVRE performance and such effects should be taken into account. Thus, in order to reach this goal, in this paper a control strategy based on revolution speed variation was developed for SVRE. Its suitability and effects on expander performance were analyzed through a SVRE model developed in GT-Suite™ environment. The model was experimentally validated thanks to an extensive experimental campaign carried out on a 1.5 kW SVRE installed on an ORC-based power unit fed by the exhaust gases of a 3 liters supercharged Diesel engine. The results confirm the regulation strategy effectiveness as the maximum deviation between the intake-end pressure (object of regulation) and the set-point is 4% of its value for a wide range of operating conditions. Moreover, the numerical results show that the increase of revolution speed until a certain value leads to the expander global efficiency increase and mechanical power too.
Influence of engine torque fluctuations on performance characteristics of pumps mounted on vehicles
Authors: Kawahara Takuma , Takamiya Hideaki , Motono Hitoshi , Hotta Yasuhiro , Miyagawa Kazuyoshi
Published: May 2021

A fire pump mounted on the fire engine is driven by a car engine. The engine has plurality of combustion chambers and converts the reciprocating motion of the pistons into rotational motion while shifting the combustion timing of each combustion chambers. When the force generated by the combustion is converted into torque, periodic torque fluctuation is generated. Torque fluctuation finally generates the rotation fluctuation. We analyzed pump performance by the rotation with the sinusoidal fluctuation for the impeller. From the viewpoint of torque and total head, each variable fluctuated in the same phase, but it was confirmed that there was a difference in fluctuation range. With engine rotation fluctuation given to the pump, we verify the pressure characteristics and efficiency on the outlet side change by CFD. In this paper, therefore, we report the results of CFD on pump output characteristics when periodic rotational fluctuations occur due to unsteady torque characteristics of the engine.
Effect of suction pipeline resistance on cavitation surge in a turbopump with inducer
Authors: Tanaka Y , Kitabata T , Nasu K , Watanabe S , Ohashi S , Sakata A
Published: May 2021

Cavitation surge is one of the vital flow instabilities in turbopumps, which should be avoided in actual operation. According to the past stability analyses, it is shown that the suction pipeline resistance has a suppression effect of cavitation surge. In the present study, we experimentally examined this effect by changing the suction pipeline resistance through the opening of butterfly valve installed upstream of inlet pipe. As a result, it was found that the onset range of cavitation surge could be significantly narrowed by the large suction pipeline resistance, which agreed with the above finding by the theoretical analyses.
A comparative study on accurate prediction of cavitation characteristics for head drop in a mixed-flow pump with steady- and unsteady-state analysis
Authors: Kim Yong-In , Kim Sung , Yang Hyeon-Mo , Lee Kyoung-Yong , Lee Yong-Kab , Choi Young-Seok
Published: May 2021

The cavitation characteristics for the head drop in a mixed-flow pump were investigated with the steady- and unsteady-state analysis. Two mixed-flow pump models exhibiting a different incidence angle were analyzed under the cavitation condition. The model with a larger incidence angle obtains relatively poor suction performance. Moreover, the steady-and unsteady-state analysis indicate different head level under the cavitation condition. The results of the unsteady-state analysis are more accurate to the experimental results. The head of a fully convergent steady-state analysis is not even distributed in the head fluctuation range of the unsteady-state analysis. However, the head drop due to the decrease of inlet pressure has almost the same distribution and gradient. In addition, the amount and shape of the bubbles were presented with the time variation, which were also compared with the averaged result of steady-state analysis. The bubbles show a larger oscillation in the model which has a larger incidence angle. The oscillation of the bubbles is related to the magnitude of the head fluctuation.
Feasibility study for the application of a neural network for operating condition detection of a centrifugal pump
Authors: Feng Jun , Böhle Martin
Published: May 2021

Artificial intelligence (AI) technology is successfully used in many fields. Originally, AI was developed for image and voice recognition and has been spread out on other fields like detecting deceases, behaviour, traffic movement etc. AI is also applied in fluidmachinery, for example in order to detect defaults in pumps, fans, compressors and turbines.

This work verifies the feasibility for the application of a neuronal network (NN) for operation point detection of an impeller pump by vibration signals. Once the NN is trained with the vibration signal, it can recognize the operating point by the vibration signal of the impeller pump.

