P16121: SAE Aero Aircraft Design & Build

System Level Design Review

Project Review Needs and Requirements Review Functional Decomposition Concept Development Concept Selection Initial Risk Identification Feasibility Analysis Engineering Analysis Risk Review Further Work Done Questions

Agenda

RIT Aero Design Club has been absent from the SAE Aero competition (Regular Class) since 2008◦ Prior to 2008, RIT had been inconsistent in participating in the

competition annually

Lacking…◦ Experienced veterans to lead/guide the club◦ Aeronautical engineering experience/knowledge◦ Full commitment as students are on co-op for parts of the year◦ Funding

Current State

Deliverables◦ A functional finished aircraft designed and built to SAE Aero standards◦ Comprehensive documentation of design, build, and testing methods and

processes

Jumpstart the Aero Club◦ Build competence through sharing experience from the present Senior Design

project◦ Desired State: Aero Design club is able to compete in the SAE Aero Competition

annually and be competitive

Desired State/Deliverables

SAE Aero Organization – Primary Customer

RIT Aero Design Club

MSD I Team Members

Dr. Kolodziej – Faculty Guide

RIT Aerospace Engineering Faculty

Potential Sponsors

Rochester Institute of Technology

Stakeholders

Needs and Requirements Review

The competition rules are fulfilling the role of our customer.

The 2015 rules were used for determining the customer requirements.

The 2016 competition rules were published recently. The differences are of minimal consequence for this class of competition. Revision of customer requirements, engineering requirements and the house of quality is a work in progress.

The Customer

Customer Requirements

Importance Key: 3=must have, 2=nice to have, 1=preference only

Engineering Requirements

Importance Key:

9 = Critical3 = Moderate1 = Insignificant

*Note: All engineering requirements derived from SAE Aero rules are deemed critical as failing to meet the target values will result in penalization or disqualification.

House of Quality

Constraints

Functional Decomposition

Functional Decomposition: Part 1

Take-off within required distance

Obtain required initial velocity

Obtain required lift

Utilize control surfaces

Thrust engine (max)

Deploy flaps

Rotate elevator (-)

Utilize 6 cell (22.2 volt) Lithium Polymer (Li-Poly/Li-Po) battery

Decrease Velocity

Obtain required lift

Eliminate engine thrust

Pitch aircraft up (drag increase)

Rotate elevator (-)

Utilize control surfaces

Deploy flaps

Trim aircraft (longitudinal, directional, lateral)

Utilize control surfaces

Rotate elevator as required

Rotate rudder as required

Rotate ailerons as required

Land within required distance

The Aircraft: Fly a required flight path while carrying a payload.

Functional Decomposition: Part 2

Maneuver in flight

Maintain cruise velocity

Obtain required lift

Thrust engine as required

Trim aircraft

Utilize control surfaces

Rotate elevator as required

Rotate rudder as required

Deflect ailerons as required

Utilize 6 cell (22.2 volt) Lithium Polymer (Li-Poly/Li-Po) battery

Control Aircraft

Turn directionally

Pitch aircraft

Roll Aircraft

Rotate elevator as required

Rotate rudder as required

Deflect ailerons as required

Carry payload

Utilize payload bay

Attach to aircraft in a manner that it is easily loaded and removed

The Aircraft: Fly a required flight path while carrying a payload.

Dynamic System Architecture

Concept Development

Benchmarking

Morphological Chart

Possible Solutions Schematics

Solution 1

Solution 2

Solution 3

Solution 4

Solution 5

Solution 6

Solution 7

Concept Selection

Pugh Selection Chart

Datum:University of

Manitoba 2014 Aircraft

There are a few risk areas that we identified for close consideration:

◦ Cost. Can we procure the necessary materials within our $500 budget? What can we do to lower our costs?

◦ Take off capability. Can the aircraft generate enough thrust and lift to take off in the required distance?

◦ Power requirement. Can we provide an adequate amount of energy with available batteries? What size does the battery have to be?

Initial Risk Identification

Feasibility Analysis

Cost Analysis Material Properties Power needs Thrust Analysis Flight Conditions Preliminary Wing Iteration Take-off and Landing Distance

Overview of Feasibility Analysis

Cost Analysis

Materials Properties

Power Analysis

Thrust is dependent upon the diameter of the propeller, the inlet velocity, and the exit velocity. The exit velocity is impossible to calculate analytically, but we do have an empirical equation developed by a RC enthusiast.

