Vanderbilt University Senior Design Project
Fall Semester Report
December 17, 2007
Dr. Andrew Dozier
Dr. A.B. Bonds
Dr. Joel Barnett
TABLE OF CONTENTS
1. SYSTEM OVERVIEW
The primary purpose of the project is to design and fabricate a new intake and/or exhaust system forthe 2008 Formula SAE car.
1.1 Formula SAE
Vanderbilt Motorsports designs and builds an open wheel racecar to compete in the annual Formula SAE competition. Formula SAE is an engineering design competition held in Detroit, MI between 140 colleges and universities. Scoring of the competition is based on both static and dynamic events. The static events include a design presentation, a costpresentation, and a business presentation. The design competition evaluates the overall design of the car. Judges examine every aspect of the car, ranging from weight to materials selection to packaging. The cost competition scores the teams relative to one another with a substantial percentage of scoring for that event based upon a rank relative to the lowest cost score reported. Every teammust submit the actual retail cost of the parts of the car including labor hours and manufacturing. Teams also compete in the business presentation, where the team creates a fictitious marketing plan and presents it to a panel of judges.
The dynamic events are acceleration, skid-pad, autocross, endurance, and fuel economy. The acceleration competition measures the car’s capability in straightline acceleration. The skid-pad times the car around two laps of a figure 8-style track. The autocross track, less than one kilometer long, comprises two laps of hairpin turns, slaloms, and short straight-aways. The endurance course is designed to subject the cars to long, sustained stresses. This track is similar to that of the autocross but is one kilometer long and designed such thatmultiple cars may be on the track at the same time. The competition is run with two drivers, each driving 11 consecutive laps. The fuel economy is measured during the endurance competition. The weighted scoring for each event is displayed in Figure 1.
Figure 1: Percentage of Total Score for Each Event at Formula SAE
The single biggest factor in a team’s overall score is the enduranceevent, comprising 34% of the overall score. Design and cost are also large percentages of a team’s overall score, and the areas where the Vanderbilt team has struggled the most.
1.2 The Car
Each team is allowed to design a unique car within the rule specifications. The 2007 VU Motorsports car is nine feet long, six feet wide and four feet tall. It uses a Honda CBR 600 motorcycle engine havinga displacement of 599cc. The team added high compression pistons to compensate for the restrictor. The car has a steel chassis, a naturally aspirated intake/exhaust system, a sequentially shifting manual transmission, a fiberglass body and an anti-roll system. A picture of the car is located below as Figure 2.
Figure 2: 2007 Vanderbilt Motorsports Car
There are several rulespecifications that directly affect the scope of this project. The design team must take these constraints into account when working toward the final design. Teams must include a 20mm restrictor on their intake systems. This restrictor must be located between the air intake and any forced induction systems. Exhaust noise is limited to 110 dB. In addition, the design team must work under theconstraint that the cost of the system not be substantial for purposes of the overall cost score at the Formula SAE competition.
1.3 The Current System
The 2007 car uses a naturally aspirated intake/exhaust system. The aluminum intake has a fuel rail, spark plug mounts, an air filter mount, a throttle body, and a Venturi-style restrictor. Figure 3 (below) shows a Pro/Engineer rendering of the...