In order to test whether the neural network method is feasible, a pump loop system was built up, which contains a radial centrifugal pump with a replaceable impeller. The vibration signal of the impeller pump is taken for different operating points and used for training a NN. In the first step a simple self-programmed NN in C++ is applied in order to find out a convenient NN-topology for operating point detection. The congruence rate of this simple NN method already reaches about 90%. The research results in this paper show that an operating point can be detected by the application of a simple NN. It is carried out how large the influence of the topology of a NN is in regard to the congruence rate (CR). By further application of AI like convolutional layers, batch normalization etc. a better CR seems to be very likely. From this point of view this contribution reports about a starting point of operating point detection of impeller pumps by the application of a NN.
Development of A High-Load Capacity Test Rig to Evaluate the Static Performance of Process Fluid-Lubricated Thrust Bearings
Authors: Bian Zheng , McClean Sean , Delgado Adolfo , Patil Abhay
Published: May 2021

Electrical submersible pumps (ESPs) are artificial lift devices widely used in the oil and gas industry to increase production. For unconventional wells, which includes subsea applications, installation cost is an order of magnitude higher than the cost of the typical ESP, thus pump reliability is paramount. Contamination of the thrust bearing lubricant oil by process fluid due to seal failures is one of the leading causes of thrust bearing failure. While improving seal reliability can prevent thrust bearing failures, an alternative approach is to develop process-fluid lubricated thrust bearings. This research aims to characterize and study the performance of thrust bearings operating with process fluid lubrication. A component level-level test rig for testing the performance of thrust bearings in any mixture of water, sand, and air is designed, built, and commissioned. Initial tests of the PEEK and Tungsten Carbide (WC) bearings include a load capacity test to determine the hydrodynamic limit of the bearing, a hydrodynamic test to corroborate test rig stability, and a wear test to determine if the bearings can operate feasibly past hydrodynamic limits in a mixed lubrication regime. Initial results show that lubrication starvation can occur in an unpressurized chamber for low viscosity fluids that are not supplied directly to the bearing. Furthermore, the film thickness, temperature rise in the pads, and load capacity all are lower for water lubricated bearings when compared to oil lubricated bearings. Results suggest that liner material affects wear rate but not load capacity; however, operating even the WC bearings past hydrodynamic limits causes substantial wear and is not recommended as an operating mode. Polycrystalline Diamond (PCD) coated mixed lubrication bearings were also tested. These bearings, although requiring higher drive torque, sustained higher loads than the tilting pad bearings without significant wear
Development of High Specific Load Direct Lubricated Two Pads Journal Bearing
Authors: Yamawaki T , Yoshimine C , Nakano T , Waki Y , Sumi Y
Published: May 2021

MHPS and MHI suggest HP/IP/LP separate casing and one bearing/rotor (one bearing between two casings) type steam turbine. To design this type of shaft arrangement, journal bearing that supports high specific load with superior oil film static and dynamic characteristics is demanded. In this paper, it is shown that 610 mm diameter direct lubricated two pads bearing which can operate at high specific load has been developed. Also, it is confirmed that its good bearing characteristics in full scale test.
Development of turbocharger engine system using 3D and 1D simulation to achieve 50% brake thermal efficiency
Authors: Nakamura Yohei , Miyagawa Kazuyoshi , Moriyoshi Yasuo , Kuboyama Tatsuya
Published: May 2021

In recent years, automobile exhaust gas regulations have become stricter due to environmental problems such as global warming. A project by the Cabinet Office called the Strategic Innovation Promotion Program (SIP) began in 2014. SIP has 11 themes in total. One of them, innovative combustion technology, aimed to improve the thermal efficiency of automobiles from the existing 40% to 50%. To improve the thermal efficiency of the automobile, it was essential to improve the efficiency of the turbocharger. In this study, we developed a turbocharger for gasoline and diesel engines. First, to confirm the efficiency of the conventional turbocharger, experiments and CFD analysis of a commercial turbocharger were performed. ANSYS-CFX was used as a numerical code. To confirm the accuracy of the CFD, the CFD results were compared with the experimental results, and it had good agreement with the experimental results. From the analysis results, the loss region of the conventional turbocharger was clarified. The designed turbocharger compressor was tested as a prototype compressor. The results of the compressor had good agreement with CFD results, so it was confirmed that the accuracy of CFD and design method was valid. Finally, A one-dimensional simulation using GT-Power which is a system analysis software for automobiles was performed to evaluate the developed turbocharger on the engine. In the fifth year of the project, the target efficiency of 50% was achieved.
Bio Remediation of Petroleum Contaminated Landfill Dump Sites
Authors: Maruthi Venkatesh K , Anusha G , Arumairaj P D
Published: May 2021

