scholarly journals Dually Operated Control Cupola Furnace With Maintaining Constant Air Blast for Improving Production Gain of Iron

Cupola furnace is the most commonly used for the melting of ferrous metals and alloys. The key challenge in this paper is variation of air blast which lead to productivity loss and moreover affects the small scale industries. In order to overcome the above key challenge our work has proposed a Dually Operated Control Cupola Furnace which states that constant air blast can be obtained by controlling manually as well as automatic. Manual operation is obtained by maintaining constant Motor-Torque-Speed-Ratio using inverter driven blower along with space vector pulse width modulation. Automatic operation inhabits a feedback control system using nonlinear model predictive controller which is operated on control valve driven blower. Automatic operated cupola furnace obtains a prediction value for obtaining the productivity gain based on number of experimental observations and overall gives the required constant air blast by considering blast volume, blast temperature and oxygen enrichment. Thus our model enhances the system performance by achieving productivity gain in terms of melting rate and super heating temperature.

2018 ◽  
Vol 192 ◽  
pp. 02028
Author(s):  
Hassan Zulkifli Abu ◽  
Ibrahim Aniza ◽  
Mohamad Nor Norazman

Small-scale blast tests were carried out to observe and measure the influence of sandy soil towards explosive blast intensity. The tests were to simulate blast impact imparted by anti-vehicular landmine to a lightweight armoured vehicle (LAV). Time of occurrence of the three phases of detonation phase in soil with respect to upward translation time of the test apparatus were recorded using high-speed video camera. At the same time the target plate acceleration was measured using shock accelerometer. It was observed that target plate deformation took place at early stage of the detonation phase before the apparatus moved vertically upwards. Previous data of acceleration-time history and velocity-time history from air blast detonation were compared. It was observed that effects of soil funnelling on blast wave together with the impact from soil ejecta may have contributed to higher blast intensity that characterized detonation in soil, where detonation in soil demonstrated higher plate velocity compared to what occurred in air blast detonation.


2021 ◽  
pp. 1-37
Author(s):  
Mabrouk Mosbahi ◽  
Mouna Derbel ◽  
Mariem Lajnef ◽  
Bouzid Mosbahi ◽  
Zied Driss ◽  
...  

Abstract Twisted Darrieus water turbine is receiving growing attentiveness for small-scale hydropower generation. Accordingly, the need for raised water energy conversion incentivizes researchers to focalise on the blade shape optimization of twisted Darrieus turbine. In view of this, an experimental analysis has been performed to appraise the efficiency of a spiral Darrieus water rotor in the present work. To better the performance parameters of the studied water rotor with twisted blades, three novel blade shapes, namely U-shaped blade, V-shaped blade and W-shaped blade, have been numerically tested using a computational fluid dynamics three-dimensional numerical model. Maximum power coefficient of Darrieus rotor reaches 0.17 at 0.63 tip-speed ratio using twisted blades. Using V-shaped blades, maximum power coefficient has been risen up to 0.185. The current study could be practically applied to provide more effective employment of twisted Darrieus turbines and to improve the generated power from flowing water such as river streams, tidal currents, or other man made water canals.


2021 ◽  
pp. 1-16
Author(s):  
Ojing Siram ◽  
Niranjan Sahoo ◽  
Ujjwal K. Saha

Abstract The small-scale horizontal-axis wind turbines (SHAWTs) have emerged as the promising alternative energy resource for the off-grid electrical power generation. These turbines primarily operate at low Reynolds number, low wind speed, and low tip speed ratio conditions. Under such circumstances, the airfoil selection and blade design of a SHAWT becomes a challenging task. The present work puts forward the necessary steps starting from the aerofoil selection to the blade design and analysis by means of blade element momentum theory (BEMT) for the development of four model rotors composed of E216, SG6043, NACA63415, and NACA0012 airfoils. This analysis shows the superior performance of the model rotor with E216 airfoil in comparison to other three models. However, the subsequent wind tunnel study with the E216 model, a marginal drop in its performance due to mechanical losses has been observed.


Author(s):  
Nur Alom ◽  
Ujjwal K. Saha

The Savonius rotor appears to be particularly promising for the small-scale applications because of its design simplicity, good starting ability, and insensitivity to wind directions. There has been a growing interest in recent times to harness wind energy in an efficient manner by developing newer blade profiles of Savonius rotor. The overlap ratio (OR), one of the important geometric parameters, plays a crucial role in the turbine performance. In a recent study, an elliptical blade profile with a sectional cut angle (θ) of 47.5° has demonstrated its superior performance when set at an OR = 0.20. However, this value of OR is ideal for a semicircular profile, and therefore, requires further investigation to arrive at the optimum overlap ratio for the elliptical profile. In view of this, the present study attempts to make a systemic numerical study to arrive at the optimum OR of the elliptical profile having sectional cut angle, θ = 47.5°. The 2D unsteady simulation is carried out around the elliptical profile considering various overlap ratios in the range of 0.0 to 0.30. The continuity, unsteady Reynolds Averaged Navier-Stokes (URANS) equations and two equation eddy viscosity SST (Shear Stress transport) k-ω model are solved by using the commercial finite volume method (FVM) based solver ANSYS Fluent. The torque and power coefficients are calculated as a function of tip speed ratio (TSR) and at rotating conditions. The total pressure, velocity magnitude and turbulence intensity contours are obtained and analyzed to arrive at the intended objective. The numerical simulation demonstrates an improved performance of the elliptical profile at an OR = 0.15.


