scholarly journals PERUBAHAN KECEPATAN ALIRAN AKIBAT VARIASI VOLUME VEGETASI DI BELOKAN SALURAN IRIGASI

2019 ◽  
Vol 2 (2) ◽  
pp. 114-122
Author(s):  
Muhammad Nasir ◽  
Eldina Fatimah ◽  
Masimin Masimin
Keyword(s):  
Energy Loss ◽  
Flow Rate ◽  
Water Depth ◽  
Local Community ◽  
Secondary Channel ◽  
Flow Area ◽  
Turn Angle ◽  
Irrigation Network ◽  
Speed Distribution ◽  
North Sumatra

D. I Timbang Deli is 520 Ha of flow area and 5000 meters of secondary channel is located in Deli Serdang Regency, North Sumatra Province. The turn of the irrigation network in overgrown vegetation on the cliffs and bottom of the channel, is expected to reduce the flow rate. The purpose of the study was to see the distribution of velocity, resistance and energy loss in the secondary channel due to vegetation. The method used is conducting surveys in the field by measuring water depth, vegetation volume and flow velocity. Trapezoidal channel with 36 m length, 1.45 lower width, 3.15 m upper width and 33,510 turn angle. The velocity measured in the middle and downstream regions across the channel is divided from points X1 to X5 with Q1 = 0.62m3/ sec and Q2 = 0.83 m3/sec. The results obtained in the speed distribution in Q1 Vmax mean X1 = 0.296 m/s and X5 = 0.199 m/s, the speed decreases due to the turn of 48.82%. On VV3 Vmaks the average is X4 = 0.216 m/sec and (X1 and X2) = 0,000 m/sec, the volocity decreases due to the presence of vegetation between X1, X2 and X5 at Q1 = 100%. In Q2 the average VV0 Vmax condition of the flow X1 = 0.477 m/s and X5 = 0.323 m/s between X1 and X5 the volocity decreases due to turn 28.45%. VV3 Vmax conditions on average X5 = 0.312 m / s and X1 = 0.000 m / s, between X1 and X5 the speed decreases due to the presence of 100% vegetation. In connection with the above results, with this research the local community and local government can carry out cleaning on the channel on a scale basis.

scholarly journals Energy Loss in Steep Open Channels with Step-Pools

Water ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 72
Author(s):  
Suresh Kumar Thappeta ◽  
S. Murty Bhallamudi ◽  
Venu Chandra ◽  
Peter Fiener ◽  
Abul Basar M. Baki
Keyword(s):  
Energy Loss ◽  
Flow Rate ◽  
Recirculation Zone ◽  
Three Dimensional ◽  
Nonlinear Function ◽  
Open Channels ◽  
Geometrical Parameters ◽  
Transition Flow ◽  
Cumulative Energy ◽  
Zone Velocity

Three-dimensional numerical simulations were performed for different flow rates and various geometrical parameters of step-pools in steep open channels to gain insight into the occurrence of energy loss and its dependence on the flow structure. For a given channel with step-pools, energy loss varied only marginally with increasing flow rate in the nappe and transition flow regimes, while it increased in the skimming regime. Energy loss is positively correlated with the size of the recirculation zone, velocity in the recirculation zone and the vorticity. For the same flow rate, energy loss increased by 31.6% when the horizontal face inclination increased from 2° to 10°, while it decreased by 58.6% when the vertical face inclination increased from 40° to 70°. In a channel with several step-pools, cumulative energy loss is linearly related to the number of step-pools, for nappe and transition flows. However, it is a nonlinear function for skimming flows.

scholarly journals Efisiensi Penyaluran Air Irigasi BKA Kn 16 Lam Raya Daerah Irigasi Krueng Aceh

2015 ◽  
Vol 8 (1) ◽  
pp. 19-28 ◽  
Author(s):  
Andriani Asarah Bancin ◽  
Dewi Sri Jayanti ◽  
T. Ferijal
Keyword(s):  
Water Resources ◽  
Water Loss ◽  
Irrigation Water ◽  
Water Delivery ◽  
Surface Irrigation ◽  
Secondary Channel ◽  
Irrigation Network ◽  
Irrigation Area ◽  
Average Water ◽  
Delivery Efficiency

