KATA PENGANTAR skripsi Talking Stick Han Depan
ABSTRAK
Fida. Uji Kinerja Mesin Motor Yamaha Vega R 2007 Dengan Berbahan Bakar
Bioethanol dari Limbah Nanas Sebagai Campuran Premium. Skripsi Program
S1 Pendidikan Teknik Mesin Universitas Negeri Surabaya, 2011.
Bertambahnya jumlah kendaraan bermotor diikuti semakin meningkatnya
jumlah konsumsi bahan bakar. Kenyataannya, ketersediaan bahan bakar minyak
bumi semakin mengalami penurunan. Bahan bakar yang berasal dari minyak
bumi tidak bisa diperbaharui. Untuk itu perlu adanya bahan bakar alternatif yaitu
bahan bakar nabati atau bioethanol. Bioethanol diperoleh dari bahan baku limbah
nanas dengan memfermentasi karbohidrat yang terkandung di dalamnya.
Penggunaan bioethanol sebagai bahan bakar pada mesin pembakaran dalam dapat
meningkatkan kinerja mesin.
Jenis penelitian ini adalah eksperimen, obyek penelitian adalah sepeda
motor Yamaha Vega R dan bahan bakar bioethanol. Dengan menggunakan
putaran mesin 3000 rpm-9500 rpm dengan jarak interval 500 rpm. Penelitian ini
menggunakan metode pengujian rpm berubah pada beban penuh ( Full Open
Throttle Valve ) dengan posisi transmisi top gear yang berpedoman pada standart
SAE J 1349 DEC 80. Bahan bakar yang digunakan adalah E0, E2,5, E5, E7,5,
E10, E12,5 dan E15. Teknik analisis yang digunakan adalah analisis deskriptif
yaitu mendeskripsikan data numeric yang diperoleh, kemudian dijelaskan dalam
bentuk kalimat sederhana yang mudah dipahami.
Hasil pengujian menunjukkan bahwa, bahan bakar premium lebih baik
dari pada biopremium (E2,5, E5, E7,5, E10, E12,5 dan E15) dengan campuran
bioethanol dari limbah nanas baik dari segi kualitas maupun kinerja mesin yang
dihasilkan. Hal ini ditunjukkan dengan penurunan torsi masing-masing 12,63 %,
12,48 %, 12,48 %, 12,78 %, 7,78 %, dan 10,72 % pada 5000 rpm. Penurunan daya
masing-masing 7,71 %, 6,45 %, 5,18 %, 5,18 %, 7,71 %, dan 3,79 % pada 7500
rpm. Penurunan konsumsi bahan bakar masing-masing 25,29 %, 24,14 %, 28,74
%, 11,49 %, 27,59 % dan 26,44 % pada 6000 rpm. Penurunan tekanan efektif
rata-rata masing-masing 10,59 %, 10,59 %, 10,59 %, 10,59 %, 5,08 % dan 8,90 %
pada 5000 rpm.
Kata kunci
: Bioethanol, Limbah Nanas, Biopremium, Kinerja Mesin.
i
ABSTRACT
Fida. Test Performance Machine Yamaha Vega R 2007 With Fuel
Bioethanol from Pineapple Waste Mixed As Premium. Thesis Mechanical
Engineering Education Program S1 Surabaya State University, 2011.
Increasing number of vehicles followed the increasing number of fuel
consumption. In fact, the availability of petroleum fuel increasing decline. Fuel
derived from petroleum can not be updated. So that, there is need for alternative
fuels is biofuels or bioethanol. Bioethanol is obtained from pineapple waste of
raw materials to ferment the carbohydrates contained therein. The use of
bioethanol as a fuel in internal combustion engines can improve engine
performance.
This type of research is an experiment, the object of research is a machine
Yamaha Vega R 2007 and bioethanol fuel. By using the engine speed 3000 rpm9500 rpm with range of 500 rpm. This study uses a method of testing changed
rpm at full load (Full Open Throttle Valve) with transmission position top gear is
based on standard SAE J 1349 DEC 80. The fuel used is E0, E2, 5, E5, E7, 5,
E10, E12, and E15. Analytical techniques used is descriptive analysis of
numerical data obtained describe, and then explained in a simple sentence form
that is easy to understand.
Test results show that, premium fuel is better than biopremium (E2, 5, E5,
E7, 5, E10, E12, 5 and E15) with a mixture of bioethanol from pineapple waste in
terms of both quality and performance of the machine produced. This is indicated
by a decrease of torque respectively 12.63%, 12.48%, 12.48%, 12.78%, 7.78%
and 10.72% at 5000 rpm. Loss of power respectively 7.71%, 6.45%, 5.18%,
5.18%, 7.71%, and 3.79% at 7500 rpm. Decrease in fuel consumption respectively
25.29%, 24.14%, 28.74%, 11.49%, 27.59% and 26.44% at 6000 rpm. Decrease in
the average effective pressure respectively 10.59%, 10.59%, 10.59%, 10.59%,
5.08% and 8.90% at 5000 rpm.
Key words: Bioethanol, Pineapple Waste, Biopremium, Performance Machine.
ii
iii
iv
HALAMAN MOTTO DAN PERSEMBAHAN
“Life is Lillahi Ta’ala So We Can Do It Because
Allah Will Blessing As”
“By Gone Be By Gone (Yang Lalu Biarlah Berlalu)”
“Ketika satu pintu tertutup, pintu lain terbuka,
kadang kita menyesali pintu yang tertutup
tersebut terlalu lama dan tak melihat pintu lain
terbuka”
“Ketika Down Ingatlah Terus Perjuangan Ibu,
Karena Ibu Selalu berjuang dan Mendo’akanmu”
Karya ini ku persembahkan untuk ibuku tercinta,
adekku tersayang, pak dhe irfan, seluruh
keluargaku, kak ghofur, Bapak/Ibu Dosen,
seluruh teman-teman di asrama dan seluruh
orang yang mencintaiku dan mendukungku
setiap waktu serta teman-teman yang telah
v
membukakan cakrawala dunia dan
mengingatkanku akan perjuanganku. Bahwa
dengan mendapatkan gelar S. Pd ini akan
menghapus semua air mata ibuku tercinta yang
berada jauh di negeri orang.
“Miss You Mom”
KATA PENGANTAR
Puji syukur alhamdulillah tetap tercurah atas rahmat, hidayah dan inayah
Allah SWT, akhirnya skripsi dengan judul “Uji Kinerja Mesin Motor Yamaha
Vega R 2007 Dengan Berbahan Bakar Bioethanol dari Limbah Nanas
Sebagai Campuran Premium” dapat terselesaikan.
Dalam penyusunan skripsi ini, peneliti mengalami berbagai hambatan dan
kendala. Namun, hal tersebut dapat dilalui karena kerja sama dan motivasi dari
berbagai pihak. Oleh karena itu, peneliti mengucapkan terima kasih dan
penghargaan yang setinggi-tingginya kepada:
1. Kedua orang tua yang senantiasa memberikan motivasi atas kesuksesan saya.
vi
2. Bapak Drs. Ir. I. Wayan Susila, M. T, selaku dosen pembimbing skripsi
Jurusan Pendidikan Teknik Mesin Fakultas Teknik Universitas Negeri
Surabaya.
3. Bapak Drs. Dewanto M.Pd, selaku dosen penguji dan pembahas skripsi dan
Ketua Jurusan Pendidikan Teknik Mesin Universitas Negeri Surabaya.
4. Bapak Drs. Muhaji S. T., M. T, selaku dosen penguji dan pembahas skripsi
Jurusan Pendidikan Teknik Mesin Fakultas Teknik Universitas Negeri
Surabaya.
5. Bapak Ir. Dwi Heru Sutjahjo, M.T., selaku dosen pembimbing dalam
praktikum di Laboratorium Bahan Bakar Dan Pelumas Jurusan Teknik Mesin
Fakultas Teknik Universitas Negeri Surabaya.
6. Bapak Jimmy dan Bapak Komar, selaku karyawan Laboratorium Unit
Produksi Pelumas Surabaya yang telam membimbing dalam pemerolehan data
dan penggunaan alat-alat sesuai ASTM di Laboratorium Pertamina.
7. Bapak Duduh Abdullah, selaku kepala Laboratorium Unit Produksi Pelumas
Surabaya yang telah mengijinkan untuk meneliti di Laboratorium Pertamina.
8. Bapak Drs. Tri Wrahatnolo, M.Pd. Selaku Dekan Fakultas Teknik Universitas
Negeri Surabaya.
9. Bapak Prof. Dr. Muklas Samani, M.Pd. selaku Rektor Universitas Negeri
Surabaya.
10. Seluruh teman-teman yang selalu memberikan motivasi saya.
Peneliti sadar bahwa skripsi ini masih jauh dari sempurna. Seperti pepatah
mengatakan tiada gading yang tak retak, untuk itu peneliti mengharapkan saran
vii
dan kritik yang konstruktif demi kesempurnaan skripsi ini. Akhir kata peneliti
mohon maaf atas segala kesalahan dan kekurangan.
Surabaya, Juni 2011
Peneliti
DAFTAR ISI
Halaman
ABSTRAK.....................................................................................................
i
ABSTRCT......................................................................................................
ii
LEMBAR PERSETUJUAN.........................................................................
iii
LEMBAR PENGESAHAN..........................................................................
iv
HALAMAN MOTTO DAN PERSEMBAHAN.........................................
v
KATA PENGANTAR...................................................................................
vi
DAFTAR ISI..................................................................................................
viii
DAFTAR GAMBAR.....................................................................................
x
DAFTAR TABEL.........................................................................................
xi
BAB I PENDAHULUAN
A.
B.
C.
D.
E.
F.
Latar Belakang....................................................................................
Identifikasi Masalah............................................................................
Rumusan Masalah...............................................................................
Batasan Masalah.................................................................................
Tujuan Penelitian................................................................................
Manfaat Hasil Penelitian.....................................................................
viii
1
5
5
6
7
7
1. Manfaat teoritis............................................................................ .
2. Manfaat praktis.............................................................................
7
8
BAB II KAJIAN TEORI
A. Prinsip kerja motor 4 langkah.............................................................
B. Proses pembakaran motor bensin........................................................
.............................................................................................................13
C. Bahan bakar premium.........................................................................
.............................................................................................................17
D. Bioethanol...........................................................................................
.............................................................................................................19
E. Biopremium........................................................................................
.............................................................................................................22
F. Bioethanol limbah nanas.....................................................................
.............................................................................................................22
1. Nanas.............................................................................................
.......................................................................................................22
2. Karakteristik bioethanol limbah nanas.........................................
.......................................................................................................24
G. Parameter dalam kinerja mesin...........................................................
.............................................................................................................24
1. Daya (power)................................................................................
.......................................................................................................25
2. Torsi (torque)................................................................................
.......................................................................................................25
3. Tekanan efektif rata-rata (Bmep)..................................................
.......................................................................................................26
4. Konsumsi bahan bakar (fc)...........................................................
.......................................................................................................27
9
BAB III METODE PENELITIAN
A. Jenis penelitian....................................................................................
.............................................................................................................29
B. Objek Penelitian..................................................................................
.............................................................................................................29
C. Variabel Penelitian..............................................................................
.............................................................................................................30
D. Waktu dan tempat penelitian..............................................................
.............................................................................................................31
E. Peralatan dan instrumen penelitian......................................................
.............................................................................................................31
F. Prosedur Pengujian.............................................................................
.............................................................................................................35
ix
G. Analisis data........................................................................................
.............................................................................................................37
H. Diagram alur penelitian.......................................................................
.............................................................................................................38
BAB IV HASIL PENELITIAN DAN PEMBAHASAN
A. Hasil Penelitian...................................................................................
.............................................................................................................39
B. Analisis dan Pembahasan....................................................................
.............................................................................................................43
1. Analisis Karakteristik Bahan Bakar..............................................
.......................................................................................................43
2. Analisis Kinerja Mesin.................................................................
.......................................................................................................51
a. Perubahan torsi........................................................................
.................................................................................................51
b. Perubahan daya efektif............................................................
.................................................................................................62
c. Penurunan konsumsi bahan bakar...........................................
.................................................................................................73
d. Penurunan tekanan efektif rata-rata........................................
.................................................................................................85
BAB V SIMPULAN DAN SARAN
A. Simpulan ............................................................................................
.............................................................................................................99
B. Saran...................................................................................................
100
DAFTAR PUSTAKA....................................................................................
LAMPIRAN
x
101
DAFTAR GAMBAR
Nomor Gambar
Halaman
Gambar 2.1 Langkah hisap............................................................................
.........................................................................................................................10
Gambar 2.2 Langkah kompresi......................................................................
.........................................................................................................................11
Gambar 2.3 Langkah ekspansi.......................................................................
.........................................................................................................................12
Gambar 2.4 Langkah buang...........................................................................
.........................................................................................................................13
Gambar 2.5 Pembakaran sempurna udara dan bahan bakar..........................
