scholarly journals Preliminary Design of a Small Unmanned Battery Powered Tailsitter

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Bo Wang ◽  
Zhongxi Hou ◽  
Zhaowei Liu ◽  
Qingyang Chen ◽  
Xiongfeng Zhu
Keyword(s):  
Energy Consumption ◽  
Design Methodology ◽  
Design Space ◽  
Preliminary Design ◽  
Wing Loading ◽  
Detailed Design ◽  
Discharge Model ◽  
Battery Discharge ◽  
Power And Energy

This paper presents a preliminary design methodology for small unmanned battery powered tailsitters. Subsystem models, including takeoff weight, power and energy consumption models, and battery discharge model, were investigated, respectively. Feasible design space was given by simulation with mission and weight constraints, while the influences of wing loading and battery ratio were analyzed. Case study was carried out according to the design process, and the results were validated by previous designs. The design methodology can be used to determine key parameters and make necessary preparations for detailed design and vehicle realization of small battery powered tailsitters.

Preliminary Design and Performance of Counter Rotating Turbines for Open Rotors: Part II — 0-D Methodology and Case Study for a 160 PAX Aircraft

2016 ◽  
Author(s):  
Pablo Bellocq ◽  
Inaki Garmendia ◽  
Jordane Legrand ◽  
Vishal Sethi
Keyword(s):  
Design Methodology ◽  
Design Space Exploration ◽  
Design Space ◽  
Space Exploration ◽  
Preliminary Design ◽  
Regulatory Constraints ◽  
Trade Offs ◽  
And Performance ◽  
The Impact

Direct Drive Open Rotors (DDORs) have the potential to significantly reduce fuel consumption and emissions relative to conventional turbofans. However, this engine architecture presents many design and operational challenges both at engine and aircraft level. At preliminary design stages, a broad design space exploration is required to identify potential optimum design regions and to understand the main trade offs of this novel engine architecture. These assessments may also aid the development process when compromises need to be performed as a consequence of design, operational or regulatory constraints. Design space exploration assessments are done with 0-D or 1-D models for computational purposes. These simplified 0-D and 1-D models have to capture the impact of the independent variation of the main design and control variables of the engine. Historically, it appears that for preliminary design studies of DDORs, Counter Rotating Turbines (CRTs) have been modelled as conventional turbines and therefore it was not possible to assess the impact of the variation of the number of stages (Nb) of the CRT and rotational speed of the propellers. Additionally, no preliminary design methodology for CRTs was found in the public domain. Part I of this two-part publication proposes a 1-D preliminary design methodology for DDOR CRTs which allows an independent definition of both parts of the CRT. A method for calculating the off-design performance of a known CRT design is also described. In Part II, a 0-D design point efficiency calculation for CRTs is proposed and verified with the 1-D methods. The 1-D and 0-D CRT models were used in an engine control and design space exploration case study of a DDOR with a 4.26m diameter an 10% clipped propeller for a 160 PAX aircraft. For this application: • the design and performance of a 20 stage CRT rotating at 860 rpm (both drums) obtained with the 1-D methods is presented. • differently from geared open rotors, negligible cruise fuel savings can be achieved by an advanced propeller control. • for rotational speeds between 750 and 880 rpm (relatively low speeds for reduced noise), 22 and 20 stages CRTs are required. • engine weight can be kept constant for different design rotational speeds by using the minimum required Nb. • for any target engine weight, TOC and cruise SFC are reduced by reducing the rotational speeds and increasing Nb (also favourable for reducing CRP noise). However additional CRT stages increase engine drag, mechanical complexity and cost.

