Studi Numerik Pengaruh Variasi Jumlah Sudu Dan Debit Pompa Terhadap Medan Aliran Pada Pompa Sentrifugal Dengan Blade Round Leading-Edg

Afnan, Alfian Asyam Nur (2024) Studi Numerik Pengaruh Variasi Jumlah Sudu Dan Debit Pompa Terhadap Medan Aliran Pada Pompa Sentrifugal Dengan Blade Round Leading-Edg. Other thesis, Institut Teknologi Sepuluh Nopember.

Text 5007201241-Undergraduate_Thesis.pdf Download (8MB)

Abstract

Abstrak
Pengembangan pompa industri yang efisien dan ramah lingkungan sangat penting untuk meningkatkan produktivitas dan pertumbuhan industri di Indonesia. Salah satu jenis pompa yang umum digunakan adalah pompa sentrifugal, dengan leading-edge dan jumlah sudu impeller sebagai faktor kunci yang memengaruhi kinerjanya. Bentuk leading-edge mempengaruhi peningkatan head, sedangkan jumlah sudu mempengaruhi losses. Penelitian ini bertujuan mengetahui pengaruh modifikasi leading-edge impeller berbentuk round, variasi jumlah sudu (6, 7, dan 8), dan debit aliran terhadap fenomena aliran fluida menggunakan metode simulasi numerik. Tahapan pre-processing melibatkan pembuatan geometri 3D dan pengaturan model simulasi dengan SolidWorks 2020, serta pembuatan meshing dan pengaturan kondisi batas dengan Ansys Fluent. Tahapan processing menggunakan Fluent 2022 R1 mencakup berbagai langkah seperti check, scale, grid, solver, dan lainnya. Hasil penelitian akan berupa data kuantitatif dan kualitatif pada tahap post-processing, termasuk nilai head, efisiensi, kontur tekanan statis, vektor kecepatan relative, serta jalur dan garis aliran.
Pompa dengan kapasitas aliran yang rendah menyebabkan aliran pada impeller passage tidak stabil, yang memicu gangguan aliran seperti vortex dan separasi, berdampak pada nilai head dan efisiensi. Pada kapasitas rendah, muncul dua pasangan vortex pada impeller passage. Vortex pertama terjadi karena tekanan dinamis yang lemah tidak mengatasi backpressure pada volute, dan vortex kedua timbul di leading-edge akibat aliran memasuki passage dengan negative angle of attack. Jumlah sudu yang lebih banyak membentuk aliran lebih terarah, sedangkan jumlah sudu yang lebih sedikit menyebabkan aliran buruk dan vortex lebih besar, mempengaruhi head dan efisiensi. Leading-edge round dengan profil bluff menghasilkan vortex yang memenuhi hampir setengah impeller passage, fenomena tersebut dapat menyebabkan adanya blockage effect yang sangat mempengaruhi nilai head dan efisiensi pompa pada kapasitas rendah.
Hasil dari penelitian ini menunjukkan bahwa jumlah sudu impeller dan bentuk leadin-edge memiliki pengaruh yang cukup besar terhadap performa pompa sentrifugal. Bertambahnya jumlah sudu dan bentuk leading-edge yang lebih streamline mempengaruhi guidance aliran yang membaik. Efisiensi tertinggi didapatkan nilai pada jumlah sudu 8 dan kapasitas 10,8 m3/h dengan bentuk leading-edge round. Nilai efisiensi yang didapatkan sebesar 81,7% dan nilai head sebesar 12,28 m. Perbandingan leading-edge round, terlihat bahwa bentuk leading-edge round lebih sukar untuk mengatasi adanya vortex pada kapasitas rendah dan memiliki head yang lebih rendah pada kapasitas aliran rendah jika dibandingkan dengan bentuk leading-edge sharp.

Kata kunci: Pompa Sentrifugal, Leading-edge, Jumlah Sudu, Debit, Simulasi Numerik
========================================================================================================================
Abstract

The advancement of efficient and environmentally friendly industrial pumps is crucial for enhancing productivity and fostering industrial growth in Indonesia. One of the most commonly utilised types of pump is the centrifugal pump, with the number of impeller blades and the design of the leading edge being of particular significance in determining its performance. The configuration of the leading edge influences the head increase, while the number of blades affects the losses. The objective of this study is to ascertain the impact of modifying the impeller leading-edge to a rounded shape, varying the number of blades (6, 7, and 8), and altering the flow discharge on fluid flow phenomena through the utilisation of a numerical simulation method. The initial phase of the process, designated as the pre-processing stage, entails the creation of a three-dimensional geometry and the configuration of the simulation model using the SolidWorks 2020 software. Additionally, the meshing and establishment of boundary conditions are conducted with the Ansys Fluent software. The processing stage utilises Fluent 2022 R1, comprising a series of steps, including verification, scaling, grid generation, solution, and others. The research outcomes will be presented in the form of quantitative and qualitative data at the post-processing stage, encompassing head values, efficiency, static pressure contours, relative velocity vectors, and flow paths and lines.
A low flow rate impeller will experience unstable flow within the impeller passage, which in turn will cause vortex and separation disturbances, resulting in a reduction in head value and overall efficiency. At low capacity, two vortex pairs are observed in the impeller passage. The first vortex occurs due to the insufficient dynamic pressure to overcome the backpressure on the volute, while the second vortex arises at the leading edge as a result of the negative angle of attack experienced by the flow as it enters the passage. An increase in the number of blades results in a more directed flow, whereas a reduction in the number of blades leads to an inferior flow and a larger vortex, which affects the head and efficiency. A leading-edge round with a bluff profile generates a vortex that occupies approximately half of the impeller passage, which can cause a blockage effect that significantly impacts the head and efficiency of the pump at low capacities.
The results of this study show that the number of impeller blades and the shape of the leading-edge have a considerable influence on the performance of centrifugal pumps. Increasing the number of blades and a more streamlined leading-edge shape affect the improved flow guidance. The highest efficiency is obtained at the number of blades of 8 and a capacity of 10.8 m3/h with a round leading-edge shape. The efficiency value obtained is 81.7% and the head value is 12.28 m. Comparing the leading-edge round, the leading-edge round shape is more difficult to overcome the vortex at low capacity and has a lower head at low flow capacity when compared to the leading-edge sharp shape.

Keywords: Centrifugal Pump, Leading-edge, Number of Blades, Discharge

Item Type:	Thesis (Other)
Uncontrolled Keywords:	Pompa Sentrifugal, Leading-edge, Jumlah Sudu, Debit, Simulasi Numerik, Centrifugal Pump, Leading-edge, Number of Blades, Discharge
Subjects:	T Technology > TJ Mechanical engineering and machinery > TJ903 Pumping machinery. T Technology > TJ Mechanical engineering and machinery > TJ919 Centrifugal pumps--Design and construction.
Divisions:	Faculty of Industrial Technology and Systems Engineering (INDSYS) > Mechanical Engineering > 21201-(S1) Undergraduate Thesis
Depositing User:	Alfian Asyam Nur Afnan
Date Deposited:	12 Aug 2024 03:25
Last Modified:	12 Aug 2024 03:25
URI:	http://repository.its.ac.id/id/eprint/114261

Actions (login required)

View Item