In a Modular High Temperature Gas Reactor (MHGTR), the Pressurized Conduction Cooldown (PCC) event is an accident scenario in which there is a loss of forced convection of the coolant through the system but the pressure boundary remains intact. When the PCC event occurs, natural circulation onsets which results in...
Sodium cooled nuclear reactors are being considered for the next generation of nuclear power plants to provide clean electricity to the world. To prove the safety of these reactors, the fuel must be shown to safely handle large neutron fluxes that cause a spike in the thermal output of the...
Hydrogen is an increasingly attractive low-carbon energy carrier for a variety of stationary and mobile applications. Currently, the vast majority of hydrogen in the United States is produced via the energy intensive steam reforming of natural gas. The cost and carbon emissions associated with hydrogen production can be reduced by...
Large amounts of energy are wasted when conditioned air in buildings is exhausted to meet ventilation requirements. There are several technologies to recover some of this energy, including the recent development of membrane based energy recovery ventilators (ERVs). ERVs exchange sensible heat and moisture between incoming fresh and outgoing exhaust...
Predicting condensation flow regimes and the associated heat transfer and pressure drop in microchannels is critical for designing terrestrial and space systems for heating, cooling, power generation, and advanced manufacturing. It is well established that in flows approaching the microscale (Dh < 1 mm) gravity-dominated flow regimes become less relevant,...
With the continued decrease in size and subsequent increase in power of computer processors, thermal management in electronics is becoming more important than ever before. The chip heat densities are reaching new peaks (> 100 W cm-2) that current cooling methods are not able to keep up with. However, some...
This work investigates the in-tube condensation of low global warming potential (GWP) zeotropic refrigerant mixtures R448A, R450A, R452A, R454B and R454C. These refrigerants have been proposed for a wide range of commercial heating, ventilation, air-conditioning applications, but their heat and momentum transport phenomenon were not well understood. Thus, in this...
Seven decades of supercritical heat transfer research have not seen an attempt to characterize turbulent thermal transport in internal flows subject to asymmetric heating. Existing heat transfer models therefore do not account for phenomena that dictates thermal transport, in the proximity of the pseudo-critical point, for non-uniform heating. Additionally, past...