^{3rd International Conference and Exhibition on} Mechanical & Aerospace Engineering October 05-07, 2015 San Francisco, USA

Soon-Duck Kwon has 20 years experiences on windtunnel tests and bridge aerodynamics after completing hisPhD from Seoul National University in Korea.He is currently director of the KOCED Wind Tunnel Center in Chonbuk National University, Korea.

The effect of blockage ratio on wind tunnel testing of small vertical-axis wind turbines has been quantitatively investigated in this study. Darrieus type three blades vertical axis wind turbine was used in the wind tunnel tests. Height and rotor diameter of the turbine were 0.4m and 0.35m respectively. We measured the wind speeds and power coefficients at three different wind tunnels where blockage ratio were 3.5%, 13.4% and 24.7% respectively. The test results show that the measured powers have been strongly influenced by the blockage ratio and the rotor tip speed ratio. The power coefficients generally increase as the blockage ratio and tip speed ratio increases. The power coefficient at blockage ratio of 24.7% reveals two times greater than that at 3.5%. After examining various blockage correction methods, the most of the correction methods are found to be unsuitable for Darrieus wind turbines. The correction methods which use wind velocity drop ratio underestimate the blockage effect, yet the conventional Maskell’s correction method overestimate the blockage effect. Maskell method is basically applicable to the rectangular solid body but the Darius rotor is not a solid body but a porous one. Therefore the present study proposed the modified correction coefficients for the Darrieus wind turbine based on the measurements. The results show that the correction error for power coefficients can be less than 5% when the present correction coefficients apply.

Fatemeh Amiri is doing her Ph.D at Bauhaus university of Weimar, Germany. She has completed her Master of Applied Mathematics at the age of 25 years from Isfahan University of Technology. She has published two papers in fracture mechanics field with Prof. Timon Rabczuk and Prof. Marino Arroyo.

The prediction of fracture in thin structures is of major importance in engineering applications such as aircraft fuselages, pressure vessels, automobile components, and castings. Since analytical solutions provide limited information, there has been a keen interest in numerically simulating fracture in thin shells in recent years. However, despite the advances made in modeling fracture for solid bodies fracture in thin bodies remains a challenge due to the complex interplay between cracks and the shell kinematics and geometry. We present a phase-field model for fracture in Kirchoff-Love thin shells using the local maximum- entropy (LME) meshfree method. Since the crack is a natural outcome of the analysis it does not require an explicit representation and tracking, which is advantage over techniques as the extended finite element method that requires tracking of the crack paths. The geometric description of the shell is based on statistical learning techniques that allow dealing with general point set surfaces avoiding a global parameterization, which can be applied to tackle surfaces of complex geometry and topology. This topic is of high relevance for real-world applications, for example in the automotive industry and in aerospace engineering.

Joaquin Azcue completed his B.S. Degree in Mechanical engineering in 1998 at Parks Collage of Saint Louis University. He is one of the Mechanical engineers of the GISCU laboratory at the Spanish National Aerospace Institute for the past nine years, performing tasks in the areas of mechanical design, integration and tests of payloads. Over the past three years he has been in charge of the design group of the cryogenic filter wheel for the SAFARI instrument on the ESA/JAXA SPICA mission. Before he has also work as structural engineering for Tecnicas Reunidas at Madrid, Spain.

The MetNet MMPM Mission is implemented in collaboration with Finnish Meteorological Institute (FMI), Lavochkin Association, Russia (LA), Russian Space Research institute (IKI) and Instituto Nacional de Tecnica Aeroespacial, Spain (INTA). MetNet in situ observation lander mission for Martian atmospheric science is based on a new semihard landing vehicle called the MetNet Lander (MNL). The MNL will have a versatile science payload focused on the atmospheric science of Mars. INTA has developed two units for this mission the Tri-axial magnetometer (MOURA) that is located on the top of the outer part of the inflatable breaking unit and the Solar Irradiation Sensor (MetSIS) that will be placed on top of the MetNet Lander extensible boom. The Solar Irradiance Sensor is equipped with wireless optical communication capabilities. The first terminal (OWLS-MetSIS-I), is situated in the bottom of the Solar Irradiance sensor. The second terminal of the wireless communication system is placed on the base of the meteorological boom. The Units are going to be mounted on a penetrator type of lander that will reach Martian surface at a speed of 200 km/h. This impact introduces shock loads of 500 g during 15-20 ms. One of the main challenges for the qualification of the units was to develop a testing facility able to reproduce the shock levels suffered by the different units on the landing stage. A testing facility was developed at INTA by using a modified air pressure cannon, a deceleration chamber is mounted on the tip of the cannon. The units are mounted on a polystyrene bullet, a housing for the units is performed on the bullet. There is also mounted on the bullet an electronic board with an accelerometer and a memory to record the data for each impact test. Each of the units was successfully tested on this facility achieving the required shock levels.