Abstrak. Daerah Aliran Sungai (DAS) Krueng Aceh memiliki jaringan irigasi permukaan teknis untuk mengairi 7.450 ha lahan sawah di Kabupaten Aceh Besar. Peningkatan tekanan pada sumber daya air yang tersedia untuk irigasi dan kebutuhan lainnya, terutama selama musim kemarau, membutuhkan jaringan irigasi yang memiliki efisiensi yang tinggi untuk menyalirkan air irigasi. Penelitian ini bertujuan untuk mengetahui efisiensi penyaluran dan jumlah kehilangan air di saluran sekunder dan tersier dari jaringan irigasi pilihan yaitu Jaringan Lam Raya.Hasil penelitian menunjukkan bahwa efisiensi penyaluran rata-rata untuk BKA Kn 16 Lam Raya adalah 52,47%. Rata-rata kehilangan air dan efesiensi penyaluran air di saluran sekunder berturut-turut adalah 0.048 m3/dtk dan 81,11%. Kehilangan tersebut disebabkan oleh penguapan 2,73 x 10-7 m3/dtk, rembesan 0,00212 m3/dtk dan faktor lainnya 0,04548 m3/dtk. Kehilangan air rata-rata di saluran tersier adalah 0.01 m3/dtk yang merupakan kehilangan akibat adanya penguapan 5,046 x 10-8 m3/dtk, rembesan 0,00033m3/dtk dan faktor lainnya 0,00994 m3/dtk. Hal tersebut menyebabkan efisiensi penyaluran air di saluran tersier sekitar 71,88%. Namun, kinerja jaringan irigasi masih dikategorikan baik karena memiliki efisiensi penyaluran air yang lebih besar dari 60%. Kehilangan air di saluran tersier sebagian besar disebabkan oleh banyak bagian dinding dan dasar saluran yang rusak, dan adanya vegetasi dan sedimen pada saluran yang memperlambat aliran air. Conveyance Efficiency Of Irrigation Water At BKA Kn 16 Lam Raya Krueng Aceh Irrigation Area Abstract. Krueng Aceh Watershed has technical surface irrigation network to irrigate 7.450 ha of paddy fields in Aceh Besar District. Increasing pressure on available water resources for irrigation and other needs, particularly during dry season, requires an irrigation network having a higher level of efficiency to deliver irrigation water. This study aims to determine the delivery efficiencies and amount of water loss in secondary and tertiary channels of selected irrigation network. Lam Raya network was selected for the study area. Results showed that average delivery efficiency for BKA Kn 16 Lam Raya was 52.47%. The average water loss and water delivery efficiency in secondary channel were 0,048 and 81,11%, respectively. The loss was caused by evaporation 2.73 x 10-7 m3/s, seepage 0.00212 m3/s and other factors 0.04548 m3/s. The average water loss in tertiary channels was 0,01 m3/s contributed by losses from evaporation 5.046 x 10-8 m3/s, seepage 0.00033 m3/s and other factors 0.00994 m3/s. It caused tertiary channel's water delivery efficiency was approximately 71,88%. However, performance of irrigation network was classified as good since it has water delivery efficiency greater than 60%.  Water loss in tertiary channel largely due to many parts of wall and base of the channels were broken, and the presence of vegetation and sediment in the channel slowed the water flow.

scholarly journals Partisipasi Masyarakat Lokal Dalam Pengelolaan Daya Tarik Wisata Air Terjun Sipiso-piso Kabupaten Karo, Sumatera Utara

2020 ◽  
Vol 8 (2) ◽  
pp. 238
Author(s):  
Louis Steven Sitanggang ◽  
Dian Pramita Sugiarti
Keyword(s):  
Community Organizing ◽  
Local Community ◽  
Local People ◽  
Community Supervision ◽  
Community Based ◽  
Planning Stage ◽  
Tourist Attractions ◽  
District Government ◽  
North Sumatra