Preliminary Design and Performance of Counter Rotating Turbines for Open Rotors: Part I — 1-D Methodology

2016 ◽  
Author(s):  
Pablo Bellocq ◽  
Inaki Garmendia ◽  
Jordane Legrand ◽  
Vishal Sethi
Keyword(s):  
Fuel Consumption ◽  
Design Methodology ◽  
Design Space Exploration ◽  
Design Space ◽  
Preliminary Design ◽  
Flow Conditions ◽  
Power Extraction ◽  
And Performance ◽  
The Impact

Direct Drive Open Rotors (DDORs) have the potential to significantly reduce fuel consumption and emissions relative to conventional turbofans. However, this engine architecture presents many design and operational challenges both at engine and aircraft level. At preliminary design stages, a broad design space exploration is required to identify potential optimum design regions and to understand the main trade offs of this novel engine architecture. These assessments may also aid the development process when compromises need to be performed as a consequence of design, operational or regulatory constraints. Design space exploration assessments are done with 0-D or 1-D models for computational purposes. These simplified 0-D and 1-D models have to capture the impact of the independent variation of the main design and control variables of the engine. Historically, it appears that for preliminary design studies of DDORS, Counter Rotating Turbines (CRTs) have been modeled as conventional turbines and therefore it was not possible to assess the impact of the variation of the number of stages (Nb) and rotational speed of the propellers. Additionally, no preliminary design methodology for CRTs was found in the public domain. Part I of this two-part publication proposes a 1-D preliminary design methodology for DDOR CRTs. It allows an independent definition of the Nb, rotational speeds of both parts of the CRT, inlet flow conditions, inlet and outlet annulus geometry as well as power extraction. It includes criteria and procedures to calculate: power extraction in each stage, gas path geometry, blade metal angles, flow conditions at each turbine plane and overall CRT efficiency. The feasible torque ratios of a CRT are discussed in this paper. A form factor for the CRT velocity triangles is defined (similar to stage reaction on conventional turbines) and its impact on performance and blade design is discussed. A method for calculating the off-design performance of a CRT is also described in Part I. In Part II, a 0-D design point (DP) efficiency calculation for CRTs is proposed as well as a case study of a DDOR for a 160 PAX aircraft. In the case study, three main aspects are investigated: A) the design and performance of a 20 stage CRT for the DDOR application; B) the impact of the control of the propellers on cruise specific fuel consumption, C) the impact of the design rotational speeds and Nb of the CRT on its DP efficiency, engine fuel consumption and engine weight.

scholarly journals Optimal Sizing of Electric Multirotor Configurations

2018 ◽  
Vol 233 ◽  
pp. 00028 ◽  
Author(s):  
Giulio Avanzini ◽  
Emanuele L. de Angelis ◽  
Fabrizio Giulietti ◽  
Edmondo Minisci
Keyword(s):  
Evolutionary Algorithm ◽  
Design Space ◽  
Weight Fraction ◽  
Optimal Performance ◽  
Optimal Sizing ◽  
Performance Requirements ◽  
Discharge Model ◽  
And Performance ◽  
Definition Of ◽  
Battery Discharge

A sizing tool for the definition of the configuration of electrically powered multirotor platforms is developed, which accounts for a realistic battery discharge model. The tool is developed to provide the community with the possibility of deriving the best configuration for performing a given task, while accounting for specific constraints and performance requirements. An evolutionary algorithm is used for searching the design space and to identify feasible designs with optimal performance in terms of maximum hovering time on the target and payload weight fraction.

scholarly journals BREED - A Problem Solving Bionic Design Methodology

2020 ◽  
Author(s):  
Rohith Vaidyanathan ◽  
Gururaj Fattepur ◽  
Ravi Guttal
Keyword(s):  
Problem Solving ◽  
Engineering Design ◽  
Design Methodology ◽  
Design Space ◽  
Bionic Design ◽  
Matching Technique ◽  
Bionic Structure ◽  
To Come ◽  
Structural Dome

