Simulasi Sistem Pendingin Berbasis Refrigerated Sea Water (RSW) Untuk Palka Kapal Purse Seine 30 GT

Nurhasan, Nurhasan (2026) Simulasi Sistem Pendingin Berbasis Refrigerated Sea Water (RSW) Untuk Palka Kapal Purse Seine 30 GT. Masters thesis, Institut Teknologi Sepuluh Nopember.

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Abstract

Penggunaan es balok oleh nelayan tradisional di Pelabuhan Muncar, Banyuwangi, memiliki keterbatasan teknis dan ekonomis, seperti penambahan beban kapal yang meningkatkan konsumsi BBM serta berkurangnya kapasitas muat palka. Penelitian tesis ini bertujuan merancang dan menganalisis kinerja sistem pendingin berbasis Refrigerated Sea Water (RSW) dengan metode closed-loop recirculation untuk palka kapal purse seine 30 GT (KM Kota Abadi). Sistem ini dirancang untuk mendinginkan 11.144 kg ikan pelagis dari temperatur 30 °C menjadi −5 °C dalam target waktu 3 jam. Dari hasil kalkulasi analitik, diperoleh total beban pendinginan sebesar 4.094 MJ, sehingga dibutuhkan kapasitas refrigerasi desain sebesar 436 kW menggunakan refrigeran R404A dan kompresor semi-hermetic screw. Sistem sirkulasi air laut dingin ini membutuhkan debit aliran sebesar 100 m³/jam yang didistribusikan secara merata melalui 8 unit spray nozzle per palka dengan kecepatan semprotan 8 m/s. Evaluasi kinerja pendinginan dilakukan melalui simulasi transien 3D Computational Fluid Dynamics (CFD) menggunakan ANSYS Fluent pada variasi tingkat pengisian palka 90% dan 70%. Model numerik divalidasi terhadap hasil analitik transien detik ke-30 dan menunjukkan kesesuaian yang sangat tinggi dengan persentase kesalahan (percentage error) Area-Weighted Average Wall Heat Flux hanya sebesar 3,22% (7.989,13 W/m² pada numerik berbanding 7.740,00 W/m² pada analitik). Hasil simulasi mengungkapkan bahwa meskipun distribusi temperatur udara palka pada kedua variasi relatif serupa (~271 K hingga ~307 K), parameter wall heat flux pada permukaan ikan menunjukkan perbedaan efektivitas pendinginan yang signifikan. Pengisian palka 70% terbukti lebih efektif dan cepat karena beban termal yang lebih rendah, sedangkan pengisian 90% menyebabkan pelepasan kalor berjalan lebih lambat dengan heat flux maksimum tertahan di angka 6.687 W/m² (18,3% lebih tinggi dari variasi 70%).
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The use of block ice by traditional fishermen at Muncar Port, Banyuwangi, presents technical and economic limitations, such as increased vessel weight leading to higher fuel consumption and reduced cargo hold capacity. This thesis research aims to design and analyze the performance of a Refrigerated Sea Water (RSW) cooling system using a closed-loop recirculation method for the hold of a 30 GT purse seine vessel (KM Kota Abadi). The system is designed to cool 11,144 kg of pelagic fish from an initial temperature of 30 °C down to −5 °C within a target time of 3 hours. Based on analytical calculations, the total cooling load required is 4,094 MJ, necessitating a design refrigeration capacity of 436 kW using R404A refrigerant and a semi-hermetic screw compressor. The chilled seawater circulation system requires a flow rate of 100 m³/h, evenly distributed through 8 spray nozzles per hold at a spray velocity of 8 m/s. Cooling performance evaluation was conducted through 3D transient Computational Fluid Dynamics (CFD) simulations using ANSYS Fluent across 90% and 70% hold filling rate variations. The numerical model was validated against the transient analytical results at the 30th second, demonstrating high agreement with a percentage error in Area-Weighted Average Wall Heat Flux of only 3.22% (7,989.13 W/m² for the numerical model versus 7,740.00 W/m² for the analytical method). Simulation results revealed that although the air temperature distribution inside the hold was relatively similar for both variations (~271 K to ~307 K), the wall heat flux parameter on the fish surface showed significant differences in cooling effectiveness. A 70% filling rate proved to be faster and more effective due to lower thermal load and minimal shadowing effect, whereas a 90% filling rate resulted in slower heat dissipation with a maximum heat flux peaking at 6,687 W/m² (18.3% higher than the 70% variation).

Item Type:	Thesis (Masters)
Uncontrolled Keywords:	Refrigerated Sea Water (RSW), Purse seine, fish hold, simulation CFD, ANSYS Refrigerated Sea Water (RSW), Purse seine, fish hold, simulation CFD, ANSYS
Subjects:	Q Science Q Science > QC Physics > QC151 Fluid dynamics
Divisions:	Faculty of Marine Technology (MARTECH) > Ocean Engineering > 38101-(S2) Master Thesis
Depositing User:	Nurhasan Nurhasan
Date Deposited:	05 Aug 2026 04:15
Last Modified:	05 Aug 2026 04:15
URI:	http://repository.its.ac.id/id/eprint/143843

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