Performance-Based Preliminary Design and Selection of Aircraft Configurations for Unmanned Cargo Operations

2021 ◽  
pp. 107-131
Author(s):  
Yasim Julian Hasan ◽  
Falk Sachs
Keyword(s):  
Preliminary Design ◽  
Aircraft Configurations ◽  
Selection Of

scholarly journals Aero-Structural Optimization of Joined-Wing Aircraft

2017 ◽  
Vol 2017 (4) ◽  
pp. 48-63
Author(s):  
Miłosz Kalinowski
Keyword(s):  
Structural Optimization ◽  
Search Algorithm ◽  
Optimization Methods ◽  
Global Search ◽  
Preliminary Design ◽  
Electric Aircraft ◽  
Modular Algorithm ◽  
Lifting Surfaces ◽  
Joined Wing ◽  
Aircraft Configurations

Abstract Joined-wing aircraft due to its energy characteristics is a suitable configuration for electric aircraft when designed properly. However, because of the specific for this aircraft phenomenons (e.g. static indeterminacy of structure, aerodynamic interference of lifting surfaces) it demands more complicated methods to model its behavior than a traditional aircraft configurations. For these reasons the aero-structural optimization process is proposed for joined-wing aircrafts that is suitable for preliminary design. The process is a global search, modular algorithm based on automatic geometry generator, FEM solver and aerodynamic panel method. The range of aircraft was assumed as an objective function. The algorithm was successfully tested on UAV aircraft. The improvement of 19% of total aircraft range is achieved in comparison to baseline aircraft. Time of evaluation of this global search algorithm is similar to the time characteristic for local optimization methods. It allows to reduce the time and costs of preliminary design of joined-wing.

Upgrading of the STP Uithoorn: treatment of nutrient rich wastewater from horticulture

2005 ◽  
Vol 52 (4) ◽  
pp. 81-90 ◽  
Author(s):  
P. Piekema ◽  
R. Neef
Keyword(s):  
Primary Treatment ◽  
Preliminary Design ◽  
Operational Control ◽  
Tertiary Treatment ◽  
Wide Range ◽  
High Loading Rate ◽  
Stage System ◽  
Nutrient Discharge ◽  
Selection Of ◽  
System Choice

The STP Uithoorn will be upgraded to accommodate the treatment of wastewater from a growing population and to meet more stringent nutrient discharge limits in 2006. In 2003 a system choice and preliminary design was made for the upgrading. A special feature is the nutrient rich wastewater flow from the rapidly developing horticulture in the area. Since the future loads from horticulture are highly uncertain, flexibility of the STP after upgrading is an important issue. A three stage system was selected: improved physical-chemical primary treatment, secondary treatment by activated sludge, and tertiary treatment by denitrifying filters. In this way an important part of the existing infrastructure can be reused, and flexibility is assured by constructing the tertiary treatment in modules and by providing a wide range of operational control possibilities. In this paper the process of system choice and selection of type of tertiary treatment are described, as well as the optimisation of the existing treatment. In order to determine the feasibility of allowing a high loading rate on the existing secondary clarifiers, a two-dimensional hydraulic model of the clarification process was used.

scholarly journals On the Selection of Optimal Propeller Diameter for a 120m Cargo Vessel

2018 ◽  
Author(s):  
Jennie Andersson ◽  
Robert Gustafsson ◽  
Arash Eslamdoost ◽  
Rickard E. Bensow
Keyword(s):  
Open Water ◽  
Operating Conditions ◽  
Series Data ◽  
Preliminary Design ◽  
Optimum Diameter ◽  
Viscous Losses ◽  
Computational Fluid Dynamics Cfd ◽  
Propulsion Unit ◽  
Hydrodynamic Effects ◽  
Selection Of

In the preliminary design of a propulsion unit the selection of propeller diameter is most commonly based on open water tests of systematic propeller series. The optimum diameter obtained from the propeller series data is however not considered to be representative for the operating conditions behind the ship, instead a slightly smaller diameter is often selected. We have used computational fluid dynamics (CFD) to study a 120m cargo vessel with an integrated rudder bulb-propeller hubcap system and a 4-bladed propeller series, to increase our understanding of the hydrodynamic effects influencing the optimum. The results indicate that a 3-4 % smaller diameter is optimal in behind conditions in relation to open water conditions at the same scale factor. The reason is that smaller, higher loaded propellers perform better together with a rudder system. This requires that the gain in transverse kinetic energy losses thanks to the rudder overcomes the increase in viscous losses in the complete propulsion system.