Bionic designs which have evolved from time-tested strategies of nature have beena source of inspiration for designers to solve problems. The beauty of nature’s formis derived from effective evolution and robustness of its function. Current bionicdesign methods are analogical and hence are discordant to the design engineeringworkflow. In this paper, a methodology is proposed which suggests suitable bionicstructures to a given design space. The methodology consists of the following stageswhich are Bionic representation, Relation, Emulation, Engineering specifications,Design verification and optimisation (BREED) and finally realization. Thismethodology aims to function as a systematic problem-solving approach to retrievestructural inspirations from nature and mimic its form. The methodology alsointegrates biological inputs to the context of an engineering design problem.Inspiration and validation phases of the bionic structure are represented as a V-model. The designer can leverage this framework to come up with novel bionicdesign concepts. A structural dome is used as a case study to demonstrate theprocedure of BREED methodology. Biological forms for the dome are obtainedusing a spectral matching technique. The bionic design is validated after applyingrelevant boundary conditions and by using proven engineering methods.

scholarly journals Turbocharger Axial Turbines for High Transient Response, Part 1: A Preliminary Design Methodology

2019 ◽  
Vol 9 (5) ◽  
pp. 838 ◽  
Author(s):  
Glen Walsh ◽  
Marco Berchiolli ◽  
Gregory Guarda ◽  
Apostolos Pesyridis
Keyword(s):  
Fluid Dynamics ◽  
Design Methodology ◽  
Design Space ◽  
Performance Model ◽  
Preliminary Design ◽  
Flow Conditions ◽  
Design Algorithm ◽  
Static Efficiency ◽  
Steady State Operation ◽  
Axial Turbines

This paper proposes a preliminary design algorithm for application of a turbocharger axial turbine, based on turbine thermodynamic analysis and the Ainley-Mathieson performance model that converges to the optimal design based on a set of input parameters and engine boundary conditions. A design space sweep was conducted, and a preliminary design was generated with a predicted total to static efficiency of 74.94%. CFD (computational fluid dynamics) was used to successfully validate the algorithm and show the preliminary design had a total to static efficiency of 73.98%. The design also produces the required power to support steady-state operation of the compressor in both free flow conditions and with a constrained pressure outlet.

Assessing determinants of sustainable upgrade of existing buildings

2019 ◽  
Vol 18 (1) ◽  
pp. 270-292
Author(s):  
John Dadzie ◽  
Goran Runeson ◽  
Grace Ding
Keyword(s):  
Energy Consumption ◽  
Design Methodology ◽  
Existing Buildings ◽  
Building Stock ◽  
Content Type ◽  
Existing Building ◽  
Sustainable Technologies ◽  
Energy Consumption Patterns ◽  
Main Components

Purpose Estimates show that close to 90% of the buildings we will need in 2050 are already built and occupied. The increase in the existing building stock has affected energy consumption thereby negatively impacting the environment. The purpose of this paper is to assess determinants of sustainable upgrade of existing buildings through the adoption and application of sustainable technologies. The study also ranks sustainable technologies adopted by the professionals who participated in the survey with an in-built case study. Design/methodology/approach As part of the overall methodology, a detailed literature review on the nature and characteristics of sustainable upgrade and the sustainable technologies adopted was undertaken. A survey questionnaire with an in-built case study was designed to examine all the sustainable technologies adopted to improve energy consumption in Australia. The survey was administered to sustainability consultants, architects, quantity surveyors, facility managers and engineers in Australia. Findings The results show a total of 24 technologies which are mostly adopted to improve energy consumption in existing buildings. A factor analysis shows the main components as: lighting and automation, heating, ventilation and air conditioning (HAVC) systems and equipment, envelope, renewable energy and passive technologies. Originality/value The findings bridge the gap in the literature on the adoption and application of sustainable technologies to upgrade existing buildings. The technologies can be adopted to reduce the excessive energy consumption patterns in existing buildings.

scholarly journals A model-based design methodology for flight control systems: Global 7500 pitch control case study