.........................................................................................................................14
Gambar 2.6 Pembakaran campuran udara dan bensin
terhadap perubahan tekanan di dalam silinder...........................
14
Gambar 2.7 Detonasi.....................................................................................
.........................................................................................................................16
Gambar 2.8 Grafik detonasi motor bensin.....................................................
.........................................................................................................................17
Gambar 2.9. Limbah nanas............................................................................
.........................................................................................................................22
Gambar 2.10 Hasil pengujian motor bensin pada bermacam macam
putaran dengan katup gas terbuka penuh (r=9).........................
27
Gambar 3.1 Skema instrumen penelitian.......................................................
.........................................................................................................................35
Gambar 4.1 Kadar bioethanol vs kandungan timbal.....................................
.........................................................................................................................43
Gambar 4.2 Kadar bioethanol vs distilasi......................................................
.........................................................................................................................44
Gambar 4.3 Kadar bioethanol vs distilasi......................................................
.........................................................................................................................44
Gambar 4.4 Kadar bioethanol vs distilasi......................................................
.........................................................................................................................45
Gambar 4.5 Kadar bioethanol vs distilasi......................................................
.........................................................................................................................45
Gambar 4.6 Kadar bioethanol vs reid vapour pressure (rvp)........................
.........................................................................................................................46
xi
Gambar 4.7 Kadar bioethanol vs getah purwa...............................................
.........................................................................................................................47
Gambar 4.8 Kadar bioethanol vs kandungan sulfur......................................
.........................................................................................................................48
Gambar 4.9 Kadar bioethanol vs kandungan air...........................................
.........................................................................................................................48
Gambar 4.10 Kadar bioethanol vs densitas....................................................
.........................................................................................................................49
Gambar 4.11 Hubungan antara putaran mesin terhadap torsi.........................
.........................................................................................................................52
Gambar 4.12 Hubungan antara putaran mesin terhadap daya efektif.............
.........................................................................................................................63
Gambar 4.12 Hubungan antara putaran mesin terhadap konsumsi bahan
bakar.........................................................................................
74
Gambar 4.12 Hubungan antara putaran mesin terhadap tekanan efektif
rata-rata.....................................................................................
86
DAFTAR TABEL
Nomor Tabel
Halaman
Tabel 1.1 Harga minyak dan gas bumi...........................................................
2
Tabel 2.1 Spesifikasi bahan bakar premium...................................................
.........................................................................................................................18
Tabel 2.2 Sifat fisik ethanol............................................................................
.........................................................................................................................20
Tabel 2.3 Perbandingan sifat ethanol dan gasoline........................................
.........................................................................................................................21
Tabel 2.4 Karakteristik bioethanol dari limbah nanas....................................
.........................................................................................................................24
Tabel 4.1 Perbandingan spesifikasi biopremium berdasarkan data
xii
pertamina dan hasil penelitian........................................................
39
Tabel 4.2 Hasil pengujian torsi berbahan bakar premium murni (E0) dan
campuran premium dengan kadar bioethanol dari limbah nanas
(E2,5, E5, E7,5, E10, E12,5 dan E15)............................................
40
Tabel 4.3 Hasil pengujian daya berbahan bakar premium murni (E0) dan
campuran premium dengan kadar bioethanol dari limbah nanas
(E2,5, E5, E7,5, E10, E12,5 dan E15)............................................
41
Tabel 4.4 Hasil pengujian konsumsi bahan bakar (fc) berbahan bakar premium
murni (E0) dan campuran premium dengan kadar bioethanol
dari limbah nanas (E2,5, E5, E7,5, E10, E12,5 dan E15)..............
41
Tabel 4.5 Hasil pengujian tekanan efektif rata-rata berbahan bakar premium
murni (E0) dan campuran premium dengan kadar bioethanol
dari limbah nanas (E2,5, E5, E7,5, E10, E12,5 dan E15)..............
42
Tabel 4.6 Spesifikasi biopremium..................................................................
.........................................................................................................................50
Tabel 4.7 Penurunan torsi (T).........................................................................
.........................................................................................................................51
Tabel 4.8 Penurunan daya efektif (Ne)...........................................................
.........................................................................................................................62
Tabel 4.9 Penurunan konsumsi bahan bakar (fc)............................................
.........................................................................................................................74
Tabel 4.10 Penurunan tekanan efektif rata-rata..............................................
