Numerical Simulation on Shoreline Change in Western Region of Badung Regency, Bali, Indonesia

Shoreline change is considered the most dynamic processes in coastal region. Coastal erosion is a global problem where 70% beaches around the world are recessional. Almost all coastal area in Bali is potential to suffer from erosion. Badung Regency in Bali has many beaches that famous as tourism area where from about 64 km shoreline length, 11,5 km were recorded suffered by erosion in 1985 and 12,1 km erosion in 2007. This study aims to determine the value of shoreline changes that occur in western of Badung Regency from 2001 to 2010 based on the predicted wave data using monthly wind data from Ngurah Rai, Tuban, Badung, Bali meteorological station. Shoreline change simulation measured the forward (accretion) or backward (erosion) distance of the shoreline on the East-West direction. Bali has wind patterns that influenced by the Northwest monsoon from November-April and Southeast monsoon from May-October. In 2001-2010, dominant wind in this region was coming from east, southeast, and west. Geographically western coast of Badung influenced by incoming winds from the west, southwest, and south. Wind blow towards the coast in 2001-2010 are dominantly come from the west with wind speed range was about 1,7-4,7 m/s. Simulation indicated that generally shoreline tends to experience accretion in the north and erosion in the south. From 16000 m of study shoreline, along 7100 m of shoreline tend to suffer by erosion. Oppositely, along 8900 m of shoreline tend to have accretion

Numerical simulation of convective airflow in an empty room

Numerical simulation of airflow inside an empty room has been carried out for a forced convection, a natural convection and a mixed convection respectively, by using a computational fluid dynamics approach of solving the Reynolds-averaged Navier-Stokes fluid equations. Two-dimensional model was studied at first; focusing on the grid refinement, the mesh topology effect, and turbulence model influences. It was found that structured mesh results are in better agreement with available experimental measurements for all three scenarios. Further study using a three-dimensional model has shown very good agreements with test data at measuring points. Furthermore, present studies have revealed low-frequency flow unsteadiness by monitoring the time history of flow variables at measuring positions. This phenomenon has not yet reported and discussed in previous studies

Numerical Aerodynamic Simulation

An overview of historical and current numerical aerodynamic simulation (NAS) is given. The capabilities and goals of the Numerical Aerodynamic Simulation Facility are outlined. Emphasis is given to numerical flow visualization and its applications to structural analysis of aircraft and spacecraft bodies. The uses of NAS in computational chemistry, engine design, and galactic evolution are mentioned

Numerical Simulation for Scenario Based Volcanic Hazard Assessment (VHA) at Seulawah Agam Volcano, Aceh, Sumatra

Seulawah Agam is an active volcano with high 1,810 m located at 5.448°N 95.658°E and close to the capital of Aceh province densely populated. Following Sumatra-Andaman earthquake 26 December 2004, Sumatra Island has increased not only seismicity but also volcanic activity. On the other hand, Sinabung volcano categorized as inactive volcano, but beyond expectations on the 3rd September 2010 experienced eruption and the closest volcanic eruption location to Seulawah Agam volcano. Meanwhile, in 1 September 2010, Seulawah Agam categorized as active volcano was alert to level 2. We cannot predict what happens in future to the Seulawah Agam volcano, but we can provide volcano hazard assessment as important step for mitigation procedure. This paper introduces numerical study for volcanic eruption and integrated with a GIS-based tool for volcanic hazard assessment VORIS (VOlcanic Risk Information System) which develop by Alicia Felpeto. This model investigate scenario based volcanic eruption for ash fallout, PDC (pyroclastic density currents), and lava. Digital elevation model (DEM) from SRTM (Shuttle Radar Topography Mission), meteorological data from NOAA, and geological study are used in this model. In the statovolcano mountain four geothermal manifestations appeared, such as: Fumarol Simpago, crater Heutz, ground steam Ie-Jue, and hot spring Ie-Suum. In this numerical simulation, we consider the location as potential eruption vent to produce erupted material. Wind velocity data at 3rd January 2012 and 1 July 2012 above the summit is selected to represent wet and dry season condition for scenario based ash fallout. Further, the simulation show the ash fallout is possible to reach Banda Aceh and potentially disrupt flight at Sultan Iskandar Muda Air port. Lava flow simulations are only depending on topography data (DEM) and applying some parameter for maximum flow length 5 km. The Simulation resolution depend on DEM data (90m) which produce more precise then volcanic hazard map produce by Center of Volcanology and Geological Hazard Mitigation, Bandung (CVGHM) and more reasonable with topography slope of mountain at southern part and northern part. Furthermore, PDC simulations are conducted scenario for height eruption column (starting point of the flow) 20m dan 200m. The simulations show PDC can be reach longer location until Banda-Aceh Medan Highway compare then CVGHM map. This preliminary research should be developed to apply high resolution DEM and using adequate method for estimation eruption parameters. This method will be potential to provide more precise volcano hazard assessment for others volcano in Indonesi

