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2021 ◽  
Vol 24 (4) ◽  
pp. 281-285
Author(s):  
Seyithan Taysi ◽  
◽  
Nour Alafandi ◽  
Elif Demir ◽  
Kadir Çınar ◽  
...  

2021 ◽  
Vol 14 (2) ◽  
pp. 94-98
Author(s):  
Mela Melarizki Rizki ◽  
Muchlisi Nalahuddin ◽  
Riza Muharni

In the Bukittinggi City Hospital building which has 6 floors, there is a water pump and a reservoir used to supply clean water for daily needs. Based on the reality in the field where there is no secondary data to determine the type of pump and reservoir. The purpose of this analysis is to obtain clean water discharge requirements, obtain the type of pump and ensure that the reservoir used for building C RSUD Kota Bukittinggi is in accordance with the type of pipe and reservoir installed in building C, floor 6. By using field studies and interviews and applying the formulas related to pump calculations. In determining the type of pump to be used in the building, it includes the required water discharge, determining the capacity of the components to be used such as pipe diameter, water tank capacity on the ground floor and roof of the building and the total head on the pipe. Based on the calculation results, the required water discharge is 0.08333 m 3 /min, the upper reservoir has a capacity of 150,000 liters, the bottom reservoir is 5,000 liters and the Hot that occurs is 18.429 m. Then the required pump specifications are 40 x 32B2 -51.5 Grundfos CM 10-3. The pump specifications are not much different from those that have been applied in the field.


2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Xiaoming Zhao ◽  
Shiyu Shang ◽  
Yuanlin Yang ◽  
Mingming Hu

The soil hydraulic conductivity of an embankment has strong spatial variability due to the spatiotemporal variation, both natural and artificial. The strong randomness of the hydraulic conductivity can be expressed by the coefficient of variation (COV) and the fluctuation scale θ. Moreover, different coefficients of variation and fluctuation scales correspond to different random field structures. To study the characteristics of the three-dimensional stochastic seepage field in an embankment under different COVs and fluctuation scales, we generate a three-dimensional random field of the hydraulic conductivity of multimedia embankment based on the local average subdivision technique. In particular, a calculation method for a three-dimensional random seepage field based on the Monte Carlo method combined with a three-dimensional multimedia random field and a deterministic analysis is proposed. The results showed that after three thousand realizations and considering the randomness of the hydraulic conductivity, the position of the free surface of each section in the embankment differed. The mean value of the total head decreased when the COV increased. Furthermore, when the COV was small, the change in the total head with anisotropy ratio was not evident, while the COV was large. The mean value of the total head increased with the anisotropy ratio. When the anisotropy ratio increased, the mean value of the standard deviation of the total head increased first and then decreased.


2021 ◽  
Vol 5 (2) ◽  
pp. 101-113
Author(s):  
Wahyu Hidayat ◽  
Damawidjaya Biksono ◽  
Dadan Zulpian

AbstrakPengujian unjuk kerja pompa sentrifugal multistage berkapasitas 118,5 kW di kawasan Pembangkit Listrik Tenaga Panas Bumi (PLTP) daerah Jawa Barat saat ini akan menyesuaikan prosedur standar. Standar pengujian pompa diterapkan pada proses pengujian pompa dengan tujuan nilai hasil pengujian valid. Nilai head dan debit yang didapat dari pengujian dibandingkan dengan hasil pengujian sebelum penerapan standar. Pengujian pompa sentrifugal menerapkan metode pengujian lapangan dengan menerapkan standar ISO 9906-2012. Standar ISO 9906-2012 adalah panduan baku pengujian pompa rotodinamik. Dari hasil pengujian, didapatkan kurva pompa sentrifugal multistage debit maksimal 116,64 m3/h pada head 275,13 m. Pada data spesifikasi kapasitas pompa sebesar 108 m3/jam dan head total sebesar 300 m. Hal ini berarti prosedur pengujian pompa ISO 9906-2012 dapat memungkinkan kita untuk melihat kinerja pompa aktual.Kata kunci: pompa sentrifugal, pengujian lapangan, uji kinerja pompa, ISO 9906  AbstractPerformance test of multistage centrifugal pump at geothermal power plant area around west java is about to adapt standard procedure. Pump testing standards are applied during pump performance test in order to valid test result values. Head and flowrate value from current test compared with previous test result before standard are applied. Pump performance test use field test method by applying ISO 9906-2012 standard. ISO 9906-2012 standard is a normative guidance for rotodynamic pump testing. The test result shows multistage centrifugal pump curve maximum flowrate is 116,64 m3/h at total head 275,13 m. Pump specification sheet shows that maximum capacity is 108 m3/h and total head 300 m. It indicates that ISO 9906-2012 standard pump testing procedure allow us to determine actual pump performance.Kata kunci: Centrifugal pump, field test, performance test, ISO 9906


