... is typically in hours, but on the other hand, the time-step sizes typically usable tend to be very small (subseconds) due to the numerical stability requirement for natural convection as often observed. An issue of interest is: What time-step sizes can and should be used in terms of stability as well...

... manuscript received May 21, 2017; published online June 21, 2017. Assoc. Editor: Liang Tang. 05 12 2016 21 05 2017 Aeronautical propulsion Aerospace applications Engines Heat transfer Natural convection Component maintenance Component operations Aerospace Propulsion systems...

... by surfaces with different temperatures, here T 1 and T 2 . When there is a temperature gradient between both surfaces, a heat flux will occur. The overall heat flux is the sum of the different heat transfer mechanisms: natural convection, forced convection, and radiation. After summing-up the heat...

.... Finite element Heat transfer Mass Transfer Natural convection Power Radiation Temperature Thermodynamics Turbines Unsteady Co- generation The temperature drop during natural cooling and the way in which the steam turbine restarts have a major impact on the cyclic lifetime of critical...

... reactor cooling fission reactor core control natural convection thermal expansion Natural circulation plays a well-known role in many design concepts proposed for future nuclear reactors (see, e.g., Ref. 1 ). This is the consequence of its suitability as a passive mechanism of core cooling...

... play an important role during natural convection with the ECC injection in PWR and should be also considered in pressurized thermal shock scenarios. ANSYS CFX was able to predict the observed flow patterns and mixing phenomena quite well. Since coolant mixing is mainly caused by turbulent...