Supersonic Knights

Cody Kaliski

Francisco Martinez

Joseph Rad

Tusya Singh

Due Date: 22 November, 2022

Professor: Dr. Seetha Raghavan

Introduction:

Thin plate analysis is a significant factor for structural analysis on various aircrafts in the modern world. In this project, we aim to determine the significance of thin-plates in the structure of the aircraft. From this, the variety of loading and small deflection conditions can be investigated, to further understand the impact of thin-plates in aircraft structural engineering. These conditions give insight into the responsibilities in structural engineering, and the importance of preserving aircraft integrity and ensuring safety, which will be the top priority of someone in the field. With the calculations, the thin-plate can be subjected to a bending moment and operating uniform. The bending moments are positive in the compressive state at the upper plate surface and in tension at the lower component.

In aerospace structural engineering, it is evident that these thin-plate structures, composed of lightweight components, can support large loads. In this project we are going to use the Lockheed YF-22 wing as our model (Fig. A). This supersonic aircraft will undergo extreme loads on its wings. Utilizing Solidworks to create a 3-D Model of the wing, we will import the model to ANSYS for analysis. ANSYS will be a replacement for NX Nastran, due to the software’s ease of access compared to Nastran, and its capabilities as a CFD tool can be used to further verify the results. This process is followed by real engineers; these simulations must be run before manufacturing and testing of the aircraft.

ANSYS has the ability to determine various aspects of our model, such as deformation and stress on the wing from the loads impacted on it. This software also can be used to change multiple variables to see what will work best for structural integrity as well as weight reduction over the entire figure. From there the use

of CFD allows the comparison between max deformation and deformation at a given speed and load factor, which can be used to see how the solution varies from different types of analysis.

Thin Plate Tutorial:

Within this project one of the tasks assigned was to find the max deflection of a thin plate that was constructed using NX Nastran, as seen in Figure C. This plate was made using the tutorial found on webcourses, which shows a maximum deflection of 1.734 inches when 100 psi of pressure is applied. As seen in the figure, this displacement is at the center with little

to no displacement at the edges. Because of this, we can assume that the plate is simply supported at the edges and the pressure is uniformly distributed across the entire plate. Because of this, you can use the equation shown below:

In order to solve this equation, a basic Octave code was built to make sure that our calculations were accurate. The code for this is shown below:

The idea behind this code is to solve for our values as a 2D array which can be further simplified into a single value, which can be seen in the workspace shown below:

Within this workspace there are two main variables: w_max and w_final. w_max is the individual values for each summation which, when added together, creates w_final. This makes the calculated maximum deflection to be 1.7288 inches, which is extremely similar to the 1.734 inches we found in NX Nastran. Small differences like this make sense as NX Nastran uses approximations of elements within a differential point of reference versus our hand calculations which take into account ideal situations within a geometric point of reference.