Numerical simulation of biodiversity: comparison of changing initial conditions and fixed length of growing season

This study examined the effect of varying the initial value of industrialization for a fixed length of growing season on the prediction of biodiversity loss. We have found that when the initial value of industrialization is 0.1 under a shorter length of growing season, a relative low due of biodiversity loss can be maintained. The biodiversity loss value can be further lowered by maintaining the same length of growing season but with a reduced initial value of industrialization to 0.01 or 0.02. We would expect this alternative result to provide a further insight into our fight against biodiversity loss which has both human and sustainable development devastating effects

Numerical Simulation of the Deformation of Some MEMS

In this paper we present the numerical simulation of the deformation of two Micro-Electromechanical Systems (MEMS), a trampoline-type one i.e. a rectangular cantilever beam and an accelerometer that consists of a square plate with all edges simply supported. The deformation of these systems is modeled by fourth-order differential equations, ordinary and partial respectively. We find the approximate solutions by using the finite differences method programmed in Matlab, solving the system of linear equations associated with different methods to evaluate the efficiency of these. We obtained very good approximations with small errors compared to other articles that use other approaches

Numerical simulation of prominence oscillations

We present numerical simulations, obtained with the Versatile Advection Code, of the oscillations of an inverse polarity prominence. The internal prominence equilibrium, the surrounding corona and the inert photosphere are well represented. Gravity and thermodynamics are not taken into account, but it is argued that these are not crucial. The oscillations can be understood in terms of a solid body moving through a plasma. The mass of this solid body is determined by the magnetic field topology, not by the prominence mass proper. The model also allows us to study the effect of the ambient coronal plasma on the motion of the prominence body. Horizontal oscillations are damped through the emission of slow waves while vertical oscillations are damped through the emission of fast waves.Comment: 12 pages, 14 figures, accepted by Astronomy and Astrophysic

Numerical simulation of spreading drops

We consider a liquid drop that spreads on a wettable surface. Different time evolutions have been observed for the base radius r depending of the relative role played by inertia, viscosity, surface tension and the wetting condition. Numerical simulations were performed to discuss the relative effect of these parameters on the spreading described by the evolution of the base radius r(t) and the spreading time tS. Different power law evolutions r(t) ∝ tⁿ have been observed when varying the parameters. At the early stage of the spreading, the power law t½ (n = 1/2) is observed as long as capillarity is balanced by inertia at the contact line. When increasing the viscosity contribution, the exponent n is found to increase despite the increase of the spreading time. The effect of the surface wettability is observed for liquids more viscous than water. For a small contact angle, the power law t½ is then followed by the famous Tanner law t1/10 once the drop shape has reached a spherical cap

Numerical simulation of Faraday waves

We simulate numerically the full dynamics of Faraday waves in three dimensions for two incompressible and immiscible viscous fluids. The Navier-Stokes equations are solved using a finite-difference projection method coupled with a front-tracking method for the interface between the two fluids. The domain of calculation is periodic in the horizontal directions and bounded in the vertical direction by two rigid horizontal plates. The critical accelerations and wavenumbers, as well as the temporal behaviour at onset are compared with the results of the linear Floquet analysis of Kumar and Tuckerman [J. Fluid Mech. 279, 49-68 (1994)]. The finite amplitude results are compared with the experiments of Kityk et al. [Phys. Rev. E 72, 036209 (2005)]. In particular we reproduce the detailed spatiotemporal spectrum of both square and hexagonal patterns within experimental uncertainty