MODIFIKASI COOLING TOWER TIPE INDUCED DRAFT ALIRAN COUNTERFLOW ( MODIFICATION INDUCED DRAFT COOLING TOWER TYPE FLOW COUNTERFLOW )

Abstract

Proses Modifikasi Cooling Tower Tipe Induced Draft Aliran Counterflow bertujuan untuk meningkatkan performa cooling tower yang sebelumnya masih terdapat kekurangan. Modifikasi cooling tower ini dilakukan dengan menambahkan potongan - potongan pipa PVC setinggi 10 cm sebagai bahan pengisi, mengganti exhaust fan yang lama dengan exhaust fan yang baru, serta menambahkan komponen indikator seperti termometer dan RH meter. Pada proses modifikasi cooling tower ini dilakukan dengan beberapa pendekatan diantaranya termodinamika, perpindahan kalor dan mekanika fluida. Pengujian tugas akhir ini dilakukan dengan menggunakan alat ukur thermometer, thermohygrometer, anemometer, dan flowmeter pada cooling tower. Hasil pengujian dengan menggunakan kapasitas 2 l/min sampai 22 l/min menunjukkan bahwa efektivitas cooling tower berkisar 11,76 % s.d 29,74 % dengan rata - rata 20,84 %; cooling range 3,2ºC sampai 6,9ºC dengan rata-rata 5,11ºC; approach berkisar 16,3ºC sampai 25,2ºC dengan rata-rata 19,87ºC. Kapasitas pendinginan berkisar 0,67 kW s.d. 7,56 kW dengan rata - rata 4,17 kW. Perbandingan L/G 0,1758 s.d 0,7143 dengan rata - rata L/G 0,3168 (kg air/ kg udara). Number of transfer unit (NTU) berkisar 0,1368 s.d. 1,5713 dengan rata - rata NTU 0,6950 kW/(kj/kg beda entalpi). Kata kunci : cooling tower, modifikasi, cooling range, approach, efektivitas, kapasitas pendinginan Modification Process Induced Draft Cooling Tower with Counterflow is made to improve cooling tower performance that previously there are still shortcomings. Cooling tower modification is done by adding the height of 10 cm PVC pipe as a filler material, replacing the old exhaust fan exhaust fan with a new one, and adding components such as temperature indicators temperature and RH meter. In the process of cooling tower modification is done by several approaches including thermodynamics, heat transfer and fluid mechanics. The study was conducted by using a thermometer measuring devices, thermohygrometer, anemometer, and a flowmeter on the cooling tower. The test results by using the capacity of 2 l/min to 22 l/min showed that the effectiveness of cooling tower range 11.76% to 29.74% with an average of 20.84%; cooling range of 3.2 ºC to 6.9 ºC with an average of 5.11 ºC; approach ranges from 16.3 ºC to 25.2 ºC with an average of 19.87 ºC. Capacity of cooling range 0,67 kW to 7,56 kW with an average 4,17 kW. Comparison of L/G 0,1758 to 0,7143 with an average L/G 0,3168 (kg water / kg air). Comparison of NTU about 0,1368 to 1,5713 with an average NTU 0,6950 kW/(kJ/kg different enthalpy). Keywords : cooling tower, modification, cooling range, approach, effectiveness, cooling capacity