.........................................................................................................................85
xiii
Fida. Uji Kinerja Mesin Motor Yamaha Vega R 2007 Dengan Berbahan Bakar
Bioethanol dari Limbah Nanas Sebagai Campuran Premium. Skripsi Program
S1 Pendidikan Teknik Mesin Universitas Negeri Surabaya, 2011.
Bertambahnya jumlah kendaraan bermotor diikuti semakin meningkatnya
jumlah konsumsi bahan bakar. Kenyataannya, ketersediaan bahan bakar minyak
bumi semakin mengalami penurunan. Bahan bakar yang berasal dari minyak
bumi tidak bisa diperbaharui. Untuk itu perlu adanya bahan bakar alternatif yaitu
bahan bakar nabati atau bioethanol. Bioethanol diperoleh dari bahan baku limbah
nanas dengan memfermentasi karbohidrat yang terkandung di dalamnya.
Penggunaan bioethanol sebagai bahan bakar pada mesin pembakaran dalam dapat
meningkatkan kinerja mesin.
Jenis penelitian ini adalah eksperimen, obyek penelitian adalah sepeda
motor Yamaha Vega R dan bahan bakar bioethanol. Dengan menggunakan
putaran mesin 3000 rpm-9500 rpm dengan jarak interval 500 rpm. Penelitian ini
menggunakan metode pengujian rpm berubah pada beban penuh ( Full Open
Throttle Valve ) dengan posisi transmisi top gear yang berpedoman pada standart
SAE J 1349 DEC 80. Bahan bakar yang digunakan adalah E0, E2,5, E5, E7,5,
E10, E12,5 dan E15. Teknik analisis yang digunakan adalah analisis deskriptif
yaitu mendeskripsikan data numeric yang diperoleh, kemudian dijelaskan dalam
bentuk kalimat sederhana yang mudah dipahami.
Hasil pengujian menunjukkan bahwa, bahan bakar premium lebih baik
dari pada biopremium (E2,5, E5, E7,5, E10, E12,5 dan E15) dengan campuran
bioethanol dari limbah nanas baik dari segi kualitas maupun kinerja mesin yang
dihasilkan. Hal ini ditunjukkan dengan penurunan torsi masing-masing 12,63 %,
12,48 %, 12,48 %, 12,78 %, 7,78 %, dan 10,72 % pada 5000 rpm. Penurunan daya
masing-masing 7,71 %, 6,45 %, 5,18 %, 5,18 %, 7,71 %, dan 3,79 % pada 7500
rpm. Penurunan konsumsi bahan bakar masing-masing 25,29 %, 24,14 %, 28,74
%, 11,49 %, 27,59 % dan 26,44 % pada 6000 rpm. Penurunan tekanan efektif
rata-rata masing-masing 10,59 %, 10,59 %, 10,59 %, 10,59 %, 5,08 % dan 8,90 %
pada 5000 rpm.
Kata kunci
: Bioethanol, Limbah Nanas, Biopremium, Kinerja Mesin.
i
ABSTRACT
Fida. Test Performance Machine Yamaha Vega R 2007 With Fuel
Bioethanol from Pineapple Waste Mixed As Premium. Thesis Mechanical
Engineering Education Program S1 Surabaya State University, 2011.
Increasing number of vehicles followed the increasing number of fuel
consumption. In fact, the availability of petroleum fuel increasing decline. Fuel
derived from petroleum can not be updated. So that, there is need for alternative
fuels is biofuels or bioethanol. Bioethanol is obtained from pineapple waste of
raw materials to ferment the carbohydrates contained therein. The use of
bioethanol as a fuel in internal combustion engines can improve engine
performance.
This type of research is an experiment, the object of research is a machine
Yamaha Vega R 2007 and bioethanol fuel. By using the engine speed 3000 rpm9500 rpm with range of 500 rpm. This study uses a method of testing changed
rpm at full load (Full Open Throttle Valve) with transmission position top gear is
based on standard SAE J 1349 DEC 80. The fuel used is E0, E2, 5, E5, E7, 5,
E10, E12, and E15. Analytical techniques used is descriptive analysis of
numerical data obtained describe, and then explained in a simple sentence form
that is easy to understand.
