Accession Number : ADA268012


Title :   Flow Instability Tests for a Particle Bed Reactor Nuclear Thermal Rocket Fuel Element


Descriptive Note : Master's thesis,


Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING


Personal Author(s) : Lawrence, Timothy J


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a268012.pdf


Report Date : May 1993


Pagination or Media Count : 351


Abstract : Recent analyses have focused on the flow stability characteristics of a particle bed reactor (PBR). These laminar flow instabilities may exist in reactors with parallel paths and are caused by the heating of the gas at low Reynolds numbers. This phenomena can be described as follows: several parallel channels are connected at the plenum regions and are stabilized by some inlet temperature and pressure; a perturbation in one channel causes the temperature to rise and increases the gas viscosity and reduces the gas density; the pressure drop is fixed by the plenum regions, therefore the mass flow rate in the channel would decrease; the decrease in flow reduces the ability to remove the energy added and therefore the temperature increases; and finally, this process could continue until the fuel element fails. Several analyses based on different methods have derived similar curves to show that these instabilities may exist at low Reynolds numbers and high phi's ((Tfinal Tinitial)/Tinitial). These analyses need to be experimentally verified.


Descriptors :   *THERMAL PROPERTIES , *STABILITY , *FLOW RATE , *ROCKET FUELS , DENSITY , PATHS , THESES , GASES , MASS FLOW , PRESSURE , NUCLEAR PROPERTIES , REYNOLDS NUMBER , CHANNELS , INLETS , LAMINAR FLOW , VISCOSITY , PARALLEL ORIENTATION , PERTURBATIONS , REACTOR SYSTEM COMPONENTS , PLENUM CHAMBERS , NUCLEAR PHYSICS , HEATING , PARTICLES , FUELS , REGIONS , RATES , ENERGY , TEMPERATURE


Subject Categories : Fission Reactor Materials
      Fluid Mechanics
      Nuclear Physics & Elementary Particle Physics
      Thermodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE