COMPOSITE MECHANICS
PROJECT REPORT
Bialystok University Of Technology
Yusuf Cingöz
May 2022
Abstract
This report contains inspection of composite connections between two different composite materials. I analyzed and documented this project with FEM
applications.
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Contents
1 STRUCTURAL ANALYSIS OF COMPOSITE FRONT WING
CHASSIS CONNECTIONS
1.1 Drawing The CAD Design Of The Front Wing . . . . . . . . . .
1.2 Importing Geometry To The Ansys Wokbench . . . . . . . . . .
1.3 Creating The Sandwich Panel Material On Ansys Workbench
ACP Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Defining The Boundry Conditions For The Analysis . . . . . . .
1.5 Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.6 Result . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Introduction
What Is Formula Student?
Formula Student is an international engineering design competition first held
by the Society of Automotive Engineers in 1979. The goal is to develop and
provide a platform for student engineers to experience, build, and learn. It
offers a unique way to test students’ theoretical knowledge in a practical context.
Students gain and develop skills such as engineering, project management and
team work. Points are earned in a series of off track, ”Static” events, and
on track, ”Dynamic” events. The team with the most points at the end of
the competition wins. The growing popularity of the competition is proven by
the rapidly rising number of participants and the establishment of new events.
Since the inaugural competition in 1979, the Formula Student competitions
have developed into an international competition with participants from over
20 different countries and over 600 universities.
Aerodynamic Devices Of The Formula Student
Car
Formula Student cars compete in circuits with many tight corners and without
long straights. For this reason, the cars are developed to reach maximum accelerations. This means that the maximum speed of most of the Formula Student
cars is around 120 kph. But in terms of accelerating from 0 to 100 kph, some
Formula Student cars are even faster than Formula One cars. These circumstances dictate the main targets of the aerodynamical development. Because of
relatively low speeds and the high power of Formula Student cars, drag doesn’t
affect the overall performance of the car as much as it does, for example, in
endurance racing or Formula One. In most of the cases, the lap times become
shorter with more downforce, even if the overall aerodynamical efficiency decreases. As mentioned above, the Formula Student circuits are full of corners.
At the same time, because the speeds aren’t very high, crosswind and yaw angle
can become a big factor. This means that most of the time, the aerodynamic
devices must perform in situations where the car isn’t moving straight through
the air. With the amount of downforce, certain amount of load will be placed
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on the aerodynamic devices. In this project, I will inspect the effects of pressure
on the composite front wings connection with the chassis. For doing this, I will
draw a front wing on CATIA and I am going to analys it on Ansys Workbench.
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Chapter 1
STRUCTURAL
ANALYSIS OF
COMPOSITE FRONT
WING CHASSIS
CONNECTIONS
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1.1
Drawing The CAD Design Of The Front Wing
At the beginning of the project, I needed to draw a CAD model of the formula
student type of front wing to run analysis on it. I drew a potential front wing
of a formula student car using CATIA V5. Here is the drawings:
1.2
Importing Geometry To The Ansys Wokbench
This part is one of the most tricky part of the whole project. Because we can
not create sandwich panels on solid models. We should draw our CAD part
as a surface model without thickness. For this project, I only drew connection
parts as a surface model because I only going to use sandwich panels on them.
I drew the main flag as a solid model. I imported the CAD model in two parts
one is for surface and sandwich panel and other one is for foam material which
is for main flap. After two seperated geometries I combined the to the static
structural module in Ansys Workbench. Here is the some screenshots from the
geometries and combinations:
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Surface model that I seperated from main geometry without thickness
Solid model of main flap that I determined as foam.
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1.3
Creating The Sandwich Panel Material On
Ansys Workbench ACP Module
This part is one of the most tricky part of the whole project. Because we can
not create sandwich panels on solid models. We should draw our CAD part
as a surface model without thickness. For this project, I only drew connection
parts as a surface model because I only going to use sandwich panels on them.
I drew the main flag as a solid model. I imported the CAD model in two parts
one is for surface and sandwich panel and other one is for foam material which
is for main flap. After two seperated geometries I combined the to the static
structural module in Ansys Workbench. Here is the some screenshots from the
geometries and combinations:
Fabric.1 is carbonfiber prepreg, Fabric.2 is foam.
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After this phase we need to determine our rosettes for the direction of the
rainforestment.
After this step, we need to define solid model. After defining solid model,
we can close this module and go on.
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In this phase, I assigned flap material as a PVC Foam. After all, I combined
these two sections to static structural module.
After combining, I contuniued the analysis on static structural module.
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As you can see here, we can see our two geometries combined together.
1.4
Defining The Boundry Conditions For The
Analysis
Since my project is inspecting the deformation between chassis and front wing
connections, I need to fix some points and these points ofcourse will be the
connection holes.
After defining fixed supports, I need to define pressure to the main flap.
Pressure value is avarage of the general CFD simulations that I researcehd from
the arcticles. That value will be 75 pascals.
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After defining boundry conditions, I went to the solution section.
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1.5
Solution
Equivilent(von-Mises) Stress
Total Deformation
Equivilent(von-Mises) Stress around the connection points of the front wing
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1.6
Result
After analysis we can say that composite sandwich panel is the one of the
strongest and the lightest options for the racing cars. Lightness and the lateral
strength of the material is makes this material very suitable for the racing.
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