Karakteristik temperatur fluida dingin pada grooved double pipe heat exchanger

Heat exchangers have widespread applications in many industrials process. There are many kind of heat exchanger. One of the simply heat exchanger is double pipe heat exchanger. The need for lightweight and enhancing the heat transfer of heat exchanger accomodated by surface engineering. One of the surface passive technique applications is groove. Incising groove in pipe as concerned wide consideration as it need no additional power, decrease in weight of system and hence give more benefit in heat transfer. The characteristics of heat transfer in grooved double pipe heat exchanger was investigated experimentally in this article. The aim of this investigation is to reveal the phenomenon of temperature characteristics of cold fluid in the heat transfer process in the grooved double pipe heat exchanger. In this study, water are used as both hot and cold fluid with counter flow pattern, and the water flow rate equal to 15 lpm for both fluid. Grooves were incised on the annulus area in the outer wall of tube side with rectangular shape and circumferential pattern. The characteristics of groove dimension that are height of groove is 0,3 mm; distance between grooves is 8 mm; and the groove space which is as independent variables are 1 mm and 2 mm. The data from 1 mm and 2 mm grooves space were compared with no grooved double pipe heat exchanger data (smooth pipe). The hot fluid temperature is 50 ± 0,50C while the cold fluid temperature is 30 ± 0,50C. The temperature data on the inlet and outlet side of heat exchangers for smooth pipe, 1 mm and 2 mm groove space were compared to find out the characteristics of increasing cold fluid temperature. This study used the temperature rate and temperature acceleration method to compare the variables. The result shows that groove installation increases the amount of heat absorbed by cold fluid. The heat exchanger with 1 mm groove spaces, was able to absorb heat about ± 2.3 % better than heat exchanger with 2 mm groove space and 13,1 % better than heat exchanger with no groove

The Effectiveness of Using Continuous Variable Transmission (CVT) in 2WD Buggy Vehicles

Continuous Variable Transmission (CVT) is a transmission system that does not have gears like in manual transmission cars or conventional automatic transmission cars. CVT has the advantage of being able to maintain the proper rotational speed at any time in terms of engine efficiency by changing the speed ratio flexibly and continuously. A continuously variable transmission (CVT) is a transmission that can change steplessly through an infinite effective gear ratio between maximum and minimum. This is in contrast to other mechanical transmissions which only allow a few different gear ratios to choose. The flexibility of the CVT allows the drive shaft to maintain a constant angular speed over the output speed range. Torque is transmitted from the drive to the pulley which is driven by friction acting between the belt and pulley surfaces. Tests were carried out using a dynotest to obtain wheel rotation data and the resulting torque. The loading is given from 3 kg, 5 kg, 7 kg and 8 kg, the engine rpm used is 5500 rpm, 6000 rpm, 6500 rpm, 7000 rpm and 8000 rpm. Rear wheel rotation is inversely proportional to the load, the greater the load the rotation will decrease. Load is directly proportional to torque, the greater the load given the torque will increase. The CVT system is still effective for use as a power successor. The power that can be transmitted is still greater than 50%, namely 68%.Continuous Variable Transmission (CVT) is a transmission system that does not have gears like in manual transmission cars or conventional automatic transmission cars. CVT has the advantage of being able to maintain the proper rotational speed at any time in terms of engine efficiency by changing the speed ratio flexibly and continuously. A continuously variable transmission (CVT) is a transmission that can change steplessly through an infinite effective gear ratio between maximum and minimum. This is in contrast to other mechanical transmissions which only allow a few different gear ratios to choose. The flexibility of the CVT allows the drive shaft to maintain a constant angular speed over the output speed range. Torque is transmitted from the drive to the pulley which is driven by friction acting between the belt and pulley surfaces. Tests were carried out using a dynotest to obtain wheel rotation data and the resulting torque. The loading is given from 3 kg, 5 kg, 7 kg and 8 kg, the engine rpm used is 5500 rpm, 6000 rpm, 6500 rpm, 7000 rpm and 8000 rpm. Rear wheel rotation is inversely proportional to the load, the greater the load the rotation will decrease. Load is directly proportional to torque, the greater the load given the torque will increase. The CVT system is still effective for use as a power successor. The power that can be transmitted is still greater than 50%, namely 68%

Cutting Speed Analysis of Organic Waste Chopping Machine Fly Wheel Model Level Control

This machine is used to chop leaves, twigs and branches into very small pieces, to avoid the bad smell due to the decay of organic waste and can be used as compost. The amount of cutting speed on the organic waste chopping machine with a chopping time of 2.5 kg of ketapang leaves is the average time obtained without fly wheels 2.0 minutes and with fly wheels 1.7 minutes, a time difference of 0.3 minutes. The chopping time of 2.5 kg of ketapang branches with an average time obtained without a fly wheel of 2.2 minutes and with a fly wheel of 2.0 minutes, a time difference of 0.2 minutes. The chopping time of teak branches is 2.5 kg with an average time obtained without a fly wheel of 2.6 minutes and with a fly wheel of 2.0 minutes, so the time difference is 0.6 minutes. So the cutting speed using a fly wheel is better. The results of the productivity obtained on the organic waste chopping machine, for the results of leaf chopping productivity without a fly wheel of 48% and those using a fly wheel of 58%, and the results of leaf chopping with a fly wheel are 10% more productive, for the productivity of chopping twigs without a fly wheel of 44% and those using a fly wheel of 49%, so the results of chopping twigs with a fly wheel are 5% more productive, and the results of chopping branches without a fly wheel of 37% and those using a fly wheel of 49%, so the results of chopping branches with a fly wheel are 12% more productive

PEMANFAATAN TEKNOLOGI TEPAT GUNA BERUPA MESIN PENCACAH PAKAN TERNAK KAMBING DI DESA SEPANG KABUPATEN BULELENG

Kegiatan Pengabdian kepada Masyarakat melalui program Ipteks Bagi Masyarakat bertujuan mengatasi berbagai permasalahan yang dihadapi oleh mitra kelompok peternak kambing Sumber Rejeki dan Tunas Mekar, sehingga dapat meningkatkan produktivitas pakan ternak kambing dan produksi susu kambing. Permasalahan yang dihadapi oleh mitra adalah belum memiliki mesin pencacah pakan ternak, sehingga pada saat musim kemarau sangat sulit mendapatkan pakan ternak, Penerapan teknologi tepat guna pada proses pengolahan pakan ternak berupa ranting lantoro, gamal, dan berupa daun. Sebelum program dilaksanakan peternak kambing dapat memotong pakan ternak sebanyak 40-50 kg/hari. Setelah program dilaksanakan dengan penerapan mesin pemotong ranting untuk pakan ternak ada peningkatan hasil pakan ternak sebesar 60-90 kg/hari dengan hasil cacahan 1-3cm, untuk menjaga kebutuhan pakan ternak dimusim kemarau dilakukan Fermentasi pakan dengan menggunakan drum plastik kapasitas 25 kg. Hasil pelaksanaan program IbM pada Kelompok mitra yaitu 1.Memiliki mesin pencacah pakan ternak. 2. Mempunyai sarana pengoloahan pakan ternak dengan sistem Fermentasi. Dengan adanya sarana tersebut, anggota mitra merasa terbantu dalam mengatasi pengolahan pakan ternak yang mereka hadapi oleh kelompok Ternak Sumber Rejeki dan Ternak Tunas Mekar,”menjadi lebih bersemangat dalam mengembangkan usahany