Bioremediation is the process using living organisms to clean up contaminated soil. The main advantage of bio remediation is that it allows soil to be treated without being excavated or transported. The rate at which microorganism degrade contaminants is influenced by specific contaminants and their concentration, oxygen supply, moisture, temperature, pH value, nutrients supply and bio augmentation. Treatability studies are conducted to determine the effectiveness of treatment process performance. In this project work, the work is carried out in three phases. In the first phase, the landfill sites in and around Chennai are visited to collect samples. The site characterization and soil analysis are done for five landfill sites. In the second phase, the soil samples collected are subjected to nutrient bio remediation. The effect of pH, temperature and biomass concentration is studied over a period of 30 days. The optimum condition for a good remediation of contaminated soil is achieved.
Assessing the Demand of Road Infrastructure Adjacent to Terminal Stations
Authors: Logeswaran S , Saravana Kumar P , Kavitha R , Rajkumar K , Manikandan P , Karthikeyan S
Published: May 2021

The aim of the research work is to find out factors affecting the road improvements for the roads adjacent to the bus terminus. Transport is the basic utility which serves for the people in the aspects of daily demand. The traffic existing around the core area of the city is usually high when compared with roads connecting city with highways. Bus transportation is the basic need for public transportation of a city. The demand of bus transportation increases day by day due to more usage of peoples migrates from various locations to the city area. The infrastructure development in bus terminus is still a big question mark whether the terminus improvement exists as per the increase in traffic capacity or not. The reason behind the analysis is that the improper arrangement of existing road furniture’s without any possibility for future expansion as per increase in demand. The solution for the traffic problem occurs around the bus terminuses was identified and the standards for the terminal elements were made. This helps the pedestrians and vehicles to make a smooth flow of traffic around the terminal area.
Experimental Investigation of Organic Waste Ash in Concrete
Authors: Rajeshkumar V , Elango K S , Vivek D , Anandaraj S , Vinodhini C , Kamalakannan P
Published: May 2021

Organic waste is one of the major wastes producing substances in the world. Recycling is done on plastics and other materials due to its high cost. The major constituents of concrete are cement and posses’ certain properties that cannot be replaced by any material. Usage of cement leads to environmental pollution, greenhouse effect. Replacement of cement with organic waste will reduce the cost, time and also reduces pollution. This paper focuses on replacement of cement partially with organic waste ash in 5%, 10% and 15% by weight on mechanical properties of concrete. The XRF test is used and the result shows organic waste ash is not a pozzolanic substance. The optimum performance is obtained at 5% replacement of cement by weight.
Microbial Composting
Authors: Anusha G , Maruthi Venkatesh K , Aravind M , Ramakrishnan S
Published: May 2021

Human population generates enormous amount of solid and liquid waste directly and produces industrial effluent indirectly. Due to usage of synthetic fertilizers and pesticides in the agriculture fields, man inflicts deep wounds on environment. Pollution is defined as undesirable changes occur in water, land and air. Waste generation has been observed to increase annually in proportion to the rise in population and urbanization. As more land is needed for the ultimate disposal of these solid wastes, issues related to disposal have become highly challenging.
Reuse of improved recycled concrete aggregates (RCA) for sustainable and environmental-friendly construction materials
Authors: Alyaseen Ahmad , Shah Siddharth , Solanki Ravindra , Daxini Bhavik , Alwani Yogesh K. , Alahmad Hussain
Published: May 2021

Recycled aggregates have an essential role in constructing construction activities today to save natural aggregates because of industrial development. The research aims to assess the suitability of recycled aggregates for the construction of new roads, which will help achieve road construction efficiency and help prevent environmental deterioration in the extraction and reducing pollution. In contrast with natural aggregates, recycled aggregates are of lower quality, mainly due to the cement mortar’s brittle nature attached to them. The point of the study is to increase the performance of RCAs in an environmentally friendly managing RCAs. In this process, RCAs are first soaked in acetic acid solution, in which acetic acid reacts with cement attached to the surface of the RCA. This reaction weakens the attached mortar and allows separating from the RCAs by using mechanical friction later. Treated RCAs have lower water absorption and more insufficient cement mortar adhesion. These RCAs used as aggregates in new the concrete increased the compressive strength, the tensile strength, and the concrete’s flexural strength by 26%, 11%, and 26% at 28 days, respectively. It is clean, safe, efficient, and a new method to be applied, so no harmful products are used, and no dangerous substances are incorporated into the RCAs that are being treated. The waste treatment solution was used as a supplementary admixture construction, increasing the concrete’s strength, and decreasing its environmental effects.
Contaminated water treatment with Activated charcoal build from cocoa pod husk
Authors: Sadheesh S , Shankar R , Santhosh Kumar S , Guru Prasath B
Published: May 2021

