Berechnung der dreidimensionalen Geschwindigkeitsverteilung in Rohrbündel‐Wärmeübertragern und Simulation der Schwingungsanregung

Simulation of the Two-Phase Secondary Flow in an Acetylene Cooler

“…The application of overheated vapors (solvent vapors, steam) as the drying medium in the process industry [2,3] turns out to be much more sluggished, although the possibility of drying with vapor in a closed cycle has been known since HAUSBRAND's work [1] in 1898.…”

“…It is known that the gap flow through the tube sheet is driven by pressure loss Dp. The velocity distribution in the gap can be calculated by (1) from the equilibrium of forces in the direction of the flow under the condition of a laminar flow. In the formula r I is the outer radius of the tube, r A is the radius of the hole, s is the thickness of the baffle and Z is the viscosity.…”

“…1) is valid under the following assumptions: ± The process runs continuously and adiabatically; ± The solid matter is ideally mixed; ± Ideal plug flow of the vapor; ± The wetting-degree model applies to the injected liquid; ± The fluidized bed is homogeneous (no bubble formation); ± The vapors flowing through the exhaust pipe and the gas distribution plate mix directly above the perforated plate; ± The material characteristics in the fluidized bed are constant. The model is derived from a simplified heat balance around a volume element in the fluidized bed: 1) (1)…”

“…In chemical plants the tube bundle heat exchanger is one of the most common and most investigated [1] components. Meanwhile two-phase flows [2] can also be investigated using commercial CFD program codes.…”

Dreidimensionale numerische Simulation strömungsinduzierter Rohrbündelschwingungen

“…Leitbleche werden dabei als Porositäten dargestellt. In [Ley93,Gel94,Urb94,Jah95,Gel98] werden Strömungsverteilungen in großen Wärmetauschern mit Hilfe von STAR-CD berechnet, um den Stabilitätsfaktor des Connors-Kriteriums zu bestimmen. In [Bir00] wird hierfür CFX verwendet.…”