# Queena Lastama

## Contents

## Introduction

Perkenalkan saya Queena Lastama dengan NPM 2106636754. Saya adalah mahasiswa Fakultas Teknik.

## Resume Perkuliahan 26 Mei 2023

Pada pertemuan pertama bersama Pak Dai, kita membahas beberapa materi tentang perkenalan kelas Metode Numerik. Pak Dai memberi penjelasan tentang Metode Numerik yang ada di kehidupan sehari - harii. Pak Dai memberitahu bahwa mahasiswa harus memaksimalkan potensi diri kita selagi masih muda dan berusaha semaksimal mungkin untuk memahami apa yang sedang kita pelajari dan kita ikuti selama menajalani kelas perkuliahan. Pak Dai juga memberi study case yang membuat mahasiswa untuk selalu mengingat bahwa segalanya tidak ada yang sempurna dan pasti kecuali Yang Maha Esa.

## Design & Optimization of Pressurized Hydrogen Storage

To design and optimization a hydrogen storage system that works with 8 bar with a capacity of 1 liter and a budget of IDR 500,000, many things must be taken into account. Here are the steps that can be followed:

Choose a storage container: In this case, the best choice is a strong steel storage tube that can withstand high pressure. Carbon steel tubes are the material of choice for hydrogen storage. Make sure that the chosen bottle meets the required pressure and has a minimum capacity of 1 liter.

Calculate the resistance and thickness of the tube: To ensure that the tube can withstand a hydrogen pressure of 8 bar, you must calculate the resistance and thickness required according to the material and the part of the tube chosen. This may include the use of equity and standards established by the governing body or organization.

Select valves and safety devices: Be sure to use pressure-regulating valves and safety devices suitable for the pressure and capacity required. This will help control pressure and prevent tube failure.

Design of the connection system: You will need to create a good connection system between the bottle and other equipment, such as filling or dispensing valves. Make sure the connection method meets safety standards and minimizes the chance of leakage.

Calculation: In order to guarantee the maximum budget of IDR 500,000, it is necessary to make a total cost for all necessary items, including pipes, valves, safety devices and connection systems. Be sure to consider the price of different items and types, as well as shipping and handling charges if necessary.

Upgrading the cost: If the cost exceeds your budget, you can try to upgrade the plan by looking for more affordable options. This can include comparing different brands and suppliers, considering used bottles that are still worth using, or looking for a simple but still good solution.

Consultation with experts: If you do not have sufficient knowledge or experience in the design of hydrogen storage, it is recommended that you contact experts or engineers with experience in this field. They can provide advice and other guidance based on your needs and budget.

It is important to remember that hydrogen storage requires strict safety standards and that poor design or poor quality can create a risk of leakage or failure. Make sure you always follow the laws and regulations that apply to your area.

## Material Choosing

Compressed gas cylinders are commonly made from several materials, depending on the specific application and required properties. The material that will be used in the construction of this hydrogen tank is AISI 304 austenitic stainless steel. Austenitic stainless steel is also one of the primary choices for manufacturers of industrial hydrogen storage.

## Geometry Analysis

**1. Thickness**

import math

def calculate_optimized_thickness(volume, pressure):

yield_strength = 205 # MPa (Megapascal) safety_factor = 2 # Safety factor for design mpa_to_bar = 10 # 1 MPa = 10 bar pressure_mpa = pressure / mpa_to_bar thickness = (volume * pressure_mpa) / (2 * math.pi * yield_strength * safety_factor) thickness_mm = thickness * 1000 return thickness_mm

volume = 1 # Liter pressure = 8 # bar

optimized_thickness = calculate_optimized_thickness(volume, pressure)

# Print the result print(f"The optimized thickness of Stainless Steel for {volume} liter capacity and {pressure} bar pressure is approximately {optimized_thickness:.2f} mm.")

The optimized thickness of Stainless Steel for 1 liter capacity and 8 bar pressure is approximately 0.31 mm

**2. Height, Radius, and Surface Area**

This following Python code calculates the optimized dimensions based on the given capacity of 1 liter and 8 bar of pressure.

import numpy as np from scipy.optimize import minimize

def calculate_surface_area(x):

radius, height = x surface_area = 2 * np.pi * radius * (radius + height) return surface_area

def calculate_volume(x):

radius, height = x volume = np.pi * radius**2 * height return volume

def optimize_cylinder():

initial_guess = [1.0, 10.0] bounds = [(0, None), (0, None)] constraint = {'type': 'eq', 'fun': lambda x: calculate_volume(x) - 1000} # Update volume constraint value to 1000

result = minimize(calculate_surface_area, initial_guess, method='SLSQP', bounds=bounds, constraints=constraint)

print("Optimization Results:") print("Radius: {:.2f} cm".format(result.x[0])) print("Height: {:.2f} cm".format(result.x[1])) print("Surface Area: {:.2f} cm^2".format(result.fun))

optimize_cylinder()

Based on the provided code, the following information can be obtained: the code Optimization Results: Radius: 5.42 cm Height: 10.84 cm Surface Area: 553.58 cm^2

## Cost Analysis

After calculating the surface area, we can determine the cost for the materials used, which are AISI 304 austenitic stainless steel. The cost per unit for 10x10 cm is Rp20.000. Therefore, the total cost for both materials combined is Rp110.716.