Publication

Unsteady Flow Numerical Simulations on Internal Energy Dissipation for a Low-Head Centrifugal Pump at Part-Load Operating Conditions

Publications associées (28)

Hydrodynamic dead zone in multiphase geophysical flows impacting a rigid obstacle

When a gravity-driven solid-fluid mixture, such as those in geophysical flows, hits a wall-like rigid obstacle, a metastable jammed zone called hydrodynamic dead zone (HDZ) may emerge. The unjammed-jammed transition of HDZ, controlled by the intricate inte ...

2021

Theory-based scaling laws of near and far scrape-off layer widths in single-null L-mode discharges

Holger Reimerdes, Jan Horacek, Paolo Ricci, Cedric Kar-Wai Tsui, Maurizio Giacomin, Adriano Stagni

Theory-based scaling laws of the near and far scrape-off layer (SOL) widths are analytically derived for L-mode diverted tokamak discharges by using a two-fluid model. The near SOL pressure and density decay lengths are obtained by leveraging a balance amo ...

IOP Publishing Ltd2021

Impact of the Ventilated Cavity on the Thermal Performance of Traditional Wall Structures

Mohammad Rahiminejad, Dolaana Khovalyg

The amount of heat flux passing through the building envelope directly affects the energy use for the thermal conditioning of the building. The ventilated cavity behind the traditional external claddings (e.g., vinyl siding, brick veneer) adjacent to the w ...

AMER SOC HEATING, REFRIGERATING AND AIR-CONDITIONING ENGS2021

Investigation of the Time Resolution Set Up Used to Compute the Full Load Vortex Rope in a Francis Turbine

François Avellan, Andres Müller, Cécile Münch-Alligné, Arthur Tristan Favrel

The flow in a Francis turbine at full load is characterised by the development of an axial vortex rope in the draft tube. The vortex rope often promotes cavitation if the turbine is operated at a sufficiently low Thoma number. Furthermore, the vortex rope ...

2021

Thermal resistance of ventilated air-spaces behind external claddings; definitions and challenges (ASHRAE 1759-RP)

Mohammad Rahiminejad, Dolaana Khovalyg

The presence of an air-space within a building envelope is known to have a varying contribution to the overall thermal performance of the wall assembly due to the combined effect of convection and radiation in the air cavity. In particular, the thermal res ...

2021

Numerical investigation on the volute cutwater for pumps running in turbine mode

Elena Vagnoni, Alessandro Morabito

The hydropower sector has recently raised the interest in pump as turbine (PaT) that can be a valid trade-off between capital cost and performance in micro-scale installations. Nevertheless, the modest efficiency of PaTs often restricts their exploitation. ...

Pergamon-Elsevier Science Ltd2021

District heating and cooling systems to integrate renewable energy in urban areas

Francesca Belfiore

The building sector plays a crucial role in the ongoing energy transition due to its significant share of global energy consumption and carbon dioxide emissions, especially when combined with the estimation that 70% of the world's population will be living ...

EPFL2021

Scale limitations of gas bearing supported turbocompressors for vapor compression cycles

Jürg Alexander Schiffmann

An analysis of single-stage centrifugal compressors supported on dynamic, gas lubricated bearings for driving vapor compression cycles suggests that the maximum feasible compressor power is limited, primarily by the bearing load capacity, in the range from ...

2020