Publications related to Turbojet

Indication of 310-Helix Structure in Gas-Phase Neutral Pentaalanine

We investigate the gas-phase structure of the neutral pentaalanine peptide. The IR spectrum in the 340-1820 cm-1 frequency range is obtained by employing supersonic jet cooling, infrared multiphoton dissociation, and vacuum-ultraviolet action spectroscopy. ...

AMER CHEMICAL SOC2023

System and method for a microfluidic jet generation from a compact device

Christophe Moser, Jan Krizek

The invention discloses systems and methods for generation of microfluidic jets providing a tool for very precise and localized delivery of e.g., medicaments. The proposed solution overcomes shortcomings related to miniaturization of a jet injection techno ...

2021

Impact of large tip clearance ratios on the performance of a centrifugal compressor

Jürg Alexander Schiffmann, Markus Diehl

Ultra-compact and fast spinning turbomachinery is a key technology to increase performance of domestic heating applications and to address decentralization of power and heat as a consequence of the rise of renewable energy sources. Recently, a heat pump us ...

2019

Mitigation of tip leakage induced phenomena in a low Reynolds number centrifugal compressor via blade loading distribution

Markus Diehl

Reduced-scale refrigeration compressors supported on gas-lubricated bearings have been identified as a key technology for domestic heat pump applications, in order to improve both the system efficiency and the reliability. Unfortunately, reduced-scale mach ...

EPFL2019

Data-Driven Pre-Design Tool for Small Scale Centrifugal Compressors in Refrigeration

Jürg Alexander Schiffmann, Cyril Picard, Violette Mounier

Domestic scale heat pumps and air conditioners are mainly driven by volumetric compressors. Yet the use of reduced scale centrifugal compressors is reconsidered due to their high efficiency and power density. Recent work has demonstrated the technical feas ...

2018

Data-Driven Predesign Tool for Small-Scale Centrifugal Compressor in Refrigeration

Jürg Alexander Schiffmann, Cyril Picard, Violette Mounier

Domestic scale heat pumps and air conditioners are mainly driven by volumetric com-pressors. Yet the use of reduced scale centrifugal compressors is reconsidered due to their high efficiency and power density. The design procedure of centrifugal compressor ...

2018

Turbocompressors for Domestic Heat Pumps – A Critical Review

Jürg Alexander Schiffmann, Jean-Baptiste Carré

Small-scale, oil-free radial compressors on gas lubricated bearings represent a promising alternative to state-of-the-art compressor technology for driving domestic sized heat pumps. The inherent characteristics of turbocompressors manage to fit the heat p ...

2017

A Continuation Multi Level Monte Carlo (C-MLMC) method for uncertainty quantification in compressible inviscid aerodynamics

Fabio Nobile, Pénélope Leyland, Michele Pisaroni

In this work we apply the Continuation Multi-Level Monte Carlo (C-MLMC) algorithm proposed in Collier et al. (2014) to efficiently propagate operating and geometric uncertainties in inviscid compressible aerodynamics numerical simulations. The key idea of ...

Elsevier2017

Dynamic response of an embedded block impacted by aerated high-velocity jets

Anton Schleiss, Rafael Xavier Meriade Duarte

Uplift of blocks from the rock mass at the bottom of plunge pools is the main process of the scouring phenomenon caused by high-velocity jet impact. Although the influence of water and rock on dynamic block ejection has been investigated, no systematic res ...

Taylor & Francis Ltd2016

Optimization of a Shared Tailrace Channel of Two Pumped-Storage Plants by Physical and Numerical Modeling

Giovanni De Cesare, Martin Peter Bieri, Stéphane Christian Olivier Terrier, Sylvain Candolfi

Pump and turbine operations lead to head losses in the tailrace channel. Pumping discharge may be limited due to potential air entrainment into the pump shaft when the downstream reservoir is at its lowest level and the head losses are too high. Regarding ...

2014

Experimental and numerical investigation of narrow impingement cooling channels

Peter Ott, Alexandros Terzis, Bernhard Weigand

Impingement cooling effectiveness of gas turbine vanes and blades can be further increased due to the manufacturing feasibility of integrally cast airfoils which can provide narrow impingement cooling cavities. This study examines experimentally using the ...

Elsevier2013

Control of axisymmetric vortex breakdown in a constricted pipe: Nonlinear steady states and weakly nonlinear asymptotic expansions

François Gallaire, Philippe Meliga

The present paper investigates numerically and theoretically the axisymmetric vortex breakdown occurring in a constricted pipe of infinite extension, i.e., the transition from a smooth columnar state to a breakdown state exhibiting a recirculation bubble. ...

2011

Investigation of High Pressure Turbine End-Wall Film Cooling Performances under Realistic Inlet Conditions

Peter Ott, Magnus Jonsson

The mean value of turbine entry temperature increased to improve efficiency and specific power. Due to the combustor characteristics, thermal and aero-dynamics non-uniformities can be individuated at the turbine inlet section. Then, a further increase in t ...

2011

The influence of pool geometry and induced flow patterns in rock scour by high-velocity plunging jets

Pedro Filipe De Almeida Manso

The dissipation of energy of flood discharges from water releasing structures of dams is often done by plunging jets diffusing in water and impacting on the riverbed downstream. The construction of expensive concrete structures for energy dissipation can b ...

EPFL2006