Showing papers by "Vallam Sundar published in 2007"

Runup and Inundation along the Indian Peninsula, Including the Andaman Islands, due to Great Indian Ocean Tsunami

Abstract: The December 2004 Sumatra earthquake triggered massive tsunami waves in the Indian Ocean and the Bay of Bengal. The tsunami waves traveled primarily in the east-west direction and caused major damage along the coasts of southern India, Sri Lanka, Thailand, and Indonesia. It has proved to be the most disastrous tsunami in recorded history, and scientists and engineers around the world set out to record signatures of the tsunami from which the characteristics of the tsunami waves at the time of landfall could be deciphered. Such information is extremely useful in validating mathematical models for understanding the characteristics of tsunamis and their effects along the coast. The writers conducted surveys along the east and west coasts of peninsular India—focusing on the states of Tamil Nadu and Kerala and around Andaman and Nicobar Islands, where the devastation caused by the tsunami was unparalleled. The analysis of data gathered during the post-sunami survey focused on consolidating the primary paramete...

Physical model studies on discus buoy in regular, random and double peak spectral waves

Abstract: An experimental investigation was carried out to study the motion characteristics of a data buoy under regular as well as uni-modal and bimodal sea states. For the present study, the 2.2 m diameter discus shaped data buoy of India’s National Data Buoy Programme (NDBP) was scale modeled and, its heave and pitch motions were measured by two methods using potentiometers and motion capturing non contact infra-red cameras. The response amplitude operators obtained through the present experiment are proved to be predicting the different ranges of sea states well. The details of the model, instrumentation, testing conditions and the response amplitude operators for heave and pitch as a function of excitation frequency are presented and discussed in this paper.

Modeling of the Indian Ocean Tsunami

Abstract: Shallow Water Equations are solved using an Unstructured Explicit Finite Element Method (UEFEM) to simulate long waves in the ocean. The formulation of the UEFEM has been described and found to be computationally efficient for large problems such as basin level modeling of tsunamis. Different domains have been considered to simulate the propagation of the waves due to an artificially imposed initial disturbance. The domain of Bay of Bengal has been considered for simulation with an initial disturbance which resembles the type and location of the 2004 Indian Ocean Tsunami. The Wave elevation and deformations as well as time of travel of tsunami are reproduced. The method hence has high potential of being attractive for application of simulation of global tsunamis.Copyright © 2007 by ASME

Experimental and numerical studies on the tsunami wave characteristics

Abstract: The devastating effects of the great Indian ocean tsunami has forced researchers in focusing their attention more vigorously on understanding the behaviour during its propagation and its effects on structures. This can obviously be accomplished through numerical and physical model studies or combination of both. The characteristics of a tsunami wave can approximately be same as that of a solitary wave which is basically a shallow water wave. Hence, the studies on the characteristics of shallow water waves have become an emerging topic of interest. An important aspect of a mitigation effort is to predict the tsunami wave kinematics. A combination of experimental and numerical simulation of tsunami represented by the solitary wave was studied and their comparison is discussed in this paper. The details of the numerical approach, methodology, instrumentation and measurement adopted for the present study are reported. The disagreement of the experimental simulation of solitary wave elevations with th...