PETUNJUK

PRAKTIKUM

HIDROLIKA

FAKULTAS TEKNIK JURUSAN TEKNIK

SIPIL

UNIVERSITAS ISLAM SULTAN

AGUNG

SEMARANG

i

2014

KATA PENGANTAR

Praktikum Hidrolika (TSG 2318P) merupakan kegiatan mahasiswa pada Semester III.

Melengkapi dalam mendalami materi mata kuliah Mekanika Fluida dan Hidrolika II (TSG

2317).

Kegiatan praktikum terdiri dari dua bagian, untuk sistem saluran terbuka atau open

channels dan sisten saluran tertutup atau pipa. Praktikum saluran terbuka dilaksanakan di luar

sebelah Utara, sedangkan untuk saluran tertutup dilakukan dalam gedung di sebelah selatan.

Praktikum pada saluran terbuka memberikan pengalaman bagi para mahasiswa untuk:

1. Mengukur kecepatan aliran dengan current meter

2. Membaca debit aliran pada alat ukur (cippoletti dan romijin)

3. Membandingkan besar debit dari pembacaan alat ukur dan perhitungan (hasil kali

kecepatan luas penampang saluran)

Sedangakan dari praktikum saluran tertutup mahasiswa akan mendapatkan

pengalaman utamanya mengenai besarnya kehilangan energi:

1. Akibat gesekan antara air dan dinding pipa

2. Akibat perubahan penampang pipa, belokan, perubahan aliran, dan adanya diafragma

Sumber air untuk praktikum diambil dari kolam/ rawa yang ada dekat lokasi dengan

menggunakan pompa air. Kemudian setelah melewati jaringan pipa dan sistem saluran

terbuka aliran air kembali ke rawa.

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DAFTAR ISI

HALAMAN JUDUL...........................................................................................................i

KATA PENGANTAR.........................................................................................................ii

DAFTA ISI..........................................................................................................................iii

DAFTAR TABEL...............................................................................................................v

DAFTAR GAMBAR...........................................................................................................vi

DAFTAR LAMPIRAN.......................................................................................................vii

1. HIDROLIKA BANGUNAN PENGUKUR DEBIT................................................1

1.1 Energi Spesifik..................................................................................................1

1.2 Aliran Modular.................................................................................................2

1.3 Koefisien Pengaliran.........................................................................................3

2. BANGUNAN PENGUKUR DEBIT.......................................................................3

2.1 Umum ...............................................................................................................3

2.2 Alat Ukur Ambang Lebar.................................................................................4

2.2.1 Alat Ukur Romijin ..................................................................................5

2.2.2 Alat Ukur Ambang Lebar dengan Mulut Dibulatkan..............................6

2.2.3 Alat Ukur Ambang Lebar Bentuk Segi Empat........................................6

2.3 Alat Ukur Ambang Tajam................................................................................7

2.3.1 Alat Ukur Cipoletti..................................................................................8

2.3.2 Alat Ukur Rehbock..................................................................................9

2.4 Alat Ukur Ambang Pendek...............................................................................10

2.5 Alat Ukur Parshall............................................................................................10

2.6 Orifis.................................................................................................................12

2.6.1 Venturimeter............................................................................................13

2.6.2 Pintu Sorong............................................................................................14

2.6.3 Crump de Gruyter....................................................................................15

3. PENGUKURAN DEBIT SALURAN TERBUKA.................................................16

3.1 Cara Pengukuran Debit.....................................................................................16

3.2 Pengukuran Langsung......................................................................................16

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3.2.1 Bangunan Ukur Cipoletti........................................................................16

3.2.2 Bangunan Ukur Parshall..........................................................................16

3.2.3 Bangunan Ukur Romijin.........................................................................17

3.3 Pengukuran Tidak Langsung............................................................................17

3.3.1 Pengukuran Kecepatn Vertikal................................................................18

3.3.2 Pengukuran Debit....................................................................................19

3.3.3 Cara Pengukuran dengan Current Meter.................................................21

4. SALURAN TERTUTUP.........................................................................................23

4.1 Latar Belakang Praktikum Saluran Tertutup....................................................23

4.2 Maksud dan Tujuan..........................................................................................23

4.3 Lokasi Praktikum..............................................................................................23

4.4 Landasan teori...................................................................................................23

4.4.1 Piezometer...............................................................................................24

4.4.2 Venturimeter............................................................................................24

4.4.3 Bilangan Reynolds..................................................................................25

4.4.4 Diagram Moody......................................................................................25

4.4.5 Kehilangan Tenaga Aliran Melalui Pipa.................................................26

4.5 Persamaan Tahanan Gesek Pipa.......................................................................27

4.6 Belokan Pipa.....................................................................................................30

4.7 Pelaksanaan Praktikum.....................................................................................32

4.7.1 Tata Cara Pelaksanaan............................................................................32

DAFTAR PUSTAKA..........................................................................................................

