Radek Vlach

Design of a Pressure Sensor Based on Optical Fiber Bragg Grating Lateral Deformation

This paper describes steps involved in the design and realization of a new type of pressure sensor based on the optical fiber Bragg grating. A traditional pressure sensor has very limited usage in heavy industrial environments, particularly in explosive or electromagnetically noisy environments. Utilization of optics in these environments eliminates all surrounding influences. An initial motivation for our development was the research, experimental validation, and realization of a complex smart pressure sensor based on the optical principle. The main benefit of this solution consists of increasing sensitivity, resistance to electromagnetic interference, dimensions, and potential increased accuracy.

Modeling, simulation and experimental testing of the MEMS thermoelectric generators in wide range of operational conditions

The aim of this paper is to examine the performances of thermoelectric generator based on microelectromechanical systems technology (MEMS) in wide range of operational conditions. The goal is to evaluate capability of this technology for a development of an independent energy source for aircraft applications. Complex overview of MEMS TEG properties obtained by computational modeling, simulations and experimental testing is utilized to define critical phenomena of MEMS TEG technology.

Modeling of Thermal Phenomena in Liquid Cooling System for Aircraft Electric Unit

The aim of this paper is to show the complex thermal analyses used for examining cooling properties of a liquid cooling system integrated into an aircraft fuel metering pump. The cooling is provided by flow of aviation fuel-kerosene. The main advantage of this solution is easy implementation in the place of engine bay. Two methods of thermal analyses are used according to the level of cooling system development. Thermal network analysis is intended for first estimation of thermal conditions and cooling system properties. Numerical thermal analysis based on the finite-element method is used for examination of limit operating conditions which cannot be realized during laboratory testing. The experimental measurement by an infrared camera is used for result verification and identification of thermal properties in laboratory conditions. The goal is to maintain the temperature conditions of the control electronics within the temperature limits.

Control of Stator Winding Slot Cooling by Water Using Prediction of Heating

This project is concerned with non-convectional direct stator winding slot cooling using water. The aim is to find optimal algorithm for control of water cooling. The control algorithms are tested on the experimental device, which is part of real synchronous machine with permanent magnets. The thermal model was built as a base for pump control algorithm model of a machine without thermal sensors. The Thermal model is possible used as predictor of machine heating in real time. This type of water cooling shows better effect on the machine heating than common water cooling system on the cover.

Thermal Modelling of Powerful Traction Battery Charger

In this paper, the author presents survey of the modern approaches in the thermal analysis of power electronic systems. The improvement and the new methods are applied to the real engineering problem. The thermal analysis based on lumped parameters thermal network (LPTN) and finite elements method (FEM) is considered in this paper. The both methods were compared in order to highlight the advantages and defects of each. In addition, an overview of the problems linked to the thermal parameter determination and computation is proposed and discussed.

Predictor for Control of Stator Winding Water Cooling of Synchronous Machine

This project is concerned with non-convectional direct stator winding slot cooling using water. The aim is to find optimal algorithm for control of water cooling. The control algorithms are tested on the experimental device, which is part of real synchronous machine with permanent magnets. The thermal model was built as a base for pump control algorithm model of a machine without thermal sensors. The Thermal model is possible used as predictor of machine heating in real time.

Design of high-speed induction machine for the 6 kW, 120 000 rpm helium turbo-circulator

High-speed ranging requires various equipment, for example compressors, turbo-compressors and turbo-circulators nowadays. Solutions using electrical drive with gearboxes is limited by technical feasibility, lifetime and maintenance of gearbox systems. Thanks to development of frequency converters is possible to build direct high-speed electrical drive. This paper is dealing with design of high-speed solid rotor cage induction machine for running 6 kW, 120 000 rpm helium turbo-circulator. Design of high speed electrical machine for TC is described from requirement specification to manufacturing. Results of mechanical, electromagnetic and thermal calculations are given. Proposed design approached can be used in various application in which high speed electrical machine is required.

Simulation modelling of MEMS thermoelectric generator for aircraft applications

This paper deals with a simulation modelling of a thermoelectric energy harvester for aircraft applications. The aim of this paper is to provide overview of simulation modelling methods, which are used in development process of the autonomic thermoelectric energy harvester. The assumed harvester is based on MEMS technology and is capable to operate as an independent energy source under high range of operational condition required by aircraft applications.

Novel approach to thermoelectric generator modeling as energy harvesting system

This paper describes a novel approach to thermoelectric generator modeling as complex energy harvesting system. The thermoelectric generator model includes three main effects that are Thomson effect, Seebeck effect and Joule heat. The influence of heat sources and heat sinks as well as the load resistance that significantly affect properties of thermoelectric generator is also considered. The SimScape tool that extends Matlab/Simulink is used as tool for physical modeling of thermoelectric generator. Therefore, the energy harvesting model using thermoelectric generator can be easy extended by other device for example DC/DC converter. The energy harvesting model that uses thermoelectric generator (TEG) for the conversion of thermal to electric energy and DC/DC converter is presented in this paper.

Study of the response of the shaft loaded by unbalanced magnetic pull

This paper deals with the analysis of shaft loaded by magnetic force. The shaft deflection and critical speed are obtained by two methods: Transfer Matrix Method and Finite Element Method. The Finite Element Method is well known, however, the Transfer matrix method not. Therefore, the first section of this paper is focused on the brief introduction to this method. The results obtained by both methods are shown and compared. In addition, the study of the magnetic pull modelling strategy impact on the results is performed.