KAJIAN PENGHEMATAN ENERGI LISTRIK UNTUK MEREDUKSI KONSUMSI BAHAN BAKAR SPESIFIK(SFC) GENERATOR SET CADANGAN PADA GEDUNG POLITEKNIK MUARA TEWEH

Sistem kelistrikan di wilayah Muara Teweh merupakan sistem kelistrikan yang tidak terinterkoneksi dengan sistem kelistrikan Kalimantan Selatan dan Tengah, dimana sampai tahun 2015 kapasitas terpasang diproyeksikan belum dapat memenuhi kebutuhan beban puncak sehingga mengalami defisit 1 MW yang mengakibatkan sering terjadi pemadaman bergilir. Hal ini berimbas kepada pelanggan sehingga untuk mengatasinya Politeknik Muara Teweh mengoperasikan generator set berkapasitas 140 kVA sebagai pembangkit listrik cadangan dengan bahan bakar jenis solar. Berdasarkan hasil penelitian ini, kebutuhan daya listrik pada saat beban puncak di gedung Politeknik Muara Teweh sebesar 94,168 kW dengan konsumsi bahan bakar spesifik sebanyak 28,16 liter dalam 1 (satu) jam pengoperasiannya. Dengan manajemen energi yang baik, gedung Politeknik Muara Teweh dapat melakukan penghematan samapai 50% dari beban puncak dengan penghematan konsumsi bahan bakar spesifik dalam pengoperasiannya sebesar 14,08 liter setiap jam.Keywords— Generator set, kapasitas terpasang, beban puncak, konsumsi bahan bakar spesifik/Break Specific Fuel Consumption (BSFC) dan Break Horse Power (BHP).

Pengaruh Rasio Campuran Napthalene pada Premium terhadap Efisiensi Bahan Bakar dan Kinerja Mesin Sepeda Motor 4tak

ABSTRAKPemerintah Indonesia berharap kualitas baik dari gas buang kendaraan khususnya sepeda motor, diperlukan bahan bakar kualitas tinggi yaitu bahan bakar dengan nilai oktan tinggi. Napthalene adalah senyawa hidrokarbon dengan rumus kimia C10H16O. Struktur kimia yang mirip bensin, memiliki rantai lebih panjang membuat Napthalene diduga dapat meningkatkan nilai oktan bensin. Tujuan penelitian yaitu menganalisis pengaruh rasio pencampuran Napthalene pada premium terhadap konsumsi bahan bakar (km/l) dan peningkatan kinerja pada mesin sepeda motor bebek jenis manual 110 cc dan 115 cc. Metodenya adalah eksperimen. Parameternya yaitu tingkat efisiensi konsumsi premium (km/l), peningkatan kinerja meliputi torsi dan daya (Horse Power) pada motor jenis tersebut.Rasio perbandingan Napthalene dan premium yaitu 3 gram/l, 6 gram/l dan 9 gram/l. Hasil uji menunjukkan rasio pencampuran Napthalene pada premium sebanyak 9 gram/l merupakan yang paling berpengaruh terhadap tingkat efisiensi konsumsi premium dan kinerja mesin pada kedua jenis motor tersebut. Aplikasi tersebut tentunya akan memperbaiki kualitas gas buang.Kata kunci : efisiensi, premium, naphthalene, nilai oktan ABSTRACTThe Indonesian government hopes that the good quality of vehicle exhaust gases, especially motorcycles, requires high quality fuel, namely fuel with a high octane rating. Napthalene is a hydrocarbon compound with the chemical formula C10H16O. The chemical structure is similar to gasoline, having a longer chain makes Napthalene allegedly able to increase the octane value of gasoline. The purpose of the study was to analyze the effect of the Napthalene mixing ratio at premium on fuel consumption (km/l) and performance improvement on the 110 cc and 115 cc manual motorcycle engines. The method is experimental. The parameters are the level of premium consumption efficiency (km/l), increased performance including torque and power (Horse Power) on this type of motorcycles. The ratio of Napthalene and premium is 3 grams/l, 6 grams/l and 9 grams/l. The test results show that the Napthalene mixing ratio at premium as much as 9 grams/l is the most influential on the level of premium consumption efficiency and engine performance on both types of motorcycles. The application will certainly improve the quality of exhaust gas.Keywords: efficiency, premium, naphthalene, octane rating

ANALISA PERHITUNGAN DAYA MESIN KAPAL MENGGUNAKAN METODE GULDHAMER-HARVALD

<p>Dalam sistem penggerak kapal dengan Metode Guldhammer – Harvald adalah suatu metode untuk menentukan besarnya daya mesin yang sesuai dengan propeller pada kapal. Tahapan metode Harvald dimulai dari menentukan : Effective Horse Power (EHP), Delivered Horse Power (DHP), Shaft Horse Power (SHP), Brake Horse Power (BHP). Dari hasil pencarian tersebut didapat daya sebesar 5.820,071 HP, sehingga daya mesin tersebut sesuai yang beredar di parasan merk CAT 280-16. Dengan menentukan daya yang sesuai kebutuhan kapal, maka kapal dapat bergerak dengan kecepatan yang di inginkan.</p><p> </p><p><strong>Kata kunci :</strong> Daya Mesin, Metode Guldhammer – Harvald</p>