Sipiso-piso Waterfall located in Karo District, North Sumatra can be used as a superior attraction because it has great potential to be developed compared to other attractions around Lake Toba because this waterfall is one of the most popular tourist attractions. However, there are several obstacles on the development of Sipiso-piso Waterfall tourism such as tourism stakeholders who do not cooperate well such as the provision of supporting facilities that should be provided by the tour manager, namely the Karo District government instead, provided by the local community. Based on this phenomenon, it is necessary to know the management of Sipiso-piso Waterfall and how much participation of local people in the management of Sipiso-piso Waterfall. The method used in this research is descriptive qualitative. This research aims to To find out how to manage Sipiso-piso waterfall in Karo District, North Sumatra To find out how far the participation of local people in the management of Sipiso-piso waterfall. Data collection techniques using observation, interviews, and literature. Determination of informants using Purposive Sampling techniques. The results of this research is that the  community in the management of Sipiso-Piso Water Tourism Attraction at the planning stage is at the encouraged participation type, at the community organizing stage is at the spontaneous participation as well as at the mobilization stage, while at the community supervision stage is at the encouraged participation type.   Keywords: participation, development, local community

scholarly journals COMMUNITY NURSERY PARTICIPATION FOR AVAILABILITY OF SEEDS IN CANDI REJO VILLAGE BIRU BIRU SUB-DISTRICT DELI SERDANG DISTRICT

2019 ◽  
Vol 4 (1) ◽  
pp. 76-80
Author(s):  
Rahmawaty ◽  
Yunus Afifuddin ◽  
Ridahati Rambey
Keyword(s):  
Community Service ◽  
Wood Species ◽  
Local Community ◽  
Farm Level ◽  
Village Community ◽  
Service Activity ◽  
North Sumatra

The community service activity was conducted in Candi Rejo Village, Biru-biru District, Deli Serdang Regency, North Sumatra Province. This activity aimed to ensure the availability of seeds at the farm level by providing assistance to community nurseries. The types of plants that were seeded such as: coconut, durian, avocado, mindi  and cocoa. The five types of plants were needed by the local community. Agroforestry (combining cocoa and wood species such as mindi, coconut, avocado, durian and others) was a system used by the Candi Rejo Village community.

scholarly journals Physical modelling of energy losses at surcharged three-way junction manholes in drainage system

2021 ◽  
Author(s):  
Q. Li ◽  
J. Xia ◽  
M. Zhou ◽  
S. Deng ◽  
H. Zhang ◽  
...  
Keyword(s):  
Energy Loss ◽  
Flow Structure ◽  
Water Depth ◽  
Drainage System ◽  
Physical Modelling ◽  
Head Loss ◽  
Geometrical Parameters ◽  
Flow Discharge ◽  
Discharge Ratio ◽  
Loss Coefficients

Abstract Motivated by the observation that vortex flow structure was evident in the energy loss at the surcharged junction manhole due to changes of hydraulic and geometrical parameters, a physical model was used to calculate energy loss coefficients and investigate the relationship between flow structure and energy loss at the surcharged three-way junction manhole. The effects of the flow discharge ratio, the connected angle between two inflow pipes, the manhole geometry, and the downstream water depth on the energy loss were analyzed based on the quantified energy loss coefficients and the identified flow structure. Moreover, two empirical formulae for head loss coefficients were validated by the experimental data. Results indicate that the effect of flow discharge ratio and connected angle are significant, while the effect of downstream water depth is not obvious. With the increase of the lateral inflow discharge, the flow velocity distribution and vortex structure are both enhanced. It is also found that a circular manhole can reduce local energy loss when compared to a square manhole. In addition, the tested empirical formulae can reproduce the trend of total head loss coefficient.

scholarly journals Assessment of heavy metal accumulation in tissues of keperas (Cyclocheilichthys apogon Val. 1842) in Lake Lau Kawar, North Sumatra

2021 ◽  
Vol 912 (1) ◽  
pp. 012044
Author(s):  
Wahyudi ◽  
T A Barus ◽  
S Ilyas
Keyword(s):  
Heavy Metals ◽  
Risk Assessment ◽  
Volcanic Ash ◽  
Local Community ◽  
Bioconcentration Factor ◽  
Metal Accumulation ◽  
Heavy Metal Accumulation ◽  
Native Fish ◽  
Fish Resources ◽  
North Sumatra

