Studi Experimental Proses Thermodinamika Udara Pada Pendinginan Indirect Evaporative Cooling Berbasis In-Line Solid Dry Pad. - Arie Prastyo, A A Made; Wijaksana, Hendra; Suarnadwipa, N. (Teknik Desain Mekanika, 2020)
Abstrak Kebutuhan akan sistim pendingin yang lebih hemat energy dan ramah lingkungan, sesuai dengan program green and clean energy yang dicanangkan banyak negara, telah mendorong dilakukannya pengembangan terhadap sistim pendingin evaporative. Sistim indirect evaporative cooling adalah salah satu sistim pendingin evaporative yang mendinginkan udara melalui proses evaporasi dan tanpa adanya kontak langsung udara dan air. Dalam penelitian ini akan dikaji proses thermodinamika udara yang terjadi pada sistim indirect evaporative cooling berbasis solid dry pad. Dalam penelitian ini, dilakukan pengujian proses thermodinamika udara yang terjadi pada variasi prosentase volume pengisian solid dry pad 50% (320 cm3), 75% (480 cm3) dan 100% (640 cm3). Kecepatan aliran udara diatur konstan pada 11.3 m/s. Pencatatan data yang dilakukan termasuk didalamnya temperature bola basah (TwB) dan bola kering (TdB) udara masuk dan keluar solid dry pad. Selanjutnya dilakukan penentuan penurunan temperature bola kering dan penurunan kelembaban relative udara keluar solid dry pad serta penentuan proses thermodinamika yang terjadi pada udara yang melewati solid dry pad menggunakan psychrometric chart.. Sebagai hasil penelitian didapat bahwa penurunan temperature bola kering rata-rata (pendinginan) yang tertinggi dicapai pada prosentase volume pengisian solid dry pad 100% (640 cm3) yakni sebesar 2.35oC dan terendah terjadi pada volume pengisian 50% (320 cm3) yakni sebesar 1.45oC. Sedangkan Penurunan kelembaban relative rata-rata (dehumidifikasi) yang tertinggi dicapai pada prosentase volume pengisian solid dry pad 100% (640 cm3) sebesar 11.0%, dan yang terendah terjadi pada volume pengisian 50% (320 cm3) yakni sebesar 8.1%. Dengan demikian dapat disimpulkan bahwa proses thermodinamika yang terjadi akibat variasi ketiga prosentase volume pengisian solid dry pad adalah pendinginan dan dehumidifikasi dan prosentase volume pengisian solid dry pad sangat berpengaruh terhadap tingkat pendinginan dan dehumidifikasi yang terjadi pada udara yang melewati solid dry pad. Kata kunci : Proses thermodinamika udara, indirect evaporative cooling, in-line solid dry pad, pendinginan dan dehumidifikasi. Abstract Electrical energy needs and environmental impacts caused by the increasingly widespread use of compressor-based air conditioning (AC) systems, has led to the development of an evaporative cooling system that is more energy efficient and environmentally friendly, with sufficient cooling efficiency. The indirect evaporative cooling system is one of the evaporative cooling systems which cools the air through the evaporation process and without direct contact with air and water. This research will study the air thermodynamic process that occurs in the indirect evaporative cooling system based on in-line solid dry pad. In this study, an air thermodynamic process was tested which occurred in the variation of the volume of the filling of solid dry pad 50% (320 cm3), 75% (480 cm3) and 100% (640 cm3). The air flow velocity that passes through the solid dry pad is set at a constant speed of 11.3 m / s. Data recording included wet ball temperature (TwB) and dry ball (TdB) air in and out of the solid dry pad. Next, determine the decrease in dry ball temperature and decrease the relative humidity of the air coming out of the solid dry pad. By plotting wet and dry ball temperature data on a psychrometric chart, the thermodynamic process that occurs in the air passing through the solid dry pad will be determined. As a result of the study it was found that the highest decrease in dry ball temperature (cooling) was achieved at the percentage of solid dry pad 100% (640 cm3) filling volume which was 2.35oC and the lowest occurred at 50% (320 cm3) fill volume which was 1.45 oC. While the highest average relative humidity reduction (dehumidification) was achieved at the percentage of solid dry pad 50% (320 cm3) filling volume by 8.1%, and the lowest occurred at 100% (640 cm3) filling volume of 3.4%. Thus it can be concluded that the thermodynamic process that occurs due to variations in the three percentages of solid dry pad filling volume is cooling and dehumidification and the percentage of solid dry pad filling volumes is very influential on the cooling rate and dehumidification that occurs in the air that passes through the solid dry pad. Keywords: Air thermodynamic processes, indirect evaporative cooling, in-line solid dry pad, prepared and dehumidified