Characteristics Charts for Preliminary Design and Selection of a Gas Turbine Cogeneration Plant

1995 ◽  
Author(s):  
K. Sarabchi ◽  
G. T. Polley
Keyword(s):  
Performance Analysis ◽  
Gas Turbine ◽  
Performance Prediction ◽  
Integrated System ◽  
Performance Criteria ◽  
Preliminary Design ◽  
Cogeneration Plant ◽  
Work Efficiency ◽  
Boiler Efficiency ◽  
Selection Of

The important and well-established performance criteria for assessment of a gas turbine cogeneration plant (GTCP) were examined. It was found that expressions could be derived for these criteria in terms of two key parameters: work efficiency and boiler efficiency. Three characteristics charts were then constructed. These covered gas turbine analysis, boiler analysis and GTCP performance analysis respectively. It is then demonstrated how these charts may be used as an effective tool for both performance prediction and preliminary design analysis. Thermodynamic design of a GTCP as an integrated system is also investigated and discussed.

Design charts for the selection of acoustical enclosures for diesel engine generator sets

2003 ◽  
Vol 217 (3) ◽  
pp. 329-336 ◽  
Author(s):  
T. A. Osman
Keyword(s):  
Diesel Engine ◽  
Insertion Loss ◽  
Design Stage ◽  
Preliminary Design ◽  
Generating Sets ◽  
Design Charts ◽  
Wide Range ◽  
Preliminary Design Stage ◽  
Generator Sets ◽  
Selection Of

It has been realized that attenuation of the noise radiated from diesel engine generating sets is a challenge for the designer. The enclosure, which may be designed for noise reduction, has to allow for the flow of the necessary amount of air. The present work is an attempt to tackle such a contradictory problem. A mathematical model is developed to predict the enclosure design configuration. The parameters affecting the insertion loss, such as enclosure and silencer dimensions, number of baffles, and sound absorption material specifications are taken into account. To verify the developed model, experimental measurements based on ISO 8528 part 10 are conducted. Four different generating sets covering a wide range of power rating are employed. The effect of changing each parameter on the insertion loss is studied separately for the chosen range. Design charts, based on the results of the present investigation, are constructed to facilitate the section of a proper acoustical enclosure configuration at the preliminary design stage.

The Practical Design of Turbocharger Turbines Using a Throughflow-Based Optimisation Process

2012 ◽  
Author(s):  
Graham D. Cox
Keyword(s):  
Knowledge Base ◽  
Electric Motor ◽  
Internal Combustion Engines ◽  
Preliminary Design ◽  
Combustion Engines ◽  
Two Stage ◽  
General Applicability ◽  
Choice Of Major ◽  
Practical Design ◽  
Selection Of

The modern trends in automotive turbocharger applications are towards the boosting of smaller internal combustion engines and more advanced systems including two-stage, turbo-compounding and hybrid electric-motor assist. Off-the-shelf turbochargers will become a smaller share of the market and the choice of major parameters for the compressor and turbine, e.g. speed and diameter, will fall outside of the manufacturer’s knowledge base. The selection of the compressor and turbine may even be independent. The only certainty is that the turbomachinery will have to be small, cheap and efficient. To provide some guidance to the turbine designer, this paper presents the results of a study in which practical designs have been generated to cover the range of conceivable parameters, presented in non-dimensional terms to provide general applicability. All the designs are generated using a throughflow-based optimisation system in which the candidate geometries are assessed against mechanical as well as aerodynamic and inertia targets. Analysis of the results gives clues to the form of the basic empiricism that would be of use in the preliminary design of automotive turbocharger turbines.

scholarly journals Determining the Aerodynamic Characteristics of a Propeller-Driven Anti-UAV Fighter While Designing Air Propellers

2021 ◽  
Vol 2021 (4) ◽  
pp. 53-67
Author(s):  
Vasyl Loginov ◽  
Yevgen Ukrainets ◽  
Viktor Popov ◽  
Yevgen Spirkin
Keyword(s):  
Wind Tunnel ◽  
Numerical Methods ◽  
High Efficiency ◽  
Aerodynamic Characteristics ◽  
The Body ◽  
Physical Experiments ◽  
Thrust And Torque ◽  
Aircraft Configurations ◽  
Aerodynamic Configuration ◽  
Selection Of

Abstract Given the rising importance of unmanned aerial vehicles (UAVs), this article addresses the urgent scientific problem of determining the aerodynamic characteristics of a UAV while laying out the propellers for the wings. We discuss the methodology for experimental wind-tunnel studies of aircraft configurations with propellers. It is shown that a characteristic feature of the configuration small-elongation wing with propellers is the absence of elements that are not affected by propellers. This feature makes it difficult to implement and automate a wind tunnel experiment, since there are problems with providing similar criteria for a working propeller; it is difficult to achieve perfect balancing for solid drive propellers, which causes vibration, the level of which depends on uncontrolled factors; the inability to neglect the presence of the body elements influence to the blades of propellers; the difficulty of direct measuring propeller thrust and torque. The presented methodology involves the integrated usage of experimental and numerical methods to eliminate the difficulties in conducting physical experiments in a wind tunnel. This approach makes it possible to combine the high credibility of experimental data in the study of the physical essence of phenomena with high efficiency and accuracy in determining aerodynamic characteristics by numerical methods. Using this approach, we established dependences of the aerodynamic characteristics of the small-elongation wing configuration with counter-rotating propellers on the geometric and kinematic parameters of the configuration for other extensions and constrictions of the wings. These data can serve as the basis for the development of recommendations for the selection of sensible geometric parameters of the aerodynamic configuration of a small-elongation wing with counter-rotating propellers.