LAMPIRAN........................................................................................................................

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DAFTAR TABEL

4.1 Tingkat Kekerasan Pipa..................................................................................26

4.2 Koefisien fb Sebagai Sudut Belokan..............................................................30

4.3 Koefisien fb dan nilai R/D..............................................................................31

4.4 Data Praktikum Aliran Pada Pipa I................................................................33

4.5 Data Praktikum Aliran Pada Pipa II...............................................................34

4.6 Data Praktikum Ketinggian Hidraulik Air Pada Pipa I..................................34

4.7 Data Praktikum Ketinggian Hidraulik Air Pada Pipa II.................................35

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DAFTAR GAMBAR

1.1 Grafik Energi Spesifik....................................................................................1

1.2 Profil Aliran Di Atas Ambang Leher.............................................................3

2.1 Dimensi Ambang Lebar.................................................................................4

2.2 Dimensi Alat Ukur Romijin...........................................................................5

2.3 Dimensi Alat Ukur Ambang Lebar Muka Dibulatkan...................................6

2.4 Dimensi Ambang Lebar Segi Empat..............................................................7

2.5 Dimensi Alat Ukur Ambang Tajam...............................................................8

2.6 Dimensi Alat Ukur Cipoletti..........................................................................8

2.7 Alat Ukur Rehbock.........................................................................................9

2.8 Alau Parshall Flumes......................................................................................11

2.9 Alat Ukur Orifis..............................................................................................12

2.10 Alat Ukur Venturimeter..................................................................................13

2.11 Alat Ukur Pintu Sorong..................................................................................14

2.12 Alat Ukur Crump de Gruyter..........................................................................15

3.1 Bangunan Ukur Tipe Parshall Flume.............................................................17

3.2 Bangunan Ukur Romijin................................................................................17

3.3 Alat Ukur Current Meter................................................................................18

3.4 Bangunan Mid Section...................................................................................20

3.5 Bangunan Mean Section.................................................................................20

3.6 Distribusi Kecepatan Arah Vertikal...............................................................22

3.7 Diagram Perhitungan Debit............................................................................22

4.1 Ventuimeter....................................................................................................25

4.2 Penurunan Rumus Darcy-Weisbach...............................................................27

4.3 Tahanan Gesek Pipa.......................................................................................28

4.4 Pengecilan Pipa..............................................................................................29

4.5 Pengecilan Penampang Berangsur-angsur.....................................................30

4.6 Belokan Pipa...................................................................................................31

4.7 Instrumen Kehilangan Energi Pada Aliran Pipa.............................................32

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DAFTAR LAMPIRAN

Lampiran 1...............................................................................................................

Lampiran 2...............................................................................................................

Lampiran 3...............................................................................................................

Lampiran 4...............................................................................................................

Lampiran 5...............................................................................................................

Lampiran 6...............................................................................................................

Lampiran 7...............................................................................................................

Lampiran 8...............................................................................................................

Lampiran Tabel Debit Cipoletti...............................................................................

Lampiran Tabel Debit Romijin................................................................................

Lampiran Tabel Debit Parshall Flums.....................................................................

Lampiran Bagan Pengukur Debit............................................................................

Lampiran Tabel Mitskot Cipoletti...........................................................................

vii

DAFTAR PUSTAKA

Bambang Triatmodjo, Hidrolika I & II, Beta Offset, Yogyakarta

Chow V.T., Open Channel Hydraulics (Hidrolika Saluran Terbuka), Terjemahan,

Erlangga, Jakarta, 1989

Chaundhry M.H., Open Channel Flow, Prentice Hall, 1993

Fox J.A., an Introduction to Engineering Fluid Mechanics, The Macmillan Press Ltd.

London

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