Transient heat-pipe modeling - A quasisteady, incompressible vapor model

Boundary Element Approach to Transient Heat Pipe Analysis

“…(13) must be chosen to be very small in order to capture the quick wall transient. Consequently, cAlL may not be large enough to justify neglecting the transient terms; and (2) during a very short time period after the transient starts, the change of the vapor velocity with respect to time may be too large [8] In this study the transient terms were compared to the convective terms at each time level based upon the information from the previous time level. If the transient terms were negligible compared to the convective terms, the program used the quasi steady state vapor model; otherwise, the transient vapor model was used.…”

“…Bowman et al [8] further extended the time warping concept to a transient heat pipe model with a quasi-steady and quasi-incompressible vapor flow. The quasi-incompressible assumption decoupJes the vapor continuity and momentum equations, resulting in a very simple numerical solution procedure.…”

Recent Advances in the Modeling and Applications of Nonconventional Heat Pipes

“…Bowman et al [4] presented a one-dimensional model in which the vapor flow, treated as a saturated vapor and not an ideal gas, was assumed to be incompressible in space but compressible in time. This model was improved by Bowman and Beran [5] Zuo and Faghri [7] developed a heat pipe model with quasi-steady, one-dimensional vapor flow and transient, two-dimensional heat conduction in the wall and wick.…”