For static thrust:

For dynamic Thrust:

Simplified:

Thrust Analysis

The diameter has the biggest impact on thrust developed. This is confirmed by standard rule of thumb among hobbyists as well as by data published by APC

The APC data is generated by their own CFD analysis and is available for all their propellers

We will mostly be using our empirical equation to get estimates for static thrust, as the dynamic thrust element is considered suspect

We will also use APC data, as well as a simplified model that was found:

These 3 different thrust estimates will give us a good ballpark estimate of what to expect from a particular prop and RPM

Thrust Analysis continued

𝐹=𝑃∗𝐷3∗𝑅𝑃𝑀2∗10−10

The equations and data also require an RPM input. This can be estimated if the Kv rating of the motor is known◦ Kv Rating * Voltage = Ideal RPM

These have been put together into an excel calculator

Depending on our motor, propeller, and current draw, we should be able to get between 10 and 15 pounds of thrust

Testing is needed to refine this

Thrust Analysis continued

Preliminary Flight Conditions

Preliminary Wing Design: Iteration 1

Feasibility: Take-Off and Landing Distance

XFLR5 simulations suggest lower performance than expected. It is known that physical wings generate less lift and more drag than airfoils suggest, but the values are unexpectedly low.

Simulation efforts are proceeding using ANSYS. If this proves to be a reliable method, we will proceed using the simulation process described on the next slide.

Any simulation effort requires some comparison to measured data in order to establish that the simulation is working. We will compare to measured airfoil data by recreating the UIUC windtunnel tests.

Currently we have encountered difficulty meshing the S1223, S1223RTL and S1210 airfoils

Engineering Analysis

Simulation workflow

Desired Performance

Quality or Feature

Simulation

Not Possible

Possible

Refine if needed

Analyze Consequences

of Design

Reconsider desire and

solution

Populate new requirements

After our analysis we have reached the following conclusions:

◦ Providing adequate electrical energy should not be an issue if a properly sized battery is purchased.

◦ The takeoff ability of the aircraft will need to be worked on with further wing development and analysis, and the testing of propulsion systems to determine hard thrust numbers. Thrust will need to be maximized.

◦ Cost will be a significant issue if not addressed. However, we can pursue strategies to reduce cost, including using any available loaned or donated materials. Updated risk intensity shown below.

Risk Review

Thanks to Professor Wellin we have been donated these items:

◦ Hacker A60-5S V2 28 Pole Brushless Motor x1◦ Phoenix edge lite 130 Electronic Speed Controller, x1◦ insulated copper wire (7 gage) ~3feet◦ Mejzlik modellbau 27x12TH Propeller, hollow carbon fibre, x1◦ APC C-2 21x12W Propeller, plastic x1◦ APC C-2 22x10E Propeller, plastic x1◦ APC C-2 24x12 Propeller, plastic x1

Donated Items

Developing test plan for the evaluation of:◦ Propulsion System◦ Structural strength of wing rib◦ Material Property testing of Balsa wood and numerous 3D

printed plastics◦ Looking into wind tunnel availability

Planning

Gantt Chart

At the moment we remain on schedule

Comments Concerns Complaints

Questions?

Simulations of basic wings is successful Simulation of wings of interest is

encountering issues with meshing

Current Simulation Status

Meshing problemsProblematic Region

Continue to address meshing problems Resolve simulation and compare to known

values from windtunnel testing If that is successful we will be able to fill in

gaps in published data using the simulation and verify later.

Bounds of error will be assumed to be similar to error between simulation and comparison data

Short Term Simulation Plan

S1223 Published Data

Selig, M.S., Lyon, C.A., Giguère, P., Ninham, C.N., and Guglielmo, J.J.,Summary of Low-Speed Airfoil Data, Vol. 2, SoarTech Publications, Virginia Beach, VA, 1996

S1223RTL Published Data

Selig, M.S., Lyon, C.A., Giguère, P., Ninham, C.N., and Guglielmo, J.J.,Summary of Low-Speed Airfoil Data, Vol. 2, SoarTech Publications, Virginia Beach, VA, 1996