2021 ◽  
pp. 095441002110247
Author(s):  
Jonathan Liscouët
Keyword(s):  
Control Systems ◽  
Flight Control ◽  
High Performance ◽  
Design Methodology ◽  
Aircraft Design ◽  
Preliminary Design ◽  
Design Phase ◽  
Performance Requirements ◽  
Design Challenge

This article introduces an original model-based design methodology addressing a high-performance aircraft design challenge: conflicting performance requirements. The case study of the Global 7500 elevator actuation system also provides in-depth insight into the complex design process of today’s fly-by-wire flight control systems. The methodology presented here redefines the aircraft manufacturer’s involvement in the design process of the systems, implementing analysis and iteration capabilities early in system development. To this end, it introduces a novel modeling approach for analyzing loaded rate requirements by simulating closed-loop performance with a generic nonlinear second-order state filter, including the main performance limitations without requiring a preliminary design definition. In this way, it provides means to mature the system requirements and addresses requirement conflicts upfront. Then, a simulation-based preliminary sizing and performance assessment validates the candidate design concept. It also secures the preliminary design phase by implementing advanced design uncertainties and involving interfacing systems and disciplines early in the process. The redefined methodology identified directly that the problem’s root cause was a conflict between stability and control and flutter protection requirements. It also indicated that the first sizing driver is the response time required under a specific failure case. These findings lead to an optimal elevator actuator design compliant with matured performance requirements. Thus, the methodology resolved a design challenge blocking the Global 7500 aircraft development and prevented redesign occurrences later during the detailed design phase. In this way, it directly contributed to the successful development of the Global 7500 and its optimal operational performance. This methodology applies to future aircraft design challenges, and the technical insight provides valuable lessons learned for high-performance T-tail business jets.

Energy Consumption Pattern of Residential Buildings: Case Study of Residential Area in Batu Pahat, Johor

2020 ◽  
Vol 12 (9) ◽  
Author(s):  
Junaidah Jailani ◽  
◽  
Norsyalifa Mohamad ◽  
Muhammad Amirul Omar ◽  
Hauashdh Ali ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Residential Buildings ◽  
Residential Area ◽  
Consumption Pattern ◽  
Air Conditioners ◽  
Residential Sector ◽  
Waste Energy ◽  
Main Factor ◽  
Energy Consumption Pattern

According to the National Energy Balance report released by the Energy Commission of Malaysia in 2016, the residential sector uses 21.6% of the total energy in Malaysia. Residents waste energy through inefficient energy consumption and a lack of awareness. Building occupants are considered the main factor that influences energy consumption in buildings, and to change energy consumption on an overall scale, it is crucial to change individual behaviour. Therefore, this study focused on analysing the energy consumption pattern and the behaviour of consumers towards energy consumption in their homes in the residential area of Batu Pahat, Johor. A self-administrated questionnaire approach was employed in this study. The findings of this study showed that the excessive use of air conditioners was a significant factor in the increasing electricity bills of homeowners as well as the inefficient use of electrical appliances. Also, this study determined the effect of awareness on consumer behaviour. This study recommends ways to help minimise energy consumption in the residential area.

Contemporary Methods of Designing Rail Vehicle Running Systems with the Use of CAD and CAM Solutions

2020 ◽  
Vol 64 (187) ◽  
pp. 75-80
Author(s):  
Tomasz Antkowiak ◽  
Marcin Kruś
Keyword(s):  
System Design ◽  
Preliminary Design ◽  
Support Design ◽  
Detailed Design ◽  
Final Shape ◽  
Rail Vehicle ◽  
Design Engineers ◽  
Running System ◽  
Cad Cam

The article discusses the process of designing the running system of a rail vehicle using CAD and CAM tools as the solutions supporting the process. It describes the particular stages of design taking its final shape: from a preliminary design, through a detailed design, ending with the stage of production. Each stage includes a presentation of how CAD and CAM tools are used to support design engineers in their practice. Keywords: running system, design, CAD, CAM

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