Assessment of performance of interpolation methods for temporal resolution of wind data on wave modelling

Download
2019
Ak, Gülçe Hazal
In this thesis, the performance of different interpolation techniques for wind hindcasting have been assessed and a computer model based study have been performed on its effects on wave hindcasting. Climate Forecast System Reanalysis (CFSR) dataset between 1979 and 2010 is used for long term time series analysis and extreme event analysis in Black Sea region. The aims are to obtain new dataset using the existing dataset, to determine the reliability of statistical analysis of winds and to evaluate the error margins in numeric wave models. W61, a parametric wave hindcasting model has been used for long term and extreme wave analysis and WAVEWATCH III has been used for further analysis of 3 extreme events within the Black Sea. Several statistical parameters are used to evaluate and compare the interpolation methods including Mean Absolute Error, Coefficient of Variation Root Mean Square Error and Normalized Bias. The wave and statistical analysis results indicated that the performances of the interpolation methods for wave analysis are not compatible with the wind analysis results. Also, performances of the interpolation methods varies through the analyzed 25 points within the Black Sea for both long term and extreme wave analysis.

Suggestions

Influence wave mode computations of multi-passage cascade flows
Tuncer, İsmail Hakkı (2000-01-01)
Copyright © 2000 by ASME.A Navier-Stokes solution method with overset grids is employed to compute the Influence Wave Modes of a compressor cascade in transonic flow conditions. The computed predictions are compared against the experimental data and the predictions based on Traveling Wave Mode computations performed using a different Navier-Stokes solver. In the present method, a five-passage flow domain is discretized with O-type subgrids around each blade and a rectangular background subgrid, A simple, ro...
2D phase-field simulation and experimental validation of droplet formation in a flow-focusing junction
Atik, Ali Can; Yıldırım, Ender; Külah, Haluk (null; 2020-10-04)
In this study, we investigated the performance of 2D simulations to predict the droplet sizes under varying flow conditions. Simple 2D models are lacking in presenting correct results because the top and bottom wall boundaries are excluded despite their significant effect on the flow construction. Here, we added an extra drag term representing the pressure drop due to the resistance of these boundaries to the Navier-Stokes equation. We compared the modified 2D model with the 3D model and experimental data, ...
Analysis of the peak position and linewidth as a function of temperature for the phase transitions in LiKSO4
Yurtseven, Hasan Hamit (World Scientific Pub Co Pte Lt, 2016-02-20)
Analysis of the peak position and the linewidths of various infrared modes is performed at high (300-850 K) and low (1.5-300 K) temperatures using the experimental data from the literature for LiKSO4 which exhibits a sequence of phase transitions. The temperature dependences of the frequency and the linewidth which are derived from the anharmonic self-energy are fitted to the observed peak positions and the linewidths of the S-O stretching modes (internal nu(3) modes at 1135 cm(-1) and at 1180 cm(-1)), peak...
Predictions on absorption and scattering characteristics of acoustic scatterers modified with micro-perforated panels
Odabaş, Erinç; Çalışkan, Mehmet; Department of Mechanical Engineering (2012)
In this study, the basic absorption and scattering characteristics of acoustic scatterers, specifically Schroeder Diffusers, are investigated. Schroeder Diffusers are one of the most widely used acoustic scatterers in which the scattering phenomenon is predictable due to the geometry of the diffuser, based on a particular mathematical sequence. It is shown that it is possible to increase the amount of absorption by modifying the diffuser structure by means of adding perforated panels into the wells or narro...
Experimental characterization of a tuned vibration absorber
Aksoy, Tuğrul; Özgen, Gökhan Osman; Acar, Bülent; Gençoğlu, Caner (2016-01-01)
In this paper, experimental characterization studies conducted for a tuned vibration absorber is presented. The tuned vibration absorber has been particularly designed to reduce transverse resonant vibration response of a supported cylinder structure at its dominant two modes. Various testing configurations and techniques have been used such as transmissibility measurements, frequency response measurements, sweep sine testing, impact testing, and random testing. Different testing approaches were needed to e...
Citation Formats
G. H. Ak, “Assessment of performance of interpolation methods for temporal resolution of wind data on wave modelling,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Civil Engineering., Middle East Technical University, 2019.