Congrès International d'Architecture Moderne

About: Congrès International d'Architecture Moderne is a based out in . It is known for research contribution in the topics: Boundary value problem & Jet (fluid). The organization has 393 authors who have published 403 publications receiving 4104 citations.

Numerical Investigations of Tonal Noise of Counter-Rotating Open Rotors:

Abstract: In the work are presented the results of a three dimensional computational analysis of tonal noise of two counter-rotating open rotors. The analysis was performed using 3DAS (3 Dimensional Acoustics Solver) CIAM in-house solver, designed for three dimensional calculation of turbomachinery tone noise generation, propagation and radiation in the near and the far acoustic fields. The results of the computations were compared with the results of experiments performed in the wind tunnel of Central Aerohydrodynamic Institute (TsAGI), Russia, within the project DREAM (Validation of radical engine architecture systems) of European Seventh Framework Programme (FP7). The comparison showed satisfactory correspondence between directivity diagrams for the tone noise on combinational harmonics.

Investigation of the photochemical behaviour of pyrethroids lacking the cyclopropane ring by photo-solid-phase microextraction and gas chromatography/mass spectrometry.

Abstract: The characterization of by-products arising from the UV photodegradation of two insecticide pyrethroids lacking the cyclopropane ring (flucythrinate and fenvalerate) has been investigated by gas chromatography coupled with mass spectrometry (GC/MS). Twenty photoproducts were tentatively identified mainly based on the interpretation of the experimental mass spectra or by using reference mass spectra. Some of these compounds had not previously been detected. Furthermore, the generation of some of the photoproducts might be a matter for concern due to their potential toxicity. The corresponding photodegradation routes, including postulation of the intermediate radicals, have also been proposed. These photodegradation studies were performed by photo-solid-phase microextraction (photo-SPME) in which the SPME fibre was exposed to light after extraction of the target analytes from aqueous solutions. The degradation kinetics of the investigated pyrethroids and the photoformation-photodegradation curves of the photoproducts generated in situ were also monitored through the ion chromatograms obtained for different irradiation times and the corresponding mass spectra.

Application of taguchi's design of experiment in performance analysis of destination sequence distance vector (DSDV) routing protocol in mobile ad hoc networks

Abstract: Numerous routing protocols for mobile ad hoc networks (MANETs) have been designed in process information delivery from a source node to a destination node. In this paper, the Taguchi's design of experiment (TDE) has been applied to investigate the performance of Destination Sequence Distance Vector (DSDV) routing protocol in MANETs. The effects of network parameters namely terrain sizes, node speeds, network sizes, transmission ranges, transmission rates, pause times and the number of maximum connections on packet delivery ratio and routing overhead in medium scale ad hoc networks have been done through simulation experiments. Through this study, we can rank these factors that may affect packet delivery ratio and routing overhead. The response performance was analyzed based on signal-to-noise ratio and analysis of variance (ANOVA). The results revealed that the transmission range was the most influential factor on the packet delivery ratio, followed by terrain size and transmission rate. The network size had the greatest effect on routing overhead, followed by the transmission range.

Development challenges of distributive propulsion systems for advanced aeroplanes

Abstract: Purpose – This paper aims to consider main challenges of development of advanced architectures of propulsion systems, i.e. distributed propulsion systems (DPS). Design/methodology/approach – This paper is a comparative analysis of different types of DPS. Findings – Mechanical driving DPS seems as more feasible in near-term outlook, and turboelectric and full electric DPS are imagined feasible in mid- and far-term outlook. Research limitations/implications – Additional comprehensive numerical and experimental researches are needed to approve the efficiency of DPS. Practical implications – Possible impact of installation of DPS on aeroplane fuel efficiency are shown. Originality/value – Application of DPS on long-range aeroplanes is new a engineering solution, which may allow to meet future advanced efficiency goals.

Solving a mixed boundary value problem via an integral equation with adjoint generalized Neumann kernel in bounded multiply connected regions

Abstract: In this paper, we solve the mixed boundary value problem on bounded multiply connected region by using the method of boundary integral equation. Our approach in this paper is to reformulate the mixed boundary value problem into the form of Riemann-Hilbert problem. The Riemann-Hilbert problem is then solved using a uniquely solvable Fredholm integral equation on the boundary of the region. The kernel of this integral equation is the adjoint generalized Neumann kernel. As an examination of the proposed method, some numerical examples for some different test regions are presented.