In this world, effluents released from the refinery affect the environment at major as different studies says that the natural agents have high capacity to absorb bivalent metal ions. Cocoa pod husk is widely produced in south India in minimum cost. During this study, the metal such as lead and copper was investigated. The cocoa pod husk is carbonized at five hundred degree Celsius and saturated with one molar hydrochloric acid at seven hundred degree Celsius in muffle furnace for two hours (atomic number-6). The final product is allowed to test by adsorbing the metals such as lead and copper to make different pH, dosage and contact time. The capacity to adsorb and metal removal percentage were documented when the contact time reaching two hours. The efficiency of the adsorbent to remove the heavy metal lead and copper was 78 % and 97% respectively.
Type Radiation Resisting High Density Concrete - A General Review
Authors: Thavasvi Arunachalam R , Vairava RM , Maruthachalam D
Published: May 2021

Exposure to very high levels of radiation, can cause acute health effects such as skin burns and acute radiation syndrome (“radiation sickness”). It can also result in long-term health effects such as cancer and cardiovascular disease. The Intensity of the radiation which a body receives is inversely proportional to the Thickness or density of the shielding material. Concrete is already an effective Shielding material but if its density is increased, it can be even more effective. Thus, producing high density concrete provides good resistant towards radiation. High density concrete is widely used in nuclear Powerplants and reactors to provide shielding against harmful radiations Emitting from the process of nuclear fission. It can be widely used in hospitals Where radioactive materials are used for medicinal purposes such as radiation Therapy, x ray imaging etc.
MHD Darcy-Forchheimer hybrid nanofluid flow past a nonlinear stretching surface: Numerical study
Authors: Sulochana C , Prasanna Kumar T , Uma M.S , Thulasi L
Published: May 2021

Numerical simulation of hybrid nanoliquid over a power law velocity stretching sheet with darcy forchhimer model is presented in this article. Similarity variable approach is applied to convert governing partial differential equations into ordinary differential equation then solved by shooting method. Impact of distinct flow parameters on momentum, energy and concentration profile is shown in graphs and heat transfer rate for two different hybrid nanofluid models(Ag Fe3O4/H2O and Ag MOS2/H2O) computed tabulated. Heat transfer rate is more in silver-iron oxide combination as compared to silver-molybdenum disulfide.
Adsorption of the Toxin Pesticide (Thiophanate - Methyl) from its Aqueous solution on the Surface of Activated Olive Seed
Authors: Hussein Zainab A , Abdulbari  , Mahood M , Alazzawi Rajwan A
Published: May 2021

The activated charcoal of olive seeds were used in this study to adsorb the toxin pesticide (Thiophanate-Methyl) from its aqueous solutions. The effect of the parameters such as initial concentration, contact time and temperature have been investigated. A thermodynamic analysis shows that the Thiophanate-Methyl removal by the olive seed’s activated charcoal was an exothermic and spontaneous process. The Langmuir and Freundlich models describe the adsorption isotherms, especially Langmuir model according to correlation coefficients. The results show that removing Thiophanate-Methyl by activated charcoal of olive seed from aqueous solution was very effective and has great potential applications in environmental protection.
Effect of Magnesium Oxide and Zinc Oxide Nanoparticles on Triiodothyronine Hormone
Authors: Salman Taghried A. , Ibrahim Tahseen Ali , Al-Rudha Abbas Salma Abd
Published: May 2021

The nanoparticles of magnesium oxide and zinc oxide are diagnosed through several techniques, including the Atomic Force Microscope (AFM) and (XRD). Analyzing the structure of studied nano materials are useful to investigate their medical applications by applying them to the triiodothyronine hormone in the serum. The concentration effect of zinc and magnesium oxides nanoparticles on triiodothyronine hormone were investigated. Results obtained revealed that zinc oxide nanoparticles gave an inhibitory effect. The highest inhibition to triiodothyronine hormone in the serum was achieved when the ZnONPs concentration is 200 ppm. On the other hand, magnesium oxide nanoparticles have no inhibitory effect on hormone action.
Electrical Discharge Machining of Super Alloys: A Review
Authors: Kumar R , Chauhan S S , Yadav D , Namdev S
Published: May 2021

