Ricerc@Sapienza

We use DNS to analyze the cooling of a heated curved surface due to a cold subsonic impinging jet. The configuration resembles several industrial applications such as impingement cooling in gas turbine blade. The ratio between the distance from the nozzle (H) and the jet diameter (D) is equal to 5. The results in terms of velocity, turbulence and heat transfer are compared with a reference simulation with where a subsonic jet impingesing on a flat surface. The results allowed to assess the influence of the curvature on the velocity and Nusselt number distribution is assessed.

In the frame of the EUROfusion roadmap for the development of the DEMO power plant, a research activity was carried out to develop a Lithium–Lead/water heat exchanger. The component should be capable to remove nuclear heat deposited in the liquid metal of the Dual Coolant Lithium Lead breeding blanket and feeding a steam turbine, ensuring an efficient thermal power conversion to electricity. One of the selected configurations is the steam generator bayonet tube.

Buoyancy-driven convention from a pair of horizontal heated cylinders, set side by side
inside a square cooled cavity filled with water, is studied numerically. The system of the
conservation equations of mass, momentum and energy expressed in dimensionless form is
solved through a control-volume formulation of the finite-difference method. The pressurevelocity
coupling is handled using the SIMPLE-C algorithm. Numerical simulations are executed
for different values of the Rayleigh number based on the cylinder diameter, as well as

In this paper, numerical investigation of two-dimensional conjugate heat transfer of laminar wall jet flow over a shallow cavity heated from the bottom of the solid wall is carried out. The flow and conjugate heat transfer behaviors, isotherm contour in the cavity region, isotherm contour on the solid, interface temperature, local Nusselt number (local Nu), and average Nusselt number (average Nu) are investigated for various parameters, viz., Re, AR, Xu, and b. The momentum of the fluid is gradually reduced when the step length Xu is increased.

The flow and heat transfer behavior of laminar incompressible slot jets impingement cooling of an array of heated surfaces in a channel have been investigated numerically. The computations are done for a variety of values of slot jets Reynolds number, channel height and distance between two heated blocks. The influences of these geometrical and physical parameters are predicted. The results, streamline contour, velocity profile, isothermal contour, local Nusselt number, and average Nusselt number are compared and documented.

The Water Cooled Lithium Lead (WCLL) breeding blanket concept is the one of
the PbLi-based concepts under development within the framework of the EUROfusion
project. This concept is characterized by cooling the PbLi using water tubes embedded in
the PbLi flow. In this work, the MHD coupling between the conductive tubes walls and the
PbLi flow is studied for the geometrical and operational configuration of the WCLL.
Velocity profiles are computed first considering a toroidal magnetic field using a fully

In “An Approach to Verification and Validation of MHD Codes for Fusion Applications” [S. Smolentsev et al., Fusion Eng. Des., Vol. 100, p. 65 (2015)], an effort for verification and validation of computer codes for liquid metal flows in a magnetic field for fusion cooling/breeding applications was initiated. The current study continues that effort.

Solid Oxide Fuel Cells (SOFCs) have shown unique performance in terms of greater electrical efficiency and thermochemical integrity with the power systems compared to gas turbines and internal combustion engines. Nonetheless, simple and reliable models still must be defined. In this paper, a comparison between a grey-box model and a 1-D model of a SOFC is performed to understand the impact of the heat transfer inside the cell on the internal temperature distribution of the solid electrolyte.

To minimize MHD pressure drops, the liquid metal in a fusion blanket can be employed just as tritium breeder, whereas a non-conductive secondary fluid is used as coolant. The coolant can be carried in the breeding zone by pipes that, being transversal to the streamwise direction, affect the flow features and heat transfer.

The monitoring of waste disposal sites is important in order to minimize leakages of biogas, produced by anaerobic digestion and potentially explosive and detrimental to the environment. In this research, UAV-based thermal imaging has been proposed as a diagnostic tool to monitor urban landfills. Since the anaerobic decomposition produces heat along with biogas, thermal anomalies recorded over the soil are likely to be associated with local biogas escaping from the landfill terrain and leaving a local thermal print.