Effect of Refrigeration Assisted Intercooler Turbocharging on Engine’s Horse Power

The stringent regulations on fuel saving and emissions reduction in the transportation sector have become game-raisers in the development of present internal combustion engines for road applications, even if under-the-hood space constraints, downsizing and down-weighting prevent from adopting radical changes in the engine layout. In current research, objective is to find a viable and pragmatic solution to reduce the turbo-charged engine intake air temperature by a large value as compared to traditional air-to-air intercoolers to increase Engine Horsepower. In undergoing research, a refrigerated intercooler is designed on the basis of refrigeration cycle, which further decreases the intake air temperature of the engine, resulting in increased horsepower, and improved Formula 1 lap times. Additionally, Formula 1, 2014 (V6 Turbo-Charged) Engine is used. According to the results, horse power of 1209.74HP is obtained by using refrigeration assisted intercooler. However, 1061HP is obtained for air to air intercooler. So, performance gain of 15 to 20% over present intake air cooling system in Formula 1 engine cars is successfully achieved. Additionally, Research will be utilized to decrease lap time in formula 1 racing cars.

Performance Evaluation of Single Row-Low Horse Power Tractor Operated Vegetable Transplanter

Mini tractor (18 hp) operated single row vegetable transplanter was developed for Tomato and Brinjal crop transplanting. A simple rotating magazine type metering system was attached to the transplanter. The performance evaluation was done in was 20× 10 m at 1.0, 1.5 and 2.5 km/h. But at low speed i.e 1.0 km/h the results were in acceptable range. The main parameters of the developed transplanter were planting angle and missing percentage. Planting angle was 3.02 and 2.45º, similarly missing percentage was 9.5 and 8.78 % for Tomato and Brinjal respectively. The field-capacity and transplanting-efficiency were obtained 0.05 ha h-1 and 83.3% respectively. Breakeven area obtained as 0.42 ha and payback period was 44.71 h.

Kaji Eksperimental Perbandingan Performa Engine4 Langkah MenggunakanBahan Bakar Hasil Pirolisis Sampah Plastik dan Premium

Penelitian yang dilakukan dalam tulisan ini terkait pengujian performa engine 4 langkah menggunakan bahan bakar hasil pirolisis sampah plastik (BBHPSP) dan dibandingkan dengan bahan bakar standar, yaitu premium. Pengujian dilakukan dengan menggunakan parameter tetap berupa volume bahan bakar (20 cc) dan kecepatan engine pada 4500 rpm yang dijaga konstan. Untuk memetakan performa engine 4 langkah menggunakan kedua jenis bahan bakar divariasikan besar pembebanan di poros keluaran engine. Berdasarkan pengukuran yang dilakukan diperoleh temperatur ruang bakar dan temperatur gas buang di exhaust manifoldmenggunakantermokopel. Hasil ini digunakan untuk menghitung performa engine 4 langkah yang menunjukkan bahwa performa engine 4 langkah dengan BBHPSP masih berada di bawah performa engine dengan premium. Pada penelitian ini diketahui bahwa kerja keluaran, indicated horse power (IHP), dan efisiensi termal engine dengan BBHPSP lebih rendah masing-masingnya dalam rentang 8,0 – 11,7%; 20,8 – 32,1%; dan 9,6 – 17,7% terhadap nilai premium. Akan tetapi, konsumsi bahan bakar spesifiknya lebih tinggi dibandingkan dengan premium yaitu sebesar32,4 – 53,1%. Selanjutnya, hubungan antara konsumsi bahan bakar spesifik dengan kerja keluaran, IHP, dan efisiensi termal memenuhi fungsi kudratik.Secara umum dapat disimpulkan bahwa BBHPSP dapat digunakan sebagai bahan bakar alternatif dengan perlunya proses perlakuan setelah pirolisis selesai dilakukan atau penambahan katalis dalam proses. This research was conducted to determine performance measurement of a four-stroke engine using fuel from pyrolisis procsess of plastic waste (BBHPSP) and gasoline as a standard fuel. The measurements were performed by keeping the fuel volume and engine rotation at constant value at 20 cc and 4500 rpm, respectively. To map the performance of four-stroke engine, it can be achieved by varying the magnitude of load at the output shaft. Temperature was also measured using thermocouple at combustion chamber and exhaust manifold. These measurements were applied to determine the performance of four-stroke engine. It gave the value of four-stroke engine using BBHPSP was lower than the use of gasoline. These values were 8,0 – 11,7%foroutput work, 20,8 – 32,1% for indicated horse power (IHP), and 9,6 – 17,7% for thermal efficiency comparing to the use of gasoline. Meanwhile, the specific fuel consumption of BBHPSP was greater than gasoline about 32,4 – 53,1%. Afterwards, the relation of specific fuel conumption with output works, IHP and thermal efficiency fulfilled the quadratic functions. To conclude, BBHPSP can be used as an alternative fuel for the four-stroke engine by considering a post-treatment or adding a catalyst when producing BBHPSP using pyrolisis proccess.