Test results show that, premium fuel is better than biopremium (E2, 5, E5,
E7, 5, E10, E12, 5 and E15) with a mixture of bioethanol from pineapple waste in
terms of both quality and performance of the machine produced. This is indicated
by a decrease of torque respectively 12.63%, 12.48%, 12.48%, 12.78%, 7.78%
and 10.72% at 5000 rpm. Loss of power respectively 7.71%, 6.45%, 5.18%,
5.18%, 7.71%, and 3.79% at 7500 rpm. Decrease in fuel consumption respectively
25.29%, 24.14%, 28.74%, 11.49%, 27.59% and 26.44% at 6000 rpm. Decrease in
the average effective pressure respectively 10.59%, 10.59%, 10.59%, 10.59%,
5.08% and 8.90% at 5000 rpm.
Key words: Bioethanol, Pineapple Waste, Biopremium, Performance Machine.
ii
iii
iv
HALAMAN MOTTO DAN PERSEMBAHAN
“Life is Lillahi Ta’ala So We Can Do It Because
Allah Will Blessing As”
“By Gone Be By Gone (Yang Lalu Biarlah Berlalu)”
“Ketika satu pintu tertutup, pintu lain terbuka,
kadang kita menyesali pintu yang tertutup
tersebut terlalu lama dan tak melihat pintu lain
terbuka”
“Ketika Down Ingatlah Terus Perjuangan Ibu,
Karena Ibu Selalu berjuang dan Mendo’akanmu”
Karya ini ku persembahkan untuk ibuku tercinta,
adekku tersayang, pak dhe irfan, seluruh
keluargaku, kak ghofur, Bapak/Ibu Dosen,
seluruh teman-teman di asrama dan seluruh
orang yang mencintaiku dan mendukungku
setiap waktu serta teman-teman yang telah
v
membukakan cakrawala dunia dan
mengingatkanku akan perjuanganku. Bahwa
dengan mendapatkan gelar S. Pd ini akan
menghapus semua air mata ibuku tercinta yang
berada jauh di negeri orang.
“Miss You Mom”
KATA PENGANTAR
Puji syukur alhamdulillah tetap tercurah atas rahmat, hidayah dan inayah
Allah SWT, akhirnya skripsi dengan judul “Uji Kinerja Mesin Motor Yamaha
Vega R 2007 Dengan Berbahan Bakar Bioethanol dari Limbah Nanas
Sebagai Campuran Premium” dapat terselesaikan.
Dalam penyusunan skripsi ini, peneliti mengalami berbagai hambatan dan
kendala. Namun, hal tersebut dapat dilalui karena kerja sama dan motivasi dari
berbagai pihak. Oleh karena itu, peneliti mengucapkan terima kasih dan
penghargaan yang setinggi-tingginya kepada:
1. Kedua orang tua yang senantiasa memberikan motivasi atas kesuksesan saya.
vi
2. Bapak Drs. Ir. I. Wayan Susila, M. T, selaku dosen pembimbing skripsi
Jurusan Pendidikan Teknik Mesin Fakultas Teknik Universitas Negeri
Surabaya.
3. Bapak Drs. Dewanto M.Pd, selaku dosen penguji dan pembahas skripsi dan
Ketua Jurusan Pendidikan Teknik Mesin Universitas Negeri Surabaya.
4. Bapak Drs. Muhaji S. T., M. T, selaku dosen penguji dan pembahas skripsi
Jurusan Pendidikan Teknik Mesin Fakultas Teknik Universitas Negeri
Surabaya.
5. Bapak Ir. Dwi Heru Sutjahjo, M.T., selaku dosen pembimbing dalam
praktikum di Laboratorium Bahan Bakar Dan Pelumas Jurusan Teknik Mesin
Fakultas Teknik Universitas Negeri Surabaya.
6. Bapak Jimmy dan Bapak Komar, selaku karyawan Laboratorium Unit
Produksi Pelumas Surabaya yang telam membimbing dalam pemerolehan data
dan penggunaan alat-alat sesuai ASTM di Laboratorium Pertamina.
7. Bapak Duduh Abdullah, selaku kepala Laboratorium Unit Produksi Pelumas
Surabaya yang telah mengijinkan untuk meneliti di Laboratorium Pertamina.
8. Bapak Drs. Tri Wrahatnolo, M.Pd. Selaku Dekan Fakultas Teknik Universitas
Negeri Surabaya.
9. Bapak Prof. Dr. Muklas Samani, M.Pd. selaku Rektor Universitas Negeri
Surabaya.
10. Seluruh teman-teman yang selalu memberikan motivasi saya.
Peneliti sadar bahwa skripsi ini masih jauh dari sempurna. Seperti pepatah
mengatakan tiada gading yang tak retak, untuk itu peneliti mengharapkan saran
vii
dan kritik yang konstruktif demi kesempurnaan skripsi ini. Akhir kata peneliti
mohon maaf atas segala kesalahan dan kekurangan.
Surabaya, Juni 2011
Peneliti
DAFTAR ISI
Halaman
ABSTRAK.....................................................................................................
i
ABSTRCT......................................................................................................
ii
LEMBAR PERSETUJUAN.........................................................................
iii
LEMBAR PENGESAHAN..........................................................................
iv
HALAMAN MOTTO DAN PERSEMBAHAN.........................................
v
KATA PENGANTAR...................................................................................
vi
DAFTAR ISI..................................................................................................
viii
DAFTAR GAMBAR.....................................................................................
x
DAFTAR TABEL.........................................................................................
xi
BAB I PENDAHULUAN
A.
B.
C.
D.
E.
F.
Latar Belakang....................................................................................
Identifikasi Masalah............................................................................
Rumusan Masalah...............................................................................
Batasan Masalah.................................................................................
Tujuan Penelitian................................................................................
Manfaat Hasil Penelitian.....................................................................
viii
1
5
5
6
7
7
1. Manfaat teoritis............................................................................ .
2. Manfaat praktis.............................................................................
7
8
BAB II KAJIAN TEORI
A. Prinsip kerja motor 4 langkah.............................................................
B. Proses pembakaran motor bensin........................................................
.............................................................................................................13
C. Bahan bakar premium.........................................................................
.............................................................................................................17
D. Bioethanol...........................................................................................
.............................................................................................................19
E. Biopremium........................................................................................
.............................................................................................................22
F. Bioethanol limbah nanas.....................................................................
.............................................................................................................22
1. Nanas.............................................................................................
.......................................................................................................22
2. Karakteristik bioethanol limbah nanas.........................................
.......................................................................................................24
G. Parameter dalam kinerja mesin...........................................................
.............................................................................................................24
1. Daya (power)................................................................................
.......................................................................................................25
2. Torsi (torque)................................................................................
.......................................................................................................25
3. Tekanan efektif rata-rata (Bmep)..................................................
.......................................................................................................26
4. Konsumsi bahan bakar (fc)...........................................................
.......................................................................................................27
9
BAB III METODE PENELITIAN
A. Jenis penelitian....................................................................................
.............................................................................................................29
B. Objek Penelitian..................................................................................
.............................................................................................................29
C. Variabel Penelitian..............................................................................
.............................................................................................................30
D. Waktu dan tempat penelitian..............................................................
.............................................................................................................31
E. Peralatan dan instrumen penelitian......................................................
.............................................................................................................31
F. Prosedur Pengujian.............................................................................
.............................................................................................................35
ix
G. Analisis data........................................................................................
.............................................................................................................37
H. Diagram alur penelitian.......................................................................
.............................................................................................................38
BAB IV HASIL PENELITIAN DAN PEMBAHASAN
A. Hasil Penelitian...................................................................................
.............................................................................................................39
B. Analisis dan Pembahasan....................................................................
.............................................................................................................43
1. Analisis Karakteristik Bahan Bakar..............................................
.......................................................................................................43
2. Analisis Kinerja Mesin.................................................................
.......................................................................................................51
a. Perubahan torsi........................................................................
.................................................................................................51
b. Perubahan daya efektif............................................................
.................................................................................................62
c. Penurunan konsumsi bahan bakar...........................................
.................................................................................................73
d. Penurunan tekanan efektif rata-rata........................................
.................................................................................................85
BAB V SIMPULAN DAN SARAN
A. Simpulan ............................................................................................
.............................................................................................................99
B. Saran...................................................................................................
100
DAFTAR PUSTAKA....................................................................................
LAMPIRAN
x
101
DAFTAR GAMBAR
Nomor Gambar
Halaman
Gambar 2.1 Langkah hisap............................................................................
.........................................................................................................................10
Gambar 2.2 Langkah kompresi......................................................................
.........................................................................................................................11
Gambar 2.3 Langkah ekspansi.......................................................................
.........................................................................................................................12
Gambar 2.4 Langkah buang...........................................................................
.........................................................................................................................13
Gambar 2.5 Pembakaran sempurna udara dan bahan bakar..........................