Abstract Lake Lau Kawar is one of the exposed areas in North Sumatra by the volcanic ash originating from Mount Sinabung eruption. The lake has been utilized as a tourism site and fish resources for consumption by the local community. Keperas (Cyclocheilichthys apogon Val. 1842) is one of the native fish commonly caught by the community. The aim of this study was to determine the levels of selected heavy metals such as copper (Cu), lead (Pb), and zinc (Zn) accumulated by C. apogon and the ones present in the lake water. The results showed that Zn present in the highest concentration followed by Cu and Pb as similar to the results from bioconcentration factor (BCF). All heavy metals (Cu, Pb, Zn) exhibited their highest concentrations in the gills, while the muscles possessed the lowest concentrations of all metals. Risk assessment based on the national and internasional standard revealed that the concentration of these metals was relatively low and safe for consumption.

An Experimental Procedure for Determining Both the Density and Flow Rate From Pressure Drop Measurements in a Cylindrical Pipe

2008 ◽  
Vol 130 (9) ◽  
Author(s):  
Ghislain Michaux ◽  
Olivier Vauquelin ◽  
Elsa Gauger
Keyword(s):  
Reynolds Number ◽  
Flow Rate ◽  
Pressure Change ◽  
Gas Mixture ◽  
Gas Extraction ◽  
Cylindrical Pipe ◽  
Flow Area ◽  
Number Range ◽  
Experimental Procedure ◽  
Pressure Drops

An experimental procedure was developed for determining both the density and flow rate of a gas from measurements of pressure drops caused by an abrupt flow area contraction in a cylindrical pipe. Experiments were carried out by varying the density and flow rate of a light gas mixture of air and helium, spanning a Reynolds number range from 0.2×104 to 3.4×104. From experimental results, a procedure was then proposed for evaluating the density from pressure change measurements in the scope of light gas extraction experiments.

Design Parameters and Practical Considerations in the Two-Phase Forced-Convection Cooling of Multi-Chip Modules

1992 ◽  
Vol 114 (3) ◽  
pp. 280-289 ◽  
Author(s):  
Christopher O. Gersey ◽  
Thomas C. Willingham ◽  
Issam Mudawar
Keyword(s):  
Forced Convection ◽  
Flow Rate ◽  
Rectangular Channel ◽  
Nucleate Boiling ◽  
Design Parameters ◽  
Two Phase ◽  
Chip Surface ◽  
Flow Area ◽  
Convection Cooling ◽  
Two Phase Cooling

Forced-convection boiling was investigated with a dielectric coolant (FC-72) in order to address some of the practical issues related to the two-phase cooling of multi-chip modules. The module used in the present study featured a linear array of nine, 10 × 10 mm2, simulated microelectronic chips which were flush-mounted along a 20-mm wide side of a rectangular channel. Experiments were performed with a 5-mm channel gap (distance between the chip surface and the opposing channel wall) at eight orientations spaced 45 degrees apart. Two other channel gaps, 2 and 10 mm, were tested in the vertical up flow configuration. For all these configurations, the velocity and subcooling of the liquid were varied from 13 to 400 cm/s and 3 to 36°C, respectively. Changes in orientation did not affect single-phase or nucleate boiling characteristics, but did have a major impact on CHF. Upflow conditions were found to be the best configuration for the design of two-phase cooling modules because of its inherently stable flow and relatively high CHF values. The CHF value for the most upstream chip in vertical upflow agreed well with a previous correlation for an isolated chip. Combined with the relatively small spread in CHF values for all chips in the array, this correlation was found to be attractive for design purposes in predicting CHF for a multi-chip array. To achieve a given CHF value, it is shown how the strong CHF dependence on velocity rather than flow area allows for a reduction in the required flow rate with the 2-mm, as compared to the 5-mm gap, which also required a smaller flow rate than the 10-mm gap. This reduction inflow rate was significant only with subcooled conditions corresponding to high CHF values.

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