Market Research on Factors Influencing the Buying Decision on Tractors by Farmers in Adilabad District, Telangana

Consumer makes buying decision in everything they buy in their lives. It deals from purchasing to evaluating it after purchase so, market research on factors influencing the buying decision is necessary. Hence, the study focus on buying decision on tractors by farmers and penetration level of tractors in each market segment in Adilabad district, Telangana state from January –march 2020. Garrett ranking technique and arithmetic mean were used to analyse the data. The study revealed that 5 different tractor brands of tractors, viz. Eicher, Mahindra, Swaraj, John Deere and Escorts with different models. Farmers ranked Fuel/Oil efficiency as the first factor in purchase of tractor Farmers ranked fuel/oil efficiency as the first factor in purchase of tractor followed by subsidies, maintenance cost, horse power, low priced tractor, recommendations by relatives/friends/local mechanics/dealers/company persons, brand reputation, spare parts, product appearance, service of the company, sales promotion/ gift scheme, easy availability of finance and resale value in the descending order of ranking. Dealer ranked the factors that the farmers considered in tractor purchase were subsidy followed by fuel efficiency, maintenance cost, low price, horse power, recommendation by relatives/ local mechanics/ dealers/ company persons, spare parts, recommendation of people on brand, product appearance, service of company, sales promotion/gift scheme, and resale value in the descending order of ranking. Apart from these, the sample farmers believed that 40-50 horse power segment was the most suitable segment for the selected area and it is ranked first by sample farmers. Greater than 50 horse power segment was the next suitable segment 3 per cent 30-40 horse power segment was preferred by 2 per cent of the sample farmers.

ANALISIS HAMBATAN GESEK KAPAL MODIFIKASI DARI KAPAL JARING INSANG MENJADI KAPAL PANCING TONDA DI PALABUHANRATU (Evaluation of Ship Resistance from the Modification of Gillnets Vessel Into Troll Lines Vessel in Palabuhanratu)

Transformasi alat tangkap jaring insang ke pancing tonda adalah upaya untuk meningkatkan hasil tangkapan. Pergeseran alat tangkap ikan telah menyebabkan perubahan dalam metode penangkapan ikan, dan mempengaruhi pergerakan kapal. Saat ini nelayan memodifikasi bagian badan kapal, pemasangan mesin yang belum memasukkan standar perhitungan dalam pembangunannya. Penelitian ini bertujuan adalah untuk mengidentifikasi kemampuan mesin kapal saat beroperasi, dilihat dari hambatan gesek dan tenaga mesin kapal. Metode pengumpulan data yang digunakan dalam penelitian ini adalah accidental sampling. Data diambil menggunakan metode observasi langsung, pengukuran dimensi utama kapal, wawancara ke Nahkoda “KM Untukmu" dan studi pustaka. Data-data tersebut dianalisa dengan menggunakan metode Holtrop untuk mencari nilai hambatan gesekan kapal, metode Telfer untuk mengubah nilai resistensi menjadi nilai gaya propulsi dan metode Nomura dan Yamazaki untuk mencari nilai Brake Horse Power (BHP). Dimensi utama kapal yang diukur adalah tinggi (D), lebar (B), panjang garis air (lwl) dan draft (d). Hasil studi menyimpulkan bahwa, mesin utama “KM Untukmu” memenuhi persyaratan kecepatan yang dibutuhkan untuk melakukan operasi penangkapan ikan, yaitu 4-8 knot dan tinggi draft 1 meter dengan nilai hambatan gesek 257,96-920,64 Newton (N m/s) dan dengan nilai HP yang dibutuhkan berkisar 2,155-23,48 HP. Mesin utama “KM Untukmu" telah memenuhi kebutuhan yang diperlukan untuk melakukan operasi pancing tonda dan mampu bergerak hingga kecepatan 11,12-12,92 knot. Transforming gill nets into troll line rods is an attempt to increase the number of catches. The shift of fishing gear has caused changes in fishing methods, this has affected the ship movements. Now fishermen are modifying ship’s body parts, machinery installation, and its main engine even though they didn’t include shipping calculation standard in its construction. This study objectives are identifying ship's engine performance during fishing operation, which seen from friction resistance and ship’s engine thrust. Data collection method used is direct sampling. Data taken using direct observation method, i.e. of the ship’s main dimensions measurements, Chief of “KM Untukmu” interviews and literature studies. Data analyzed using Holtrop method in order to find ship friction resistance value, and Nomura and Yamazaki method to calculate Brake Horse Power (BHP) value. Ship main dimensions measured are depth (D), breadth (B), length of water line (lwl) and draft (d). Study shows that KM Untukmu’s main engine meets speed requirements needed to carry out fishing operations, namely 4-8 knots and one meters draft height with friction resistance value of 257.96 – 920.64 Newton (N m/s) with HP value needed around 2.15 – 23.48 HP. “KM Untukmu” main engine has fulfilled troll line operation requirements and is capable in moving up the speeds up to 11.12 – 12.92 knots.