Temperature Effects on Pressure Vessels

Explore the design process, equations, results and MATLAB code by clicking the link below. Join EngineerX in advancing rocket engineering innovation! 

Temperature Effects on Pressure Vessels.pdf

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Temperature Effects on Pressure Vessels 

In this MATLAB project, I calculate the maximum pressure capacity of 6061-T6 aluminum tubes, vital for rocket pressure vessels and propulsion systems, across temperatures (20–200°C) and inner diameters (4–10 inches). Using hoop and longitudinal stress principles, I ensure robust designs. Below is the methodology, key results, and resources. Full details are in the downloadable methodology and MATLAB code PDFs. 

The Design Challenge 

The aim is to design safe pressure vessels for rocket propulsion and fuel systems by balancing material properties, geometry, and operating conditions. For 6061-T6 tubes with adjustable wall thickness (default 0.1875 inches), I computed the maximum pressure at varying temperatures and IDs, using a 1.8 safety factor. Hoop stress governs, with longitudinal stress as a check, ensuring thin-wall validity for lightweight rocket pressure vessels. 

Process Overview 

The MATLAB script calculates maximum pressure and visualizes results for rocket applications: 

• Define Parameters: Set material (6061-T6), temperatures, yield strengths (21,025–40,000 psi), adjustable wall thickness, safety factor, and ID range. 

• Allowable Stress: Divide yield strength by safety factor per temperature to ensure vessel integrity. 

• Geometry: Compute outer diameter and mean radius, checking thin-wall assumption (OD/t > 10) for rocket vessel optimization. 

• Hoop Stress: Calculate maximum pressure (σ_h = P * r / t) to withstand internal propellant pressures. 

• Longitudinal Stress: Verify with longitudinal stress (σ_l = P * r / (2t)), using the lower pressure. 

• Iterate: Evaluate pressure for 100 IDs to cover a range of rocket vessel sizes. 

• Visualize: Plot pressure vs. ID per temperature, with dynamic titles for design clarity. 

• Specific Case: Compute pressure for ID = 7 inches, a typical rocket vessel size. 

Warnings flag thin-wall assumption violations to ensure reliable designs. 

Key Outcomes 

For ID = 7 inches, wall thickness = 0.1875 inches, safety factor = 1.8: 

• 20°C: Yield Strength = 40,000 psi, Max Pressure = 1,263.16 psi 

• 100°C: Yield Strength = 35,000 psi, Max Pressure = 1,105.26 psi 

• 200°C: Yield Strength = 21,025 psi, Max Pressure = 664.47 psi 

Plots show pressure decreasing with ID and temperature. Adjusting wall thickness optimizes designs for rocket pressure vessel requirements. 

Takeaway 

My MATLAB tool empowers engineers to design safe, lightweight pressure vessels for rocket propulsion and fuel systems. By sharing this methodology and code, EngineerX aims to fuel innovation in rocket engineering.