Topology and grid adaption for high-speed flow computations

This study investigates the effects of grid topology and grid adaptation on numerical solutions of the Navier-Stokes equations. In the first part of this study, a general procedure is presented for computation of high-speed flow over complex three-dimensional configurations. The flow field is simulated on the surface of a Butler wing in a uniform stream. Results are presented for Mach number 3.5 and a Reynolds number of 2,000,000. The O-type and H-type grids have been used for this study, and the results are compared together and with other theoretical and experimental results. The results demonstrate that while the H-type grid is suitable for the leading and trailing edges, a more accurate solution can be obtained for the middle part of the wing with an O-type grid. In the second part of this study, methods of grid adaption are reviewed and a method is developed with the capability of adapting to several variables. This method is based on a variational approach and is an algebraic method. Also, the method has been formulated in such a way that there is no need for any matrix inversion. This method is used in conjunction with the calculation of hypersonic flow over a blunt-nose body. A movie has been produced which shows simultaneously the transient behavior of the solution and the grid adaption

Grid adaption for bluff bodies

Methods of grid adaptation are reviewed and a method is developed with the capability of adaptation to several flow variables. This method is based on a variational approach and is an algebraic method which does not require the solution of partial differential equations. Also the method was formulated in such a way that there is no need for any matrix inversion. The method is used in conjunction with the calculation of hypersonic flow over a blunt nose. The equations of motion are the compressible Navier-Stokes equations where all viscous terms are retained. They are solved by the MacCormack time-splitting method and a movie was produced which shows simulataneously the transient behavior of the solution and the grid adaptation. The results are compared with the experimental and other numerical results

Climate Variability and Rice Production in North India: A Review

Variability in climatic factors is one of the main determinants of agriculture production. Past agrarian studies have shown that variability in rainfall and temperature has decline agriculture production in entire North Indian States. Farmers, especially small and marginal are adversely affected from climate variability. They have less resources and coping strategies against the climatic variability. Rice is the one of important crop for all North Indian State’s people. Level of temperature already reaches to tolerance level of crops and it is increasing day by day. Also variability in rainfall during Kharif cropping season has been reported in all North Indian states. Incidence of extreme climatic events such as drought and flood is also repeated in these areas. Level of carbon dioxide is also increased due to over exploitation of natural resources and industrial activities in these states. Growth in population is much higher in last three decades. So burden on natural resources such as on agriculture is becoming very high. Agriculture sector needs immediate action against climate variability. Mitigation strategies are time taking process. However, an adaptation method is best technique to mitigate consequences of climate variability. Sowing date and use of technological tools are the best adaptive method to minimize the impact of climate variability

Prevention of Conflict-Induced IDPs and Their Protection: The Challenges

Displacement due to war, protracted conflicts, mass violation of human rights, generalised violence, repression of minorities, natural and technological disasters has been a matter of concern. However, displacement due to the intensified armed conflicts and violence has become a common phenomena around the world and remains a critical factor of vulnerability for people across the world. Displacement also creates logistical and humanitarian nightmare, and threatens international security and risks the lives of displaced people, aid workers, and peacekeepers. In this context, the paper attempts to identity the reasons of initial neglect for the international community. Furthermore, the trends in conflict-induced displacement and the challenges confronting the international community in protection and prevention of conflict-induced IDPs is examined

China’s Footprints in Maldives: Concern for India?

China has, in the recent decades, has consolidated its interests in the South Asian region. This change in China’s foreign policy, from a focus on the North-East and South-East Asia, hints at an attempt to sustain China’s own peaceful rise. India, on the other hand, has emphasised on a ‘Look East’ foreign policy in the recent times. Both India and China share an important diplomatic relationship with Maldives. However, China’s growing influence in Maldives might be a serious strategic concern to India. This article is an exploratory study of the relationship that China shares with Maldives and its implications to India