.........................................................................................................................14
Gambar 2.6 Pembakaran campuran udara dan bensin
terhadap perubahan tekanan di dalam silinder...........................
14
Gambar 2.7 Detonasi.....................................................................................
.........................................................................................................................16
Gambar 2.8 Grafik detonasi motor bensin.....................................................
.........................................................................................................................17
Gambar 2.9. Limbah nanas............................................................................
.........................................................................................................................22
Gambar 2.10 Hasil pengujian motor bensin pada bermacam macam
putaran dengan katup gas terbuka penuh (r=9).........................
27
Gambar 3.1 Skema instrumen penelitian.......................................................
.........................................................................................................................35
Gambar 4.1 Kadar bioethanol vs kandungan timbal.....................................
.........................................................................................................................43
Gambar 4.2 Kadar bioethanol vs distilasi......................................................
.........................................................................................................................44
Gambar 4.3 Kadar bioethanol vs distilasi......................................................
.........................................................................................................................44
Gambar 4.4 Kadar bioethanol vs distilasi......................................................
.........................................................................................................................45
Gambar 4.5 Kadar bioethanol vs distilasi......................................................
.........................................................................................................................45
Gambar 4.6 Kadar bioethanol vs reid vapour pressure (rvp)........................
.........................................................................................................................46
xi
Gambar 4.7 Kadar bioethanol vs getah purwa...............................................
.........................................................................................................................47
Gambar 4.8 Kadar bioethanol vs kandungan sulfur......................................
.........................................................................................................................48
Gambar 4.9 Kadar bioethanol vs kandungan air...........................................
.........................................................................................................................48
Gambar 4.10 Kadar bioethanol vs densitas....................................................
.........................................................................................................................49
Gambar 4.11 Hubungan antara putaran mesin terhadap torsi.........................
.........................................................................................................................52
Gambar 4.12 Hubungan antara putaran mesin terhadap daya efektif.............
.........................................................................................................................63
Gambar 4.12 Hubungan antara putaran mesin terhadap konsumsi bahan
bakar.........................................................................................
74
Gambar 4.12 Hubungan antara putaran mesin terhadap tekanan efektif
rata-rata.....................................................................................
86
DAFTAR TABEL
Nomor Tabel
Halaman
Tabel 1.1 Harga minyak dan gas bumi...........................................................
2
Tabel 2.1 Spesifikasi bahan bakar premium...................................................
.........................................................................................................................18
Tabel 2.2 Sifat fisik ethanol............................................................................
.........................................................................................................................20
Tabel 2.3 Perbandingan sifat ethanol dan gasoline........................................
.........................................................................................................................21
Tabel 2.4 Karakteristik bioethanol dari limbah nanas....................................
.........................................................................................................................24
Tabel 4.1 Perbandingan spesifikasi biopremium berdasarkan data
xii
pertamina dan hasil penelitian........................................................
39
Tabel 4.2 Hasil pengujian torsi berbahan bakar premium murni (E0) dan
campuran premium dengan kadar bioethanol dari limbah nanas
(E2,5, E5, E7,5, E10, E12,5 dan E15)............................................
40
Tabel 4.3 Hasil pengujian daya berbahan bakar premium murni (E0) dan
campuran premium dengan kadar bioethanol dari limbah nanas
(E2,5, E5, E7,5, E10, E12,5 dan E15)............................................
41
Tabel 4.4 Hasil pengujian konsumsi bahan bakar (fc) berbahan bakar premium
murni (E0) dan campuran premium dengan kadar bioethanol
dari limbah nanas (E2,5, E5, E7,5, E10, E12,5 dan E15)..............
41
Tabel 4.5 Hasil pengujian tekanan efektif rata-rata berbahan bakar premium
murni (E0) dan campuran premium dengan kadar bioethanol
dari limbah nanas (E2,5, E5, E7,5, E10, E12,5 dan E15)..............
42
Tabel 4.6 Spesifikasi biopremium..................................................................
.........................................................................................................................50
Tabel 4.7 Penurunan torsi (T).........................................................................
.........................................................................................................................51
Tabel 4.8 Penurunan daya efektif (Ne)...........................................................
.........................................................................................................................62
Tabel 4.9 Penurunan konsumsi bahan bakar (fc)............................................
.........................................................................................................................74
Tabel 4.10 Penurunan tekanan efektif rata-rata..............................................
.........................................................................................................................85
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