Pengaruh Penambahan Etanol Pada Pertalite Terhadap Nilai Oktan dan Karakteristik Pembakaran Droplet

Subarkah, Salim and Ir. Oyong Novareza, S.T., M.T., Ph.D. and Sugiono, S.T., M.T., Ph.D. (2023) Pengaruh Penambahan Etanol Pada Pertalite Terhadap Nilai Oktan dan Karakteristik Pembakaran Droplet. Magister thesis, Universitas Brawijaya.

Abstract

Kendaraan mengalami gerakan vertikal, lateral, dan roll secara terus menerus. Gerakan tersebut terjadi dari benda atau media dengan arah bolak balik dari kedudukannya. Hal tersebut dapat berpengaruh terhadap semua atau sebagian tubuh. Tingkat keselamatan muatan bergantung pada kebiasaan berkendara dan medan jalan. 40% pengemudi truk cenderung mengemudi dengan cara yang sangat berbahaya dan proporsi varians yang dijelaskan dari pengemudi truk yang berpotensi sangat berbahaya (79,76%) jelas lebih tinggi daripada pengemudi truk jenis lain (14,70%˜34,17%). Faktor keselamatan perlu diperhatikan untuk memastikan tercapainya prinsip kesehatan dan keselamatan kerja (K3). Penelitian dilakukan menggunakan metode elemen hingga sistem buah jeruk satu derajat kebebasan. Digambarkan berupa buah jeruk yang mendapat pembebanan eksitasi getaran random berupan kurva power spectral density (PSD G). simulasi dilakukan menggunakan aplikasi Ansys dengan metode analisis getaran random. Analisis modal dibutuhkan untuk memenuhi syarat linieritas dari analisis getaran random. Output analisis berupa nilai probabilitas defleksi obyek terhadap arah vertikal, lateral, dan transversal. Eksitasi getaran random bersifat statistik di alam. Nilai yang muncul sulit diprediksi. Namun dapat diukur. Peneliti melakukan analisis tentang potensi kerusakan produk yang dipengaruhi oleh getaran selama proses pengiriman. Analisis dilakukan dengan menganalisis data hasil simulasi melalui software komputer terkait pengukuran tingkat getaran yang muncul selama proses treatment getaran. Simulasi ini diasumsikan sebagai getaran yang muncul selama proses pengiriman buah. Hasil analisis modal menunjukkan frekuensi natural buah dan mode shapes buah dalam beberapa frekuensi. Hasil analisis modal menunjukkan buah sistem buah jeruk memiliki frekuensi normal sebesar 19,749 Hz. Terdapat nilai participating factor dan effective mass pada tiap mode. Nilai tertinggi participation factor menentukan kecenderungan arah pergerakan massa pada sistem. Sedangkan effective mass menunjukkan besar respon massa terhadap sistem. Total deformasi dapat dijabarkan lebih rinci berdasarkan arah deformasi sumbu X, Y, dan Z. kecenderungan arah deformai tiap sumbu dapat ditentukan berdasarkan nilai participation factor tertinggi. Arah X, Y, dan Z memiliki moda bentuk tersediri dalam merespon eksitasi getaran random Analisis getaran random aplikasi Ansys menyediakan penjabaran hasil yang cukup lengkap. Harga RMS mengukur nilai efektif untuk menghasilkan getaran. Satuan nilai digunakan untuk mengindikasi tingkat keparahan getaran mesin. Buah jeruk merespon eksitasi pada sumbu Y. kecenderungan ini dapat dilihat berdasarkan nilai Root Mean Square (RMS). Pola dominan ditunjukkan oleh susunan buah dengan pembebanan aksial. Berdasarkan hasil penelitan ini dapat disimpulkan bahwa buah jeruk memiliki frekuensi normal dalam mepertahankan posisi setimbangnya. Saat muncul eksitasi getaran random, respon buah muncul melalui deformasi bentuk. Susunan aksial merupakan posisi yang baik untuk mengantisipasi eksitasi yang muncul. Respon terhadap eksitasi menjadi besar apabila buah jeruk berada ada frekuensi kritis.Nilai deformasi terkcil ditunjukkan pada susunan aksial-aksial dengan deformasi maksimum sebesar 31195mm pada frekuensi 0.18 xiv Hz dengan tegangan normal sebesar 0.28 MPa. Diperlukan teknik pengepakan yang optimal memerhatikan sebaran getaran pada bak truk.