Electronics ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 187
Author(s):  
Intissar Moussa ◽  
Adel Khedher

An appropriate modulation scheme selection ensures inverter performance. Thus, space vector modulation (SVM) is more efficient and has its own distinct advantages compared to other pulse width modulation (PWM) techniques. This work deals with the development of an advanced space vector pulse width modulation (SVM) technique for two-phase inverter control using an XSG library to ensure rapid prototyping of the controller FPGA implementation. The proposed architecture is applied digitally and in real time to drive a two-phase induction motor (TPIM) for small-scale wind turbine emulation (WTE) profiles in laboratories with minimum current ripple and torque oscillation. Four space voltage vectors generated for the used SVM technique do not contain a zero vector. Hence, for an adequate adjustment of these four vectors, a reference voltage vector located in the square locus is determined. Considering the asymmetry between the main and auxiliary windings, the TPIM behavior, which is fed through the advanced SVM controlled-two-phase inverter (2ϕ-inverter), is studied, allowing us to control the speed and the torque under different conditions for wind turbine emulation. Several quantities, such as electromagnetic torque, rotor fluxes, stator currents and speed, are analyzed. To validate the obtained results using both Simulink and XSG interfaces, the static and dynamic characteristics of the WTE are satisfactorily reproduced. The collected speed and torque errors between the reference and actual waveforms show low rates, proving emulator controller effectiveness.


Author(s):  
Inri Rodriguez ◽  
Jesus Cerda ◽  
Daniel S. Codd

A prototype water-glycerol two tank storage system was designed to simulate the fluidic properties of a high temperature molten salt system while allowing for room temperature testing of a low cost, small scale pneumatically pumped thermal storage system for use in concentrated solar power (CSP) applications. Pressurized air is metered into a primary heat transfer fluid (HTF) storage tank; the airflow displaces the HTF through a 3D printed prototype thermoplate receiver and into a secondary storage tank to be dispatched in order to drive a heat engine during peak demand times. A microcontroller was programmed to use pulse-width modulation (PWM) to regulate air flow via an air solenoid. At a constant frequency of 10Hz, it was found that the lowest pressure drops and the slowest flowrates across the receiver occurred at low duty cycles of 15% and 20% and low inlet air pressures of 124 and 207 kPa. However, the data also suggested the possibility of slug flow. Replacement equipment and design modifications are suggested for further analysis and high temperature experiments. Nevertheless, testing demonstrated the feasibility of pneumatic pumping for small systems.


Author(s):  
Emre Hasan Dursun ◽  
Ahmet Afsin Kulaksiz

AbstractWhile the use of renewable energy systems in electric power generation is increasing more and more, wind energy conversion systems (WECS) receive considerable attention among these. Thanks to the ability of power generation in all wind speed range by controlling the rotor speed, Variable Speed WECSs are more preferred than fixed speed WECSs. When considering small-scale applications in variable speed WECS, Permanent Magnet Synchronous Generator (PMSG) based WECS structures are focus of the interest due to their advantages such as high efficiency and low maintenance costs. The generator must be operated at an optimum speed to obtain maximum power from the WECS. Moreover, different Maximum Power Point Tracking (MPPT) methods can be used to control and determine optimal operating speed. In this paper, WECS configuration consists of PMSG, uncontrolled rectifier, DC link capacitor, DC-DC boost converter and DC-Bus. Capturing the maximum power from WECS and supplying the DC-Bus is performed via tip speed ratio and PI control (TSR-PI) based MPPT method. Moreover, two wind speed profiles having constant and instant changes are created to test the performance of the proposed method. For comparison purposes, perturbation & observation (P&O) based MPPT method is also carried out in here. According to obtained results from this study performed in Matlab/Simulink environment, it is verified that TSR-PI based MPPT method ensures higher power and efficiency for these wind speed profiles by means of a more successful generator speed tracking.


2017 ◽  
Vol 43 (0) ◽  
pp. 43-49 ◽  
Author(s):  
Daiki Taniguchi ◽  
Yuki Narisada ◽  
Hiroaki Yamada ◽  
Toshihiko Tanaka ◽  
Tomohiro Tamura ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document