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Abstrak :
Sistem pendinginan konvesional pada piranti elektronik dengan menggunakan fan sudah tidak efektif dan memadai untuk diaplikasikan sekarang ini. Miniaturisasi produk dengan performa kinerja yang semakin canggih menyebabkan diperlukannya sistem pendingin baru yang mempunyai efisiensi termal yang tinggi dan juga hemat energi. Jet sintetik dapat dijadikan sistem pendinginan baru berdasar input massa netto nol tetapi momentum tidak nol. Dalam penelitian ini dua buah membran jet sintetik dengan tipe aliran silang (Cross-Flow) diuji dan dianalisa untuk membandingkan karakteristik efek pendinginan yang masing-masing membran digetarkan dengan menggunakan variasi gelombang sinusoidal dan square. Penelitian dilakukan dengan menggunakan metode komputasi dan eksperimental. Pada tahap komputasional penelitian ini menggunakan software CFD Fluent dengan model turbulensi k-w SST dengan elemen meshing Quad tipe Pave. Pada tahapan eksperimen, digunakan 2 function generator untuk menggerakkan membran dengan menggunakan variasi fungsi frekuensi Sinusoidal dan Square untuk 5 prototype uji pada masing-masing percobaan serta tiga frekuensi osilasi yaitu 80 Hz, 120 Hz, dan 160 Hz serta heat flux konstan 10 W/m2,25 W/m2, dan 50 W/m2 pada amplitudo tetap 0.002 m/s. Penelitian menggunakan jet sintetik ber-tipe aliran silang bertujuan untuk memperbaiki serta mengoptimumkan proses pendinginan jet sintetik akibat adanya confinement effect atau efek sekam dimana panas yang dibuang akan terakumulasi kembali pada cavity dari jet sintetik sehingga pendinginan pada heatsink terhenti. Pada riset kali ini akan dilihat seberapa lama waktu optimum pendinginan jet sintetik ber-tipe aliran silang serta frekuensi osilasi ter-optimum dalam proses pendinginan heat sink. ...... Current advancement of micro electronic devices have made the conventional fan-based cooling is no longer effective and applicable. Miniaturization with higher performance of electronic products causes the need for a new cooling system that has high thermal efficiency and low energy consumption. Synthetic jet which is based on zero netto mass input but non zero momentum is a new approach utilized for cooling system. The synthetic air jet was generated by vibrating membranes which pushed out the air from the cavity through the exit nozzles with oscillatory motion. The main purpose of this synthetic jet was to create vortices pair to come out from nozzle which will accelerate the heat transfer process occurring at the heat sink. This research investigated the forced cooling characterization of a cross flow synthetic jet using double membrane actuator with two different variations of sinusoidal and square wave and was conducted both in computational as well as also experimental stage. Computational stage was conducted by a commercial CFD software of Fluent® with a turbulence model k- ω SST with meshing elements quad type pave, while in the experimental work the function generators was used to drive the membranes with the variation of sinusoidal and square wave in three oscillation frequencies i.e 80 Hz, 120 Hz, and 160 Hz at fixed amplitude of 0.002 m/s for condition of constant heat flux for 10 W/m2,25 W/m2, dan 50 W/m2. The main purpose of this research is to improve and optimizing the process of synthetic jet cooling by suppressing the confinement effect. The confinement effect phenomena, which commonly occurs an impinging synthetic jet flow, causes the hot air is sucked back and will accumulate into the cavity of synthetic jet actuator and will reduce the cooling effect. The experimental results show significant effect of the reduction of the confinement effect phenomena by using the cross flow synthetic jet. The best heat transfer rate hence the optimum cooling effect was obtained at a lower oscillation frequency; in this study at sinusoidal 120 Hz - square 80 Hz.