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.
Precision-guided munitions form the core area of all modern armed forces. Due to evolving a
stricter interpretation of the Laws of Armed Conflict and a commonly more litigious
environment especially in stabilisation conflicts there is a bigger operational need to reduce
collateral damage[1]. With greater precision of the warheads size can be reduced, that lowers
costs which is necessary due to the reducing budgets over the last decades[2]. During history
of tactical warfare missiles were continuously improved and adapted to the requirements of
the war theatre. Nowadays, cruise missiles combine two major priorities: protecting military
personnel and destroying the target while avoiding harm to nearby people or structures. They
were developed with the aim to provide the army a relatively inexpensive weapon that can
execute strokes with high precision over long distances [3],[4]. The designation loitering
monition stands for the capability to circle over the target area after its launch, before it´s
assigned to destroy a target from a nearly vertical angle of attack (total endurance ~ 6 hours).
This revolutionary concept differs to ballistic missiles, because is sustains flight through
aerodynamic lift supported by foldable wings and permanent propulsion [5]. Highly
sophisticated loitering munitions missiles are an inexpensive alternative to drones and can
, 4
fulfil a high variety of operation tasks while the operator guides it from save distance. The
modern computation fluid dynamic have solved the complex and numerous problems in
missile and aircraft design.
Numerous works has been done on studying the flight characteristics and design of cruise
missiles and aircrafts. The modern loitering munitions systems with their adjustable wings
now combine these areas and further investigations are necessary. The objectives of the study
are as follows:
1. To research and discuss the requirements for a loitering munitions missile which
sustains flight through aerodynamic lift supported by foldable wings and permanent
propulsion.
2. To emulate a CAD model of a missile according to general conditions and
analytically analyze the lift characteristics, lift-drag ratio or pitch characteristics to
validate the
most suitable profile for this purpose of application.
3. To obtain characteristic data for the flight behavior of a LMM based on
computational fluid dynamics (CFD) modeling and reveal problem areas for
performance
disturbances like the longitudinal static stability.
4. To investigate modification possibilities for increasing the accuracy by
variegating control surface parameters like sweep angle, AOI, position or length
of wing and discuss the effectiveness of the new approach.
The acquired results aim to furthering the knowledge and understanding the flight
characteristics of modern loitering munitions missiles and recommendations for increasing the
effectiveness will be given.
Literature Review
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.
Precision-guided munitions form the core area of all modern armed forces. Due to evolving a
stricter interpretation of the Laws of Armed Conflict and a commonly more litigious
environment especially in stabilisation conflicts there is a bigger operational need to reduce
collateral damage[1]. With greater precision of the warheads size can be reduced, that lowers
costs which is necessary due to the reducing budgets over the last decades[2]. During history
of tactical warfare missiles were continuously improved and adapted to the requirements of
the war theatre. Nowadays, cruise missiles combine two major priorities: protecting military
personnel and destroying the target while avoiding harm to nearby people or structures. They
were developed with the aim to provide the army a relatively inexpensive weapon that can
execute strokes with high precision over long distances [3],[4]. The designation loitering
monition stands for the capability to circle over the target area after its launch, before it´s
assigned to destroy a target from a nearly vertical angle of attack (total endurance ~ 6 hours).
This revolutionary concept differs to ballistic missiles, because is sustains flight through
aerodynamic lift supported by foldable wings and permanent propulsion [5]. Highly
sophisticated loitering munitions missiles are an inexpensive alternative to drones and can
, 4
fulfil a high variety of operation tasks while the operator guides it from save distance. The
modern computation fluid dynamic have solved the complex and numerous problems in
missile and aircraft design.
Numerous works has been done on studying the flight characteristics and design of cruise
missiles and aircrafts. The modern loitering munitions systems with their adjustable wings
now combine these areas and further investigations are necessary. The objectives of the study
are as follows:
1. To research and discuss the requirements for a loitering munitions missile which
sustains flight through aerodynamic lift supported by foldable wings and permanent
propulsion.
2. To emulate a CAD model of a missile according to general conditions and
analytically analyze the lift characteristics, lift-drag ratio or pitch characteristics to
validate the
most suitable profile for this purpose of application.
3. To obtain characteristic data for the flight behavior of a LMM based on
computational fluid dynamics (CFD) modeling and reveal problem areas for
performance
disturbances like the longitudinal static stability.
4. To investigate modification possibilities for increasing the accuracy by
variegating control surface parameters like sweep angle, AOI, position or length
of wing and discuss the effectiveness of the new approach.
The acquired results aim to furthering the knowledge and understanding the flight
characteristics of modern loitering munitions missiles and recommendations for increasing the
effectiveness will be given.
Literature Review