In the current scenario, manufacturing industries faces difficulties during machining of engineering materials-metal based, having higher mechanical properties viz. higher strength, toughness and hardness through conventional machining methods. These problems include rapid tool wear, poor surface quality of work piece material and lower stock removal rate. EDM is a single prominent what more lucrative unconventional machining procedure is, finding its prevalent functions in motorized and aerospace industries for machining of harder materials that is super alloys. Super alloys are the heat-resistant category of metals maintaining their elevated potency at superior temperature. The present paper focuses on the past work done by the researchers on machining of super alloys viz. titanium, nickel and cobalt using EDM and Wire EDM process.
Analyzing the parking demand characteristics in cultural activity-oriented city
Authors: Vaishnavi Devi S , Abdul Wahab H , Gowtham S , Guru Gowtham G K
Published: May 2021

Transportation sector is a backbone for the economic development of any country. The urbanization rapidly increasing and it’s a challenge for the city planners to look into. The United Nations has projected that 67% of the global population lives in urban areas by 2050 compared to 50% in 2010 and a mere 10%-15% in the early 19th century. The factors for urban growth are the migration of the people from the rural areas to urban areas in search of jobs in industries, tourism, services, physical infrastructure facilities etc. Explosive urban growth leads to haphazard expansion of the city. The volume of motorized traffic is increasing in India which is expected to cross 130,000 billion passenger km and has potential in creating energy demand and carbon emissions from transport sector by 2050. The deceleration and acceleration of vehicle in the central business district causes emission and discomfort to the commuters. The width of the road is being occupied by the off-street parking of vehicle results in deceleration and acceleration of vehicle by the commuters which causes more congestion and delay along with emission in the temple city. Our study is to analyze the pattern of demand that arises in traffic dense area of Madurai to park the vehicles without causing any hindrance to the commuters travel in the road.
A Comparative Study of Adhesion Mechanism for Wall Climbing Robots: Ring Magnet vs. Block Magnets
Authors: Jose Jaise , Sugin Elankavi R , Dinakaran D , Kuppan Chetty R M , Ramya M M
Published: May 2021

Magnetic adhesion is widely used in wall climbing robots on ferromagnetic surfaces. The Ring and block Neodymium magnets provide the necessary adhesion in permanent magnet-based climbing robots. In this article, the effectiveness of ring and block magnets are analysed using FEMM. for various magnet configurations. The adhesion force generated by ring and block magnets of a similar volume is compared and analysed. The results showed that the adhesion of ring magnets increases with the thickness of magnets. The maximum adhesion achieved in various ring magnets was compared with the adhesion generated by the arrangement of block magnets for two standoff distances and it was found that the adhesion generated by the block magnets were better in both cases. The ring magnets have constant standoff distance as per the rubber coating used and this enables them to operate seamlessly on irregular surfaces while the block magnet configurations provide excellent payload capabilities. In summary, numerical simulation results provided an understanding of the areas where the ring magnets can be used and the areas where the block magnets serve the purpose better.
Performance Analysis of Jute Fiber As A Micro Reinforcement
Authors: Naveen Badavath , Logeshwari J
Published: May 2021

Soil is a base of the construction, which serves to upholds the design from underneath and to appropriates the heap successfully. Creating strength of sub-level has consistently been a huge perspective in highway and geotechnical designing fields. Clay soil has designing properties like low bearing limit and high compressibility. The improvement of soil properties is fundamental. There are numerous stabilizers to improve the strength of soil. In our daily life, it can be seen that the underlying foundations of vegetation (roots) balance out the close surface soil that has low shear strength, basically due to low compelling pressure, on both level and inclining grounds. To improve the strength of subgrade soil, the utilization of characteristic Jute fiber is a high-level technique and they are modest, locally accessible, and biodegradable. This current examination utilizes jute fiber as a stabilizer. Based on experimental data, it is determined that the unconfined compressive strength (UCC) strength of soil increases with adding jute and maximum dry density (MDD) of soil decrease and optimum moisture content (OMC) of the soil increases. It is found that jute fiber mixed with soil layer-wise gives better strength as compared to core and random mixing.