Thesis-Project.docx - 1 Abstract Loitering monition...

1
Abstract
Loitering monition capability is a key element of any IFPA (indirect fire precision attack)
weapon system. To guarantee a precise striking accuracy with less collateral damage as
possible constant flight behaviour must be ensured. This study will investigate the flight
characteristics of a modern missile weapon system and recommendations for aerodynamically
modifications will be given.
Loitering weapons fill the gap in the capabilities needed by the Armed Forces. Throughout the
more complicated spectrums of conflicts the potential of artillery is limited and more
precision in range is needed. In lack of detailed design data a CAD model of the missile must
be designed with adjusting the dimensions to the given performance data and will be critically
analysed with CFD. For the analysis a two dimensional model of different aerofoils will be
use to compare the lift characteristics, lift-drag ratio or pitch characteristics to validate the
most suitable profile. By variegating control surface parameters like sweep angle, AOI,
position or length of wing the influence to the flight behaviour will be obtained and possible
modifications for the three dimensional model will be derived.

2
Table of Contents
Introduction ............................................................................................................................................ 2
Literature Review ................................................................................................................................... 4
The Lift and Drag in Aerodynamics Design of an Aircraft ................................................................. 6
Tactile missile drag estimation ......................................................................................................... 12
The lift and the drag coefficient .................................................................................................... 16
Uses of Computational Fluid Dynamics in Missile Design .............................................................. 17
CFD (Computational Fluid Dynamics) Simulation .......................................................................... 18
Airfoil ............................................................................................................................................... 19
Missile Modelling and Design Objective ......................................................................................... 21
Comparison of Airfoil Design .......................................................................................................... 23
Modeling and Meshing of Symmetric airfoil ................................................................................ 23
Modeling and meshing of Asymmetrical airfoils .......................................................................... 24
Calculation of Aerodynamic lift coefficient .................................................................................. 26
Aerodynamic Characterization of Fire Shadow Loitering Munition through combined internal and
external CFD Simulation .................................................................................................................. 30
Test Details and Configuration ..................................................................................................... 31
Analysis and Numerical simulation .............................................................................................. 32
Results and Discussion ................................................................................................................. 35
Summary ...................................................................................................................................... 42
Numerical 2D simulation of aerodynamic performance for two airfoils ........................................... 42
Comparison of Aerodynamics Characteristics of NACA 4415 and NACA 0015 .............................. 44
Mathematical and Theoretical Background .................................................................................. 45
Physical Setup and Boundary Conditions ..................................................................................... 46
Geometry of NACA 4415 and NACA 0015 ................................................................................. 47
Summary ...................................................................................................................................... 55
Conclusion and Recommendations ...................................................................................................... 56
References ............................................................................................................................................ 59

3
Introduction
Best performance and high efficiency, these expectations were faced to the defence industry.
Historically, reliable results for complex questions in aerospace and aeronautical industries
have been answered by testing prototypes physically. This means in case of the design for
military vehicles were high precision is required very expensive and time-consuming method.
Especially for missiles were every prototype can be used only once. Fortunately, modern
CFD software helps to solve complex problems for quite every imaginable scenario. It´s an
integral part of the industry and an important tool for specialists and engineers guide them
through the design process.