The first THz imaging spectrometer based on continuous-wave radiation is presented. new setup less expensive and more compact than conventional time-domain systems that comprise femtosecond lasers instead. As an example we investigate a human liver with metastasis.

Abstract The operating range of heavy duty gas turbines that feature lean premixed combustion to achieve low NO* emissions is limited by thermoacoustic oscillations. To extend the operational envelope turbine, passive means have be developed suppress instabilities. In order develop complex interaction between acoustics and thermal heat release has taken into account. A new stability chart applicable qualification industrial design been accounts for acoustic properties system including its...

We present a THz investigation of histo-pathological samples including the larynx pig and human liver with metastasis. Our measurements show that different types tissue can be clearly distinguished in transmission images, either within single image or by comparison images obtained for frequency windows. This leads to problem frequencies inherently have spatial resolution. An from two such simple mathematical operation may contain artefacts. discuss measures deal this problem. Furthermore, we...

We have observed four-wave mixing in a semiconductor laser configured to emit on two wavelengths simultaneously. The sidebands exist up 4 THz stemming from modulation of the carrier plasma at difference frequency modes. In addition, we were able generate and detect tunable radiation this device itself suggesting scheme for source.

Two-color semiconductor external cavity laser concepts for terahertz (THz) generation are discussed. By defining three critical characteristics, various two-color configurations experimentally classified with respect to the application of THz generation. According our experimental results, we suggest a new configuration. It is based on an etalon.

Direct emission of terahertz (THz) radiation out a two-colour semiconductor laser is reported and analysed. The geometry the tunable described together with physical mechanisms responsible for at THz difference frequency two pump colours used. On basis this analysis, different possibilities are suggested to increase emitted intensity towards application relevant levels.

Abstract We discuss and analyze concepts for the generation of tuneable continuous wave terahertz (THz) radiation with two color diode lasers. First, different geometries lasers are reviewed. show that THz power in combination external photomixers becomes sufficient scanning imaging applications when optical amplification a tapered amplifier is implemented. Then, concept direct emission out two‐color semiconductor laser reviewed potential this respect to bandwidth achievable critically analyzed.

Environmental compatibility requires low emission burners for gas turbine power plants. In the past, significant progress has been made developing NOx and CO by introducing lean premixed techniques in combination with annular combustion chambers. Unfortunately, these often have a more pronounced tendency to produce combustion-driven oscillations than conventional burner designs. The may be excited such an extent that risk of engine failure occurs. For this reason, prediction thermoacoustic...

Inductors realized with high permeable MnZn ferrite require, unlike iron-powder cores an inherent dis-tributed gap, a discrete air gap in the magnetic circuit to prevent saturation of core material and/or tune inductance value. This large can be divided into several partial gaps order reduce stray field and consequently proximity losses winding. The multi-gap core, by stacking thin plates inserting non-magnetic spacer between plates, however, exhibits substan-tial increase which cannot...

Self-induced combustion driven oscillations are a crucial challenge in the design of advanced gas turbine combustors. Lean premixed combustion, typically used modern turbines, has pronounced tendency to produce these instabilities. Thus, prediction thermoacoustic instabilities phase an engine becomes more and important. A method based on linear acoustic four-pole elements predict ring combustor Siemens 3A-series turbines will be presented this paper. The complex network includes entire...

Abstract Automotive interior lighting has to follow general trends in and will therefore evolve toward hundreds even thousands of RGB LEDs per car. Creating mood at day night, pixelated sign‐like information, theater‐like effects like welcome goodbye messages are examples for outstanding user experience. Furthermore, safety features such as warnings driving state a must autonomous cars. It requires new concepts the whole system reach premium quality data rate (beyond today's bus standard...

In the gas turbine industry, lean premixed combustion is a state-of-the-art technology for reduction of NOx emissions. Due to ever increasing reaction densities and inlet temperatures in modern turbines, combustors reveal an increased tendency form dynamic instabilities. This paper reports on use passive active methods suppression oscillations heavy-duty turbines featuring combustion: Modifications burner exit nozzle are implemented order avoid fluiddynamic feedback change acoustic behavior...

Since the flame of high intense low NOx gas turbine combustion systems is stabilized by swirl, analysis swirl flow very crucial to design and optimization such systems. Although a huge amount publications have been provided on this field just few used Large Eddy Simulation due limits in computer resources. Using large vortical structure resolved leading much better insight features. Hence, paper has applied investigate non reacting confined swirling downstream burner. A accuracy prediction...

The goal of this article is to identify weaknesses the security layer in DLMS/COSEM according Green Book Version 8. In latest versions 7.3 and 8 Book, different layers were added protect sensitive personal data. Security requirements countries with a high level data protection necessitated step. Therefore, intends ensure confidentiality, availability integrity using state-of-the-art methods cryptography. This paper identifies describes vulnerabilities suggests effective countermeasures.

This paper proposes a remarkably efficient modeling method of stray magnetic couplings in an Electromagnetic Compatibility (EMC) filter that focuses on the dominant field power electronic device. The proposed was applied for simulating performance EMC Silicon Carbide (SiC) solar inverter, and its effectiveness verified through comparison measurement simulation results. With method, influence can be predicted well. Further, results matched those with conventional method. Accordingly, number...

The operating range of heavy duty gas turbines featuring lean premix combustion to achieve low Nox emissions may be limited by thermoacoustic oscillations. most promising way extend the operational envelope turbine is modify burner outlet conditions which itself strongly affect flame response on acoustic perturbations. objective present paper analysis and prediction premixed swirl flames are typical for combustion. has been determined experimentally measuring velocity fluctuations a forced...

The accessible bandwidth for tunable terahertz (THz) emission directly out of a diode laser is analysed in terms gain and semiconductor nonlinearities.

To get a better understanding of the formation thermoacoustic oscillations in an annular gas turbine combustor, analysis acoustic eigenmodes has been conducted using finite element method. The influence different boundary conditions and space-dependent velocity sound investigated. actually define eigenfrequency spectrum. Hence, it is crucial to know, e.g., burner impedance. In case combustion system without significant mixing air addition considered this paper, space-dependence minor...

The Vx4.3A gas turbine family has already been well received by the market. Nevertheless market drives technology towards both increased inlet temperatures and reduced emissions. HR3 burner was originally developed for V4.2 Vx4.3 fleet featuring silo combustors in order to mitigate risk of flashback improve NOx- emissions (Prade, Streb, 1996). Due its favourable performance characteristics advanced adapted series with annular combustor. paper reports upon design, testing field evaluation...

This paper proposes a remarkably efficient modeling method of stray magnetic couplings in an Electromagnetic Compatibility (EMC) filter focusing on dominant field power electronic device. The proposed is applied to performance simulation EMC for Silicon Carbide (SiC) solar inverter and its effectiveness verified by comparing measurement result result. By using the method, influence can be well predicted matched with conventional method. Accordingly, number required accurate prediction...

From the very first beginning of V64.3A development HR3 burner was selected as standard design for this frame. The originally developed Vx4.2 and Vx4.3 fleet featuring silo combustors in order to mitigate risk flashback improve NOx-emissions (Prade, Streb, 1996). Due its favourable performance characteristics family advanced adapted Vx4.3A series with annular combustor (hybrid ring – HBR). This paper reports about gas turbines reach NOx emissions below 25 ppmvd CO 10 ppmvd. It is described...