Turbulent Mixing in Raja Ampat Sea

Abstract:

Raja Ampat Sea has a complex geometry and passed by Indonesian Throughflow (ITF) causing a very dynamic water condition, that condition also amplified by turbulent mixing. To gain better understanding of process and extent of turbulent mixing in Raja Ampat Sea, this research calculate Brunt-Vaisala frequency, Richardson number, turbulent kinetic energy dissipation rate and vertical diffusivity coefficient. The data obtained from Expedition Widya Nusantara (EWIN) by P2O-LIPI in the territorial of Raja Ampat Sea on 14-24 November 2007, by using 12 out of 33 observation stations. From this research, it is known that in 0-40 m (mixed layer) and 250-400 m (deep layer) have Richardson number (R_i) less than 0.25 and high vertical diffusivity coefficient (K_v), It proves a strong turbulent mixing occurs at those depth. Furthermore, Raja Ampat Sea has strong turbulent mixing with average value of turbulent kinetic energy is 2.64 WKg^-1and vertical diffusivity coefficient is 1.65x10^-3 m²s.

• Periodical: Applied Mechanics and Materials (Volume 862)
• Pages: 9-15
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.862.9
• Online since: January 2017
• Authors: Aditya Pamungkas*, Ivonne M. Radjawane, Hadikusumah Hadikusumah
• Keywords: Indonesian Throughflow (ITF), Raja Ampat Sea, Turbulent Kinetic Energy Dissipation, Turbulent Mixing, Vertical Diffusivity

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