English Abstract

During transportation, truck was experienced vertical, lateral and roll movements continuously. The movement occurs from objects or media in alternating directions from its position. It can affect all or part of the body. The level of cargo safety depends on driving habits and road conditions. 40% of truck drivers tend to drive in a very dangerous manner and the proportion of explained variance of potentially very dangerous truck drivers (79.76%) is clearly higher than other types of truck drivers (14.70%˜34.17%). Safety factors need to be considered to ensure the achievement of the principles of occupational health and safety (K3). The study was conducted using the finite element method of one degree of freedom citrus fruit system. It is depicted in the form of an orange which is subjected to a random vibration excitation loading in the form of a power spectral density (PSD G) curve. The simulation was carried out using the Ansys application with the random vibration analysis method. Modal analysis is needed to fulfill the linearity requirements of the random vibration analysis. The output of the analysis is in the form of object deflection probability values in the vertical, lateral and transverse directions. Random vibrational excitations are statistical in nature. The value that appears is difficult to predict. But it can be measured. Researchers conducted an analysis of potential product damage that is affected by vibration during the shipping process. The analysis was carried out by analyzing the simulation results data through computer software related to the measurement of vibration levels that appear during the vibration treatment process. This simulation is assumed to be vibrations that occur during the fruit delivery process The results of the modal analysis show the natural frequency of the fruit and the mode shapes of the fruit in several frequencies. The results of the modal analysis show that the citrus fruit system has a normal frequency of 19.749 Hz. There are participating factor and effective mass values in each mode. The highest value of the participation factor determines the trend towards mass movement in the system. Meanwhile, the effective mass shows the mass response to the system. The total deformation can be described in more detail based on the deformation directions of the X, Y, and Z axes. The trend in the deformation direction of each axis can be determined based on the highest participation factor value. The X, Y, and Z directions have their own shape mode in response to random vibration excitation Random vibration analysis of the Ansys application provides a fairly complete description of the results. The RMS value measures the effective value for generating vibrations. The unit value is used to indicate the severity of machine vibration. Citrus fruits respond to excitation on the Y axis. This trend can be seen based on the Root Mean Square (RMS) value. The dominant pattern is shown by the arrangement of fruit with axial loading. Based on the results of this research, it can be concluded that citrus fruits have a normal frequency of maintaining their equilibrium position. When random vibration excitation appears, the response of the fruit appears through shape deformation. The axial arrangement is a good position to anticipate excitation occurring. The response to excitation becomes greater when the citrus fruit is at a critical frequency. The smallest deformation value is shown in the axial- xvi axial arrangement with a maximum deformation of 31195mm at a frequency of 0.18 Hz with a normal stress of 0.28 MPa. Optimum packing technique is needed considering the distribution of vibrations on the truck bed

Item Type:	Thesis (Magister)
Identification Number:	0422070066
Uncontrolled Keywords:	Transportasi, Getaran, Eksitasi, Deformasi, Defleksi-Transportation, Vibration, exitation, Deformation, Deflection
Subjects:	600 Technology (Applied sciences) > 621 Applied physics > 621.8 Machine engineering
Divisions:	S2/S3 > Magister Teknik Mesin, Fakultas Teknik
Depositing User:	Endang Susworini
Date Deposited:	15 Jun 2023 01:37
Last Modified:	15 Jun 2023 01:37
URI:	http://repository.ub.ac.id/id/eprint/201650

Text (DALAM MASA EMBARGO) Salim Subarkah.pdf Restricted to Registered users only until 31 December 2024. Download (5MB)

Actions (login required)

View Item