Valvanera Eiriz Martinez has completed her studies in 2005 in Physics specializing in Material Physics at the Universidad Complutense de Madrid (Spain). She started her professional activities working as Optical engineer at LINES (Space Instrumentation Laboratory) at INTA performing optical characterization test, alignment test and integration and test procedures for different optical subsystems for the MIRI-MTS project (James Webb Space Telescope). At present she is working at GISCU (payload engineering group) belonging to INTA (Spanish National Institute of Aerospace Technology) working as AIVT (Assembly, Integration, Verification and Test) engineer for ASIM-MXGS project.

INTA is a partner of the Spanish consortium on the MXGS (Modular X-Ray and Gamma-Ray Sensor) Instrument, part of the ASIM (Atmospheric Space Interactions Monitor) ESA Mission to be assembled on the Columbus Module of the ISS (International Space Station). MXGS is designed to detect Terrestrial Gamma Flashes (TGF) due to high energy phenomena in the upper atmosphere layers, which sources and physics are the mission objectives. Low and Medium energy detectors with space heritage (two detectors assemblies, one with CZT and another of BGO detectors), and a code mask at front of the instrument, provide imaging capabilities for TGF location. All instrument subsystems are mounted in the mechanical housing. A variable environment due to the ISS orbit and attitudes, with tight temperature requirements, are challenging the instrument thermal control. Mass and envelope budget are the constraints for the structural, integration, tests and verification activities. During Phases C/D, INTA is responsible for the Product Assurance (PA) on the Spanish contribution; Assembly, Integration, Verification and Test (AIVT) activities for the MXGS STM (Structural Thermal Model) and PFM (Proto Flight Model) models; the Thermal Control Subsystem development; and also participates in the Scientific Program definition. The Payloads and Instrumentation Area at INTA has designed a thermal control subsystem based on passive and active thermal control systems. The Passive Thermal Control System consists of LHP (Loop Heat Pipes), AGHP (Axial Groove Heat Pipes), coating finish, MLI (Multi Layer Insulation) for radiative insulation, Titanium thermal washers for conductive insulation and radiators. The Active Thermal Control System is composed of heaters, thermostats and thermal sensors. Some conclusions from the thermal analysis are shown, together with test results of the LHP Technological Model developed during the Phase B studies, and the advantages of such kind of thermal design.

Merouane Salhi was born in Blida-ALGERIA, on March 19th, 1985. He enrolled at the Institute of Aeronautics and Space Studies at Blida University in 2002. In 2007, he earned a State Engineer degree in Aeronautical Propulsion. When he enrolled at the same institute, in 2010, SALHI earned his Magister in Aeronautical Engineering. He joined COSIDER GROUP in 2010, becoming a Mechanical Engineer; he stayed in that position six months, after that he joined the Institute of Aeronautics and Space Studies at Blida 1 University in 2011. He became an Assistant Professor of Aerodynamics and Propulsion until now. He also served as an affiliate member of the Aeronautical Sciences Laboratory at Blida University. SALHI works on Aerodynamics and propulsion systems. He also teaches Mathematics, Mechanics, Electricity, Vibrations and waves, Materials Resistance and Aerodynamics at Blida University. He has some publications on aerodynamics and nozzle.

When the stagnation pressure of a perfect gas increases, the specific heat and their ratio do not remain constant anymore and start to vary with this pressure. The gas doesn’t remain perfect. Its state equation change and it becomes for real gas. In this case, the effects of molecular size and intermolecular attraction forces intervene to correct the state equation. The aim of this work is to show and discuss the effect of stagnation pressure on supersonic thermodynamically, physical and geometrical flow parameters, to find a general case for real gas. With the assumptions that Berthelot’s state equation accounts for molecular size and intermolecular force effects, expressions are developed for analyzing supersonic flow for thermally and calorically imperfect gas lower than the dissociation molecules threshold. The designs parameters for supersonic nozzle like thrust coefficient depend directly on stagnation parameters of the combustion chamber. The application is for air. A computation of error is made in this case to give a limit of perfect gas model compared to real gas model.