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Rotorcraft in the Performance Based Navigation International Civil Aviation Organization Implementation

Abstract

European Commision adopted in July new regulations about laying down airspace usage requirements and operating procedures concerning performance based navigation. It is next step in realization of the the global program PBN ICAO. At the 36th General Assembly of ICAO held in 2007, the Republic of Poland agreed to ICAO resolution A36-23 which urges all States to implement PBN. In future aviation concepts the use of Performance Based Navigation (PBN) is considered to be a major Air Traffic Management (ATM) concept element. ICAO has drafted standards and implementation guidance for PBN in the ICAO Doc 9613 “PBN Manual”. The Based Performance Navigation Concept represents and shift from sensor-based to performance based navigation connected with criteria for navigation: accuracy, integrity, availability, continuity and functionality depending on the phase of the flight. Through PBN and changes in the communication, surveillance and ATM domain, many advanced navigation applications are possible to improve airspace efficiency, improve airport sustainability, reduce the environmental impact of air transport in terms of noise and emission, increase safety and improve flight efficiency.

Open access
Development and Testing of Data Reduction Software for Measurements Using Pressure Sensitive Paints

Abstract

The paper concentrates on post-processing of data necessary for pressure measurements using Pressure Sensitive Paints (PSP). The purpose of the study was to develop and test procedures for extraction of the surface pressure distribution from the images captured during PSP tests. The core issues addressed were reduction of the influence of model movement and deformation during wind tunnel run and synchronization between conventional pressure tap measurements and PSP data, necessary for in-situ calibration. In the course of the studies, two approaches on image registration were proposed: the first based on geometric transformation of control points pairs with cross-correlation tuning and the second based on similarity finding and estimation of geometric transformation of the images. Performance of the developed algorithm was tested with use of experimental set-up allowing for controlled movement of the imagined target with micrometer resolution. Both of the proposed approaches to PSP image resection proved to perform well. After testing of the software, the PSP system was used for determination of the pressure field on flat plate exposed to impinging jet. The presented procedures and results can be useful for research groups developing in-house PSP measurements systems for wind tunnel tests and internal flow investigations.

Open access
Electricity Storage in Energy Clusters

Abstract

The article aims to present the results of analysis and evaluation of using energy clusters as a bulk electricity storage. There were developed an analytical model of a sample microgrid (on-grid) and analysed using a software dedicated for optimizing such microgrids. The model of microgrid consist on electricity commercial and residential loads, photovoltaic and wind installations and batteries.

Open access
Green Propulsion Research at TNO the Netherlands

Abstract

This paper describes the recent theoretical and experimental research by the Netherlands Organisation for Applied Scientific Research (TNO) into green replacements for hydrazine, hydrazine derivatives and nitrogen tetroxide, as propellants for in-space propulsion. The goal of the study was to identify propellants that are capable of outperforming the current propellants for space propulsion and are significantly less hazardous for humans and the environment. Two types of propellants were investigated, being monopropellants and bipropellants. The first section of the paper discusses the propellant selection. Nitromethane was found to be the most promising monopropellant. As bipropellant, a combination of hydrogen peroxide (HP) and ethanol was selected, where the ethanol is rendered hypergolic with hydrogen peroxide. The second part of the paper describes the experimental verification of these propellants by means of engine testing. Initiation of the decomposition of nitromethane was found to be problematic, hypergolic ignition of the hydrogen peroxide and ethanol bipropellant however was successfully demonstrated.

Open access
Heat Transfer Determined by the Temperature Sensitive Paint Method

Abstract

The paper presents practical aspects of determining the amount of heat flow by measuring the distribution of surface temperature using the Temperature Sensitive Paint (TSP) method. The quantity measured directly with TSP is the intensity of the excited radiation, which is then converted to surface temperature. The article briefly presents three different methods for determining the heat transfer coefficient. Each of these methods is based on a separate set of assumptions and significantly influences the construction of the measuring station. The advantages of each of the presented methods are their individual properties, allowing to improve accuracy, reduce the cost of testing or the possibility of using them in tests of highly complex objects. For each method a mathematical model used to calculate the heat transfer coefficient is presented. For the steady state heat transfer test method that uses a heater of constant and known thermal power, examples of the results of our own research are presented, together with a comparison of the results with available data and a discussion of the accuracy of the results obtained.

Open access
Increasingly Safe, High-Energy Propulsion System for Nano-Satellites

Summary

Numerous attempts have been undertaken to develop propulsion systems for nano-satellite-type spacecrafts to enable their maneuvering in orbits. One of the potentially viable chemical propellant propulsion systems is a hybrid system. The present paper studies propellant composition variants with the metal hydride as fuel that can be chosen for a nano-satellite hybrid propulsion system. It defines key requirements for chemical propellant nano-satellite propulsion systems, and specifies potential propellant pairs based on a compact metal hydride. The study describes basic technical characteristics of a 1U CubeSat propulsion system.

Open access
Propulsion System Modelling for Multi-Satellite Missions Performed by Nanosatellites

Abstract

Progress in miniaturization of satellite components allows complex missions to be performed by small spacecraft. Growing interest in the small satellite sector has led to development of standards such as CubeSat, contributing to lower costs of satellite development and increasing their service competitiveness. Small satellites are seen now as a prospective replacement for conventional sized satellites in the future, providing also services for demanding users. New paradigms of multi-satellite missions such as fractionation and federalization also open up new prospects for applications of small platforms.

To perform a comprehensive simulation and analysis of future nanosatellite missions, an adequate propulsion system model must be used. Such model should account for propulsion solutions which can be implemented on nanosatellites and used in multi-satellite missions.

In the paper, concepts of distributed satellite systems (constellations, formations, fractionated and federated) are described with a survey of past, on-going and planned multi-satellite nanosatellites missions. Currently developed propulsion systems are discussed and the models of propulsion systems embedded in the WUT satellite simulation model are presented.

Open access
The Accuracy and the Printing Resolution Comparison of Different 3D Printing Technologies

Abstract

The article presents a research conducted with the project: ‘Additive technology used in conduction with optical methods for rapid prototyping of 3D printed models’ [13]. In this article selected three different 3D printing technologies: Fused Deposition Modeling (FDM), Selective Laser Sintering (SLS) and Material Jetting (MJ). Each of them was tested paying special attention to accuracy and resolution of printed elements. Accuracy tests were conducted on the reference specimens which also showed material texture. These specimens were scanned to verified dimensional deviations of printing methods. Printing resolution was verified on a heat exchanger model which was characterized by complicated structure. The highest accuracy and printing resolution was noticed in the MJ technology, PolyJet method on the Objet Eden 260 VS printing machine and the SUP 707 water soluble support material.

Open access
Bionics in Aviation

Abstract

In the paper bionics as a field of knowledge and inspiration in the aviation technologies is presented. Bionics is a branch of science on the borderline of art and biology that studies the way living organisms work, as well as their structure, in order to use the results to build technical devices. In the introduction part definition of bionics is described. In the next part of this document the aviation technologies inspired by nature is depicted. Then, technologies inspired by the butterfly wing are presented. The paper ends with conclusions.

Open access