Preliminary Design of Mooring Systems

1982 ◽  
Vol 26 (01) ◽  
pp. 25-35
Author(s):  
Michael S. Triantafyllou
Keyword(s):  
Dynamic Performance ◽  
Static Solution ◽  
Approximate Expression ◽  
Multiple Time ◽  
Preliminary Design ◽  
Spectral Techniques ◽  
Dynamic Solution ◽  
Parametric Search ◽  
Slow Part ◽  
Selection Of

The preliminary design of mooring systems is formulated by separating the quasi-steady solution from the dynamic solution. A multiple time-scale expansion provides the appropriate equations, which are nonlinear for the quasi-steady part and linear space varying for the dynamic part. The fast dynamic solution consists of a fast varying and a slowly varying part with respect to space. An asymptotic solution is obtained by using the WKB method for the fast part, while an approximate expression is derived for the slow part. The resulting solution is simple and can be used to determine the dynamic behavior of complex systems, while permitting an extensive parametric search and the use of spectral techniques. This formulation leads to rational measures of the dynamic performance which, combined with cost considerations obtained from the static solution, permit an optimal selection of the system parameters. An example demonstrates the features of this methodology.

Preliminary Design of a High Bypass Ratio Turbofan Engine

2009 ◽  
Author(s):  
Syed Muhammad Hassan Rizvi ◽  
Kenneth W. Ramsden ◽  
Vasslios Pachidis
Keyword(s):  
Pressure Ratio ◽  
Preliminary Design ◽  
Compressor Cascade ◽  
Design Study ◽  
Turbofan Engine ◽  
Turbine Engine ◽  
High Pressure Compressor ◽  
The Uk ◽  
Bypass Ratio ◽  
Selection Of

This paper presents a preliminary design of a high bypass ratio turbofan engine which has been developed through a Masters Degree project at Cranfield University in the UK. It is well known that the design process for a new gas turbine engine requires an understanding of the interrelated requirements of aerodynamics, thermodynamics, heat transfer, materials choice and engine control. Accordingly, the designer’s solution is inevitably the result of compromises involving a large number of mostly conflicting parameters. The preliminary design study in this paper relates to assessment of a suitable engine to satisfy the specification needs of a small airliner. The particular aircraft chosen for the design is one designed by a group of master’s degree students in the College of Aeronautics at Cranfield University. The paper includes a description of that aircraft specification for which the cruise phase is chosen as a design point for the engine. The overall objective of the design is to achieve the least (practical) specific fuel consumption so as to maximize aircraft range. The paper presents the results of the iterative design study and includes the effects of turbine entry temperature, bypass ratio, overall pressure ratio and fan pressure ratio. Subsequently, a procedure for the selection of the annulus geometry for each of the turbomachinery components and the combustor is illustrated which can deliver an acceptable gas path for the entire engine. Finally, using well established compressor cascade data, an approximate method is illustrated for the prediction of the performance characteristic of the high pressure compressor of the core engine.

A model for solar powered aircraft preliminary design

2008 ◽  
Vol 112 (1128) ◽  
pp. 57-78 ◽  
Author(s):  
E. Rizzo ◽  
A. Frediani
Keyword(s):  
Mathematical Model ◽  
Great Emphasis ◽  
Preliminary Design ◽  
Research Activities ◽  
Solar Powered ◽  
Flying Wings ◽  
Long Endurance ◽  
Near Future ◽  
Aircraft Configurations ◽  
Aerodynamic Configuration

Abstract Solar powered aircraft are becoming more and more interesting for future long endurance missions at high altitudes, because they could provide Earth monitoring, telecommunications, etc. without any atmospheric pollution and, hopefully in the near future, with competitive costs compared with satellites. The research activities carried out till now have been mainly focused on flying wings or conventional aircraft configurations, with a great emphasis on the technological aspects. The present paper aims to define a mathematical model for solar powered aircraft preliminary design, valid independently of the aerodynamic configuration. A preliminary analysis is carried out in order to simulate Helios and the results are compared with those available from the flights of this aircraft. The proposed mathematical model is used also to compare four different aircraft configurations, namely: a flying wing, a conventional aircraft, a twin boom aircraft and a biplane aircraft. The results obtained are discussed in the paper and an optimum aircraft is analysed.

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