Wave power

About: Wave power is a research topic. Over the lifetime, 2671 publications have been published within this topic receiving 41439 citations. The topic is also known as: wind wave energy & sea wave energy.

Numerical Forecasting Experiment of the Wave Energy Resource in the China Sea

Abstract: The short-term forecasting of wave energy is important to provide guidance for the electric power operation and power transmission system and to enhance the efficiency of energy capture and conversion. This study produced a numerical forecasting experiment of the China Sea wave energy using WAVEWATCH-III (WW3, the latest version 4.18) wave model driven by T213 (WW3-T213) and T639 (WW3-T639) wind data separately. Then the WW3-T213 and WW3-T639 were verified and compared to build a short-term wave energy forecasting structure suited for the China Sea. Considering the value of wave power density (WPD), “wave energy rose,” daily and weekly total storage and effective storage of wave energy, this study also designed a series of short-term wave energy forecasting productions. Results show that both the WW3-T213 and WW3-T639 exhibit a good skill on the numerical forecasting of the China Sea WPD, while the result of WW3-T639 is much better. Judging from WPD and daily and weekly total storage and effective storage of wave energy, great wave energy caused by cold airs was found. As there are relatively frequent cold airs in winter, early spring, and later autumn in the China Sea and the surrounding waters, abundant wave energy ensues.

Heating experiments in the ion cyclotron range of frequencies on EBT-S

Abstract: Heating experiments in EBT-S have been conducted in steady-state plasmas at continuous wave power levels up to 20 kW in the ion cyclotron range of frequencies (15–30 MHz). Power coupling efficiencies and wave propagation measurements have been obtained at reduced power levels over the frequency range 15–50 MHz. Wave dispersion properties are in qualitative agreement with simplified theory. Substantial ion heating is obtained in deuterium plasmas above 25 MHz, the point at which wave propagation begins. At this frequency, only the 3rd-10th ion cyclotron harmonics of deuterium are present in the core plasma. Ion heating under these circumstances is considerably greater than theoretically predicted for EBT-S parameters. A residual proton component is also heated. However, collisional energy transfer from the protons to the deuterons is too small to account for the deuteron heating. The stored energy of the relativistic electron annuli increases substantially with the application of wave power. Near the antenna, the stored energy more than doubles at a power level of 15 kW. The mechanism producing this dramatic effect is not well understood at present. A small reduction in the ambipolar electric field is also observed during wave heating.

Wave power studies of cusp crossings with the Polar satellite

Abstract: Burst data from the electric field instrument (EFI) on the Polar satellite are used to classify cusp wave properties and the association of the observed waves with particle populations. The most intense wave type (most commonly triggering burst mode data collection) are the broadbanded waves which are then studied in detail using the three-dimensional resolution of the EFI. Finite wavelength effects are removed using two techniques: time-shifting of the sphere potentials to a spacecraft body reference time and spin angle selection. The corrected electric field signal exhibits a uniform spectrum in two dimensions. The wave properties are consistent with two-dimensional turbulence, with phase velocities smaller than the spacecraft velocity and frequency as low as (or lower than) the oxygen gyrofrequency. Owing to their low frequency, we conclude that these waves cannot resonate with and thus heat the ions. The broad k-spectrum and very low frequency in the plasma frame points toward drift or shear instabilities for wave excitation.