Author(s):  
Agata Banach ◽  
Grzegorz Neubauer ◽  
Adam Flis ◽  
Mateusz Ledwoń

AbstractThe growth of a nestling during the first few weeks after hatching is crucial for its further life and is sensitive to the conditions experienced during this period. Among species exhibiting Sexual Size Dimorphism (SSD), one of the most important factors influencing growth parameters is the sex of the hatchlings. In this study, we tested whether sex and other factors (hatching date, egg volume, brood size and sex ratio in the brood) were related to sex on growth parameters in Whiskered Tern (Chlidonias hybrida) chicks. In this species, males are 3%–10% larger than females when adult. At hatching, only the total head length was greater in males than females, but values close to fledging were greater for most of the measured parameters (3%—tarsus, 4%—total head length, 13%—body mass). Moreover, the maximum body mass growth rate was higher in males but females entered the rapid growth phase somewhat earlier and achieved the final total head length sooner. Nestling growth was also significantly correlated with brood size and hatching date, though mostly negatively (e.g. lower tarsus and total head length asymptote, lower maximum growth rate and growth rate constant of total head length in bigger and later clutches). The occurrence of SSD during the nestling period and higher maximum growth rate of body mass in males indicates that the costs of raising sons may be higher than of raising daughters. However, we did not find evidence of either sex-biased nestling mortality or skewed sex ratio.


2021 ◽  
Author(s):  
Janneck Harbeck ◽  
Silvio Geist ◽  
Markus Schatz

Abstract Evaporation cooling increases gas turbine power output. Experimental results suggest an 8% increase of power when 1% of the overall mass flow is added via water droplets injected upstream of the compressor. However, water injection has an impact on the flow field, which requires experimental research involving probe measurements in the droplet-laden flow as well as reliable monitoring during operation, as the volumetric flow rate throughout the stages changes notably and deviates from (dry) design parameters. Measuring with a conventional pressure probe in two-phase flows is challenging because the droplet-laden flow can clog the pressure taps, thus effectively separating the sensor from the measurement location. This paper presents a consistent approach to measure stagnation pressure in a droplet-laden flow field. The probe was purged constantly to prevent droplets from clogging the tubing. The recorded pressure is then corrected using a transfer function to account for the purging pressure offset. A detailed description of how to obtain this function is given within the paper. With this setup, the flow field downstream of a blade cascade was measured at several water mass fractions and spray characteristics. The pressure measurements are compared with the usual LDA/PDA measurements in the wake of the cascade. Based on the test results, an evaluation of the change of total-head loss due to water injection and evaporation compared to dry operation can be performed.


Author(s):  
Giuliani Prado ◽  
Rafael R. Bruscagin ◽  
Adriano C. Tinos ◽  
Edmilson C. Bortoletto ◽  
Denise Mahl

ABSTRACT This study aimed to iteratively set the local head loss coefficient of the Naan® micro-sprinkler, model 7110 Hadar, installed in a lateral irrigation line. To evaluate the total head loss along the lateral line, tests were performed using a rigid PVC pipe with an inner diameter of 15.8 mm, 12 m in length, and 24 micro-sprinklers inserted along the pipe, regularly spaced 0.5 m. In the tests carried out for four micro-sprinkler nozzle diameters (0.9, 1.0, 1.1, and 1.2 mm) and six inlet pressure head values (5, 10, 15, 20, 25, and 30 m) in the line, the pressure head difference between inlet and outlet in the pipe and the discharge of each emitter along the pipe were measured. The head loss computation was performed by the step-by-step procedure, starting from the downstream end to the upstream end of the line; since varying the local head loss coefficient values iteratively, the total head loss measured in the tests was equal to the calculated. For the different working conditions of the inlet pressure head and the micro-sprinkler nozzle diameter, the local head loss coefficient had values from 0.051 to 0.169. Relating the discharge values measured and estimated along the lateral line, the confidence coefficient of 0.9991 was verified, and the calculation procedure was considered optimal.


2021 ◽  
Vol 28 (2) ◽  
pp. 135-143
Author(s):  
F. V. Semenov ◽  
R. V. Reznikov ◽  
A. A. Strelyaev

Background. Middle ear neoplasm is a rare pathology accounting for about 0.7% total head and neck tumours. The article describes the clinical presentation, diagnostic methods and surgical treatment for neoplasms of mastoid process, a quite rare tumour localisation.Clinical Case Description. Patient G., 66 yo, was admitted to a otorhinolaryngological unit with a preliminary diagnosis of left mastoid neoplasm and complaints of non-transient headache on the left and slight hearing loss in both ears. The symptoms have been persisting since childhood. Laboratory tests without abnormalities. Voluminous invasive neoplasm of left temporal bone mastoid in CT. Left mastoidectomy with mastoid neoplasm resection was performed routinely, with a histological examination of surgical material. Benign angiofibroma in morbid histology. Definitive diagnosis: neoplasm of left mastoid. Relief from headache and overall improvement were reported by the patient in two months after surgery.Conclusion. Benign mastoid angiofibroma is a rare tumour in terms of localisation and morphology reluctant to diagnosis in an asymptomatic form. We suggest computed tomography as the main diagnostic and surgery — as main treatment method in this pathology. The disease has a life-favourable prognosis.


2021 ◽  
Vol 39 (4) ◽  
pp. 1085-1092
Author(s):  
M.S. Dalero ◽  
N.A. Musa

Water is the primary source of life for mankind and one of the most basic necessities for rural development. Most rural communities in Nigeria do not have access to potable water. This research considers the provision of water to a community in Nigeria using power from wind. The design results show that a 2.076m diameter windmill is required for pumping water from borehole through a total head of 45m to meet a daily demand of 3.5m3 of water. Performance test of the horizontal axis wind pump was carried out. The lowest measured wind speed during the test was 0.4 m/s, while the corresponding water discharge flowrate was 0.032 l/s. Thehighest flowrate of 0.113 l/s was recorded at a wind speed of 2.4 m/s. Computer simulation was carried out to validate the  performance test of the prototype windmill. The results showed that water discharge is proportional to the wind speed. Keywords: Energy, Kpakungu, mean wind speed, plunger, windmill


2021 ◽  
Vol 27 (3) ◽  
pp. 15-32
Author(s):  
Abdullah A. Rihan ◽  
Thamer A. Mohamed ◽  
Dr. Wissam H. Alawee

The flow in a manifolds considered as an advanced problem in hydraulic engineering applications. The objectives of this study are to determine; the uniformity qn/q1 (ratio of the discharge at last outlet, qn to the discharge at first outlet, q1) and total head losses of the flow along straight and rectangular loop manifolds with different flow conditions. The straight pipes were with 18 m and 19 m long and with of 25.4 mm (1.0 in) in diameter each. While, the rectangular close loop configuration was with length of 19 m and with diameter of 25.4 mm (1.0 in) also. Constant head in the supply tank was used and the head is 2.10 m. It is found that outlets spacing and manifold configuration are the main factors affecting the uniformity of flow distribution and friction head losses along manifolds. For large value of outlets spacing, the uniformity coefficient (qn/q1) was found with greatest value of 0.96. Thus, the flow distribution improves with bigger spacing between outlets along manifold. For same manifold length, diameter, inlet head and spacing between outlets (S/L=0.079), the uniformity coefficient was found 0.881 or 88.1% for straight manifold and 0.926 for rectangular loop manifold. From the experimental data, a better uniformity is obtained from the rectangular loop manifold, this is because the friction head loss in rectangular loop manifold was lower than that in straight manifold. The lowest of total head losses was found with greatest outlet spacing along manifold, while the highest of total head losses was found with smallest outlets spacing along manifold. And, the lowest of total head loss was found with the rectangular manifold, while the highest of total head loss was found with the straight manifold.


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