Microscale Thermophysical Engineering · 1997 · 137 citations · 0 references
EngineeringMechanical EngineeringPhysicsFluid DynamicsHeat TransferThermodynamicsHeat FlowHeat Transfer AnalysisHeat Transfer FundamentalsHeat Transfer In FluidsHeat Transfer ModelingLaminar FlowBoundary Condition FormulationsConstant Heat Flux Boundary ConditionsKnudsen NumberLaminar Flow Heat TransferLaminar Flow SystemsNusselt NumberSlip FlowWall Heat Transfer
An analytical solution to the problem of laminar gas flow in microtubes with a constant heat flux boundary condition at the wall is presented. The microtube diameter is small enough that the Knudsen number becomes an important parameter; thus, both a slip flow hydrodynamic condition and a temperature jump thermal condition are assumed at the wall. The fluid is assumed to be hydrodynamically fully developed at the tube entrance. An indirect solution method utilizes the solution for a previously reported isothermal wall problem. The results indicate that the fully developed Nusselt number decreases with Knudsen number. For instance, with a Knudsen number of 0.04, the Nusselt number for fully developed flow is reduced 14% over that obtained for a nonslip boundary condition. The reduction is strongly influenced by the increased temperature jump as Knudsen number increases. © 1997 Taylor & Francis Group, LLC.