An Investigation of Venturi and Coanda Effects in Blown Film Cooling
-
V. Sidiropoulos
and J. Vlachopoulos
Abstract
Numerical simulation of turbulent air flow tangentially impinging on a blown film bubble has been carried out. The cooling air is assumed to originate from a dual orifice adjustable air-ring. The stream line pattern and heat flux are determined through a finite volume numerical technique using a version of the so called k-∊ modeling. It is shown that as the air flows through the air ring passage relatively large under-pressure is created (Venturi effect), which applies a suction to the bubble. Depending on the flow rates and geometrical configurations the air jet may attach itself (Coanda effect) to either the air ring surface and/or to the bubble. The Coanda effect has a significant influence on local heat flux. The numerical results suggest that the Venturi and Coanda effects influence significantly process stability, production rate and final film properties.
© 2000, Carl Hanser Verlag, Munich
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- Computer Aided Optimisation of Profile Extrusion Dies
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- An Investigation of Venturi and Coanda Effects in Blown Film Cooling
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- Comparative Study of Ziegler-Natta and Metallocene Based Polypropylenes in Injection Molding
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Articles in the same Issue
- Editorial
- Sixth of a Series: Pioneer of Man-Made Fibers and Solution Spinning Louis-Marie-Hilaire Bernigaud, Comte de Chardonnet
- Screw Extrusion
- A Network Analysis of a Screw Mixing Zone
- Experimental and Numerical Study of Rhomboidal Mixing Sections
- Reactive Extrusion
- Bulk Polymerization of ∊-Caprolactone in Twin Screw Extruder
- Die Extrusion
- Computer Aided Optimisation of Profile Extrusion Dies
- Fibers and Films
- An Investigation of Venturi and Coanda Effects in Blown Film Cooling
- Blends
- Solidification Behaviour of PA6/iPP Blends at High Cooling Rates
- Polymer Blends with Fibrillar Phase Morphology Prepared by Self-Reinforcing Technique
- Molding
- Compressive Squeeze Flow of Generalized Newtonian Fluids with Apparent Wall Slip
- Comparative Study of Ziegler-Natta and Metallocene Based Polypropylenes in Injection Molding
- The Pressure-Volume-Temperature Behavior Polyethylene Melts
- Evaluation of the Thermal Behaviour of Injection Moulds
- Polymer Solidification under Pressure and High Cooling