Aeronautical Engineering

Design and Optimization Method for Inertial Particle Separator Systems

by Eyas Alfaris

Helicopter aeroelastic analysis with spatially uncertain rotor blade properties

by Rajib Chowdhury

Aerospace Science and Technology, 16[1] (2012), pp. 29-39.

This paper investigates the effects of spatially uncertain material properties on the aeroelastic response predictions... more This paper investigates the effects of spatially uncertain material properties on the aeroelastic response predictions (e.g., rotating frequencies, vibratory loads etc.) of composite helicopter rotor. Initially, the spatial uncertainty is modeled as discrete random variables along the blade span and uncertainty analysis is performed with direct Monte Carlo simulations (MCS). Uncertainty effects on the rotating frequencies vary with the higher order modes in a non-linear way. Each modal frequency is found to be more sensitive to the uncertainty at certain sections of the rotor blade than uncertainty at other sections. Uncertainty effects on the vibratory hub load predictions are studied in the next stage. To reduce the computational expense of stochastic aeroelastic analysis, a high dimensional model representation (HDMR) method is developed to approximate the aeroelastic response as functions of blade stiffness properties which are modeled as random fields. Karhunen-Loeve expansion and a lower order expansion are used to represent the input and outputs, respectively, in the HDMR formulation which is similar to the spectral stochastic finite element method. The proposed method involves the approximation of the system response with lower dimensional HDMR, the response surface generation of HDMR component functions, and Monte Carlo simulation. The proposed approach decouples the computationally expensive aeroelastic simulations and uncertainty analysis. MCS, performed with computationally less expensive HDMR models, shows that spatial uncertainty has considerable influence on the vibratory hub load predictions.

Parametric study of manned aerocapture. I- Earth return from Mars

by Evans Lyne

Investigation of F5 Drag Chute Deployment

by Graeme Britton

Britton, G.A.; & Aw, L.C. 2007. Investigation of F5 Drag Chute Deployment, RSAF Aerospace Technology Conference, March, Singapore.

Long-Term Heat Treatments on Ti6Al4V-SiCf Composite. Part II-Mechanical Characterization

by Riccardo Donnini

- Materials Science Forum 604-605 (2009), pp. 341-350
- Co-authors: P .Deodati, R. Montanari, C. Testani, T. Valente

Micro-Chemistry and Mechanical Behaviour of Ti6Al4V-SiCf Composite Produced by HIP for Aeronautical Applications

by Riccardo Donnini

- Materials Science Forum Vol. 678 (2011), pp. 23-47
- Co-authors: P. Deodati, S. Kaciulis, M. Kazemian-Abyaneh, A. Mezzi, R. Montanari, C. Testani, N.Ucciardello

Micro-Chemistry and Mechanical Behaviour of Ti6Al4V-SiCf Composite Produced by HIP for Aeronautical Applications

by Riccardo Donnini

- Materials Science Forum Vol. 678 (2011), pp. 23-47
- Co-authors: P. Deodati, S. Kaciulis, M. Kazemian-Abyaneh, A. Mezzi, R. Montanari, C. Testani, N.Ucciardello

Nuclear Reactors Can Lift-Off Rockets

by C.AMARESHWAR PRASAD

Appreciated by 10 Researchers by Research Gate

Sir,

The highlights of the Project Idea in its abridged version speaks about the basic principles involved... more Sir,

The highlights of the Project Idea in its abridged version speaks about the basic principles involved in the working of a Nuclear Rocket with its hazard free smooth results and its light weight claiming lower cost of production.

The steam is generated using water and uranium. The performance evaluations calculated on Thrust force (steam) exhibited their enriched performance over conventional rocket. Perfect precautions and sufficient security can take care of successful mission giving fruitful results.

The total weight of rocket is nothing but its propellant weight, structural weight, and the pay load it carries. From the available sources of information cost of fuel for a nuclear rocket stands at 7.8 INR per liter which is very low compared to conventional fuel cost of 23.5 INR per liter. The quantum of fuel required is less and hence the structural weight compared to the conventional counterpart will be less. The weight of payload remains same for both. Hence the cost of production will be less.

Intelligence Algorithms for Increasing Navigation Systems Accuracy

by Mohamed Rahmouni

Application of neural network algorithm for increasing the accuracy of navigation systems are showing.
Various... more Application of neural network algorithm for increasing the accuracy of navigation systems are showing.
Various navigation systems, where a couple of sensors are used in the same device in different positions and the
disturbances act equally on both sensors, the trained neural network can be advantageous for increasing the
accuracy of system. The neural algorithm had used for determination the interconnection between the sensors
errors in two channels to avoid the unobservation of navigation system. Representation of thermal error of twocomponent navigation sensors by time model, which coefficients depend only on parameters of the device, its
orientations relative to disturbance vector allows to predict thermal errors change, measuring the current
temperature and having identified preliminary parameters of the model for the set position. These properties of
thermal model are used for training the neural network and compensation the errors of navigation system in nonstationary thermal fields.