STUDI EKSPERIMENTAL KARAKTERISASI SPRAY PADA PROSES AIR-LIQUID ATOMIZATION MENGGUNAKAN ORIFICE MIST GENERATOR DAN APLIKASI TERHADAP PENINGKATAN RELATIVE HUMIDITY SERTA PENGURANGAN KADAR CO2 DI UDARA

AQLI HAQ, Dr. Deendarlianto, S.T., M.Eng.

2014 | Skripsi | TEKNIK MESIN

Penelitian tentang proses atomization telah banyak dilakukan. Penelitian menjadi sangat menarik karena memiliki banyak manfaat. Salah satu aplikasi dari proses ini adalah fuel spray untuk proses pembakaran di dalam motor bakar dengan menggunakan injektor sehingga konsumsi bahan bakar lebih hemat. Lalu di bidang kesehatan, proses atomization juga dimanfaatkan untuk aplikasi pengobatan nasal spray. Alat yang digunakan untuk melakukan proses atomization disebut atomizer. Pada penelitian ini atomizer disebut mist generator, karena droplet air yang dihasilkan memilikki diameter antara 30 -70 mikron. Untuk mengukur ukuran droplet air, digunakan teknik image processing. Mist generator yang digunakan merupakan tipe orifice, dengan poros pipe di bagian tengah. Udara dengan kapasitas yang tinggi mengalir melalui orifice, sehingga menyebabkan pressure drop dan menghasilkan tekanan vakum pada bagian tengah dari mist generator. Akibat terjadi tekanan vakum, air di dalam tangki akan terhisap menuju mist generator. Pada penelitian ini akan menggunakan 3 konfigurasi mist generator. Variabel yang diteliti dari ketiga konfigurasi tersebut adalah mist generation efficiency, pneumatic power, dan tekanan pada bagian inlet, suction, dan outlet. Masing-masing konfigurasi akan diamati pengaruhnya terhadap peningkatan relative humidity dan pengurangan kadar karbondioksida (CO2) di udara.

In this study, described the characteristics of the resulting spray of twin-fluid atomization process using orifice mist generator. This process will produce small water droplets are then called mist. The air supplied by the compressor at a pressure of 300 kPa to the mist generator. In the mist generator will occur pressure drop caused by the difference in surface area at the inlet and outlet of orifice. Pressure drop causes the pressure on the center of the mist generator into a vacuum pressure. So that the middle of the mist generator is also called suction section. The vacuum pressure causes the water in the tank to be sucked to the mist generator . In the mist generator will be there is an interaction between air and water, where the water undergoes shear stress caused by the air at high rate velocity.Mist generator that used in this experiment have 3 different configurations. Three configurations of the mist generator will observe about its influence on the increase in relative humidity and reduction of CO2 levels in the air. Performance of each of the mist generator can be seen in several variables that is pneumatic power, mist generation efficiency, and also ther pressure in inlet, suction, and outlet section. The result showed that the mist generator configuration A has the best ability to increase the relative humidity and reduce the levels of CO2 in the air. While the mist generator configuration C has the lowest pneumatic power and mist generator confuguration B has the highest mist generation efficiency. And also higher capacity of air flowrate will further increase pressure in inlet section, increase vacumm pressure in suction section.

Kata Kunci : atomization, mist generation efficiency, pneumatic power, pressure drop, relative humidity, karbondioksida.