C201 Evaluation of tsunami run-up on land with three-dimensional fluid simulation

A three-dimensional two-way coupled fluid-sediment interaction model (FSM) is applied to investigate run-up tsunami deformation and tsunami force acting on square structures on land. The FSM consists of a generalized Navier-Stokes solver (GNS) for multi-phase flow including porous flow, a volume of fluid module (VFM) for air-water interface tracking, and a sediment transport module (STM) for fluid-sediment interface tracking. In the FSM, a two-way coupling procedure is implemented at each time step to connect the GNS with the VFM and the STM. The predictive capability of the FSM is demonstrated through comparison between numerical results and experimental data in terms of water surface elevation, inundation depth, and tsunami force. The process of tsunami run-up in the presence of square structures is investigated in terms of vortex structures. The result shows that the FSM is a useful tool providing detailed information in discussing run-up tsunami deformation and tsunami force.

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DIFFERENCES ON DIFFERENT FIDELITY LEVEL IN MODELING OF BUILDING AND EMBANKMENT HEIGHT ON TSUNAMI RUN UP SIMULATION BY 2D FINITE DIFFERENCE METHOD

Journal of Japan Society of Civil Engineers Ser A1 (Structural Engineering & Earthquake Engineering (SE/EE)) ◽

10.2208/jscejseee.74.i_1052 ◽

2018 ◽

Vol 74 (4) ◽

pp. I_1052-I_1061

Author(s):

Naoki NAKAYA ◽

Mitsuteru ASAI ◽

Toshitaka BABA ◽

Shota MASAGAKI

Keyword(s):

Finite Difference ◽

Finite Difference Method ◽

Difference Method ◽

Fidelity Level ◽

Embankment Height ◽

Run Up ◽

Tsunami Run Up

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Shoreline Changes along Northern Ibaraki Coast after the Great East Japan Earthquake of 2011

Remote Sensing ◽

10.3390/rs13071399 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1399

Author(s):

Quang Nguyen Hao ◽

Satoshi Takewaka

Keyword(s):

Near Infrared ◽

Thermal Emission ◽

Sandy Beaches ◽

Great East Japan Earthquake ◽

Shoreline Changes ◽

Run Up ◽

Tsunami Run Up ◽

Sentinel 2 ◽

Infrared Radiometer

In this study, we analyze the influence of the Great East Japan Earthquake, which occurred on 11 March 2011, on the shoreline of the northern Ibaraki Coast. After the earthquake, the area experienced subsidence of approximately 0.4 m. Shoreline changes at eight sandy beaches along the coast are estimated using various satellite images, including the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer), ALOS AVNIR-2 (Advanced Land Observing Satellite, Advanced Visible and Near-infrared Radiometer type 2), and Sentinel-2 (a multispectral sensor). Before the earthquake (for the period March 2001–January 2011), even though fluctuations in the shoreline position were observed, shorelines were quite stable, with the averaged change rates in the range of ±1.5 m/year. The shoreline suddenly retreated due to the earthquake by 20–40 m. Generally, the amount of retreat shows a strong correlation with the amount of land subsidence caused by the earthquake, and a moderate correlation with tsunami run-up height. The ground started to uplift gradually after the sudden subsidence, and shoreline positions advanced accordingly. The recovery speed of the beaches varied from +2.6 m/year to +6.6 m/year, depending on the beach conditions.

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Run-Up Simulation of a Semi-Floating Ring Supported Turbocharger Rotor Considering Thrust Bearing and Mass-Conserving Cavitation

Lubricants ◽

10.3390/lubricants9040044 ◽

2021 ◽

Vol 9 (4) ◽

pp. 44

Author(s):

Christian Ziese ◽

Cornelius Irmscher ◽

Steffen Nitzschke ◽

Christian Daniel ◽

Elmar Woschke

Keyword(s):

Reynolds Equation ◽

Energy Equation ◽

Thrust Bearing ◽

Three Dimensional ◽

Reliable Prediction ◽

Two Phase ◽

Hydrodynamic Bearings ◽

Thrust Bearings ◽

Run Up ◽

The Impact

The vibration behaviour of turbocharger rotors is influenced by the acting loads as well as by the type and arrangement of the hydrodynamic bearings and their operating condition. Due to the highly non-linear bearing behaviour, lubricant film-induced excitations can occur, which lead to sub-synchronous rotor vibrations. A significant impact on the oscillation behaviour is attributed to the pressure distribution in the hydrodynamic bearings, which is influenced by the thermo-hydrodynamic conditions and the occurrence of outgassing processes. This contribution investigates the vibration behaviour of a floating ring supported turbocharger rotor. For detailed modelling of the bearings, the Reynolds equation with mass-conserving cavitation, the three-dimensional energy equation and the heat conduction equation are solved. To examine the impact of outgassing processes and thrust bearing on the occurrence of sub-synchronous rotor vibrations separately, a variation of the bearing model is made. This includes run-up simulations considering or neglecting thrust bearings and two-phase flow in the lubrication gap. It is shown that, for a reliable prediction of sub-synchronous vibrations, both the modelling of outgassing processes in hydrodynamic bearings and the consideration of thrust bearing are necessary.

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NEAR-FIELD TSUNAMI FORECASTING BASED ON A TSUNAMI RUN-UP RESPONSE FUNCTION

Coastal Engineering Proceedings ◽

10.9753/icce.v36v.currents.5 ◽

2020 ◽

pp. 5

Author(s):

Juh-Whan Lee ◽

Jennifer L. Irish ◽

Robert Weiss

Keyword(s):

Real Time ◽

Response Function ◽

Near Field ◽

Coastal Communities ◽

Tsunami Forecast ◽

Earthquake Fault ◽

Tsunami Forecasting ◽

Fault Parameters ◽

Run Up ◽

Tsunami Run Up

Since near-field-generated tsunamis can arrive within a few minutes to coastal communities and cause immense damage to life and property, tsunami forecasting systems should provide not only accurate but also rapid tsunami run-up estimates. For this reason, most of the tsunami forecasting systems rely on pre-computed databases, which can forecast tsunamis rapidly by selecting the most closely matched scenario from the databases. However, earthquakes not included in the database can occur, and the resulting error in the tsunami forecast may be large for these earthquakes. In this study, we present a new method that can forecast near-field tsunami run-up estimates for any combination of earthquake fault parameters on a real topography in near real-time, hereafter called the Tsunami Run-up Response Function (TRRF).Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/tw1D29dDxmY

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