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Numerical simulation of a complete gas turbine engine working with inlet cooling of water injection has been evaluated using computational fluid dynamic (CFD), the influence of water droplet and injection rate on the compressor operation, engine combustion and the turbine were studied. The results obtained in contrast with dry compression unveil that, with minimum amount of water droplet and high...
Prediction of thermal conditions inside a vehicle cabin is still a challenge due to the transient behavior of this environment. A large number of research studies are addressing the subject of thermal comfort related to the in-cabin environment. This article is a part of a larger study, intended to deepen the knowledge on thermal comfort inside vehicles. The effect of different angles of airflow from...
The platinum price has decreased nearly 42% since 2010, forcing platinum mines to reduce expenses in order to remain profitable. Electricity consumption is a large capital expenditure for the mining sector and efforts should thus be made to reduce energy consumption while maintaining production. Compressed air networks were identified as a large energy consuming section in the mining industry. Inefficiencies...
Half-Rotating Wing (HRW) is a new type of analogous flapping wing system with rotating flapping used as a substitute for oscillating flapping. Estimating method of flight lift generated by HRW was one of the significant theoretical basis to design air vehicle. The working principle of HRW based on Half-Rotating Mechanism (HRM) together with the spanwise airflow and chordwise airflow generated during...
The present work numerically explores the performance characteristics of Darrieus turbine with NTU-20-V and NACA 0018 airfoils. The NTU-20-V airfoil was carved out to enhance the fatigue life of the aluminium extruded blades by reinforcing with glass fiber material in standard shapes. The earlier studies by the authors include conceiving the airfoil profile through genetic algorithm optimization followed...
Many challenges of modeling and control exist in the tail-sitter aircraft, including parameter uncertainty, highly coupling, nonlinearity, and external disturbance. In this paper, the model of a tail-sitter aircraft is simplified at the nominal condition to obtain the nominal linear invariant model. Then a robust controller based on the H∞ control theory is proposed to deal with the attitude tracking...
This paper presents the comparison of power captured by vertical and horizontal axis wind turbine (VAWT and HAWT). According to Betz, the limit of maximum coefficient power (CP) is 0.59. In this case CP is important parameter that determines the power extracted by a wind turbine we made. This paper investigates the impact of wind speed variation of wind turbine to extract the power. For VAWT we used...
In this paper, a complete numerical simulation model of helicopter flight dynamics was established. The modeling of the main aerodynamic components of the helicopter and the aerodynamic interference are taken into account, and the modeling methods of the airfoil aerodynamic model, the induced velocity model and the waving movement model are discussed in detail. Based on the hierarchical and modular...
We develop a theoretical power consumption model for multi-rotor Unmanned Aircraft Systems (UAS), estimate the model parameters, and validate it by flying an IRIS+ quadrotor UAS and measuring its energy consumption experimentally. The model is derived from the helicopter literature. Such models are required to create UAS flight planning systems.
This project purpose is aimed the A, the B, and the C models fan blades design, computational simulation, and discussion. The computational simulation effect of dust adhesion process. Therefore, the development of the surface hydrophobic film spraying methods can enhance the hydrophobicity to maintain the dust particles by the rotation of the blade on the surface slip and reduce the adhesion rate...
Unmanned and autonomous ground vehicles have the potential to revolutionize military and civilian navigation. Military vehicles, however, present unique challenges related to autonomous navigation that are not encountered in civilian applications. These include a high percentage of off-road navigation, navigation in hostile environments, navigation in GPS-denied environments, and navigation in urban...
Control of aerodynamic loads is a crucial issue in keeping wind energy economically competitive with traditional energy sources. This paper continues the investigation of the use of Iterative Learning Control (ILC) for load control in wind turbines with smart devices on rotor blades. A relatively simple computational fluid dynamics model is used to simulate the flow past an airfoil. Assuming no actuator...
A new high altitude propeller is analyzed and designed in this paper to be used on the stratospheric aircraft propulsion system. Two more appropriate approaches to investigate the aerodynamics characteristics of the high altitude propeller are obtained by comparison of vortex theory with the Spalart–Allmaras (S–A) model and XFOIL program, computational fluid dynamics (CFD), and wind tunnel tests,...
In most air cooled data centers the required air for cooling of IT equipment is supplied from a raised floor to server racks through perforated tiles; therefore, an understanding of tile impact on flow features is an essential step for designing an efficient air delivery scheme. In recent years, different approaches have been implemented to increase the efficiency of air delivery through tiles such...
The main objective of this research is to optimize the diffuser design of Diffuser Augmented Wind Turbine (DAWT). Specifically, this study investigates the effect of different shapes of diffusers to develop the suitable diffuser parameter for the wind turbine power enhancement. For that purpose, two diffuser cases have been recommended as an effective design in increasing wind speed, using a validated...
The rotor dimensioning of a wind turbine is essentially based on aerodynamic theory to define the parameters affecting its overall performance. The blade element momentum theory (BEM) has been widely used as a tool for the design of wind turbine blade. An existing airfoil shape with known chord and twist can be input to BEM to calculate the efficiency. On the other hand, if we set airfoil as unknown...
Autonomous flight of miniature UAVs demands high performance actuators satisfying the requirements of modern control algorithms. Specially for quadrotors, where lift and control forces are the result of a synchronized action of the four BLDC/propeller actuators, the form of their propellers are fundamental to attain a fast and reliable dynamic response. In this paper, we present a mathematical model...
This paper proposes a method to calculate the lift force of propeller using simulation software FLUENT. And on the basis of this, a certain degree of applicability of the formula from blade element theory is verified. It also presents suggestions for the analysis of the lift force of the propeller in the case of the impact of the incoming flow.
Online aero-engine washing is an advanced way to remove the compressor fouling, which is specified in the AMM (Aircraft Maintenance Manual). The effect of Aero-engine washing would be influenced by the characterization of liquid sheet. A numerical method is put forward to simulate the motion of liquid drop in the aero-engine when the particles enter into the front of the engine from nozzle. The study...
Compared with other lightning target on ground, the most notable feature of wind turbine is that the blade will normally be in a state of rotation during lightning strike. In order to study the specialty and mechanism of the influence of blade rotation on triggered lightning ability, the paper conducted some lightning discharge comparison tests under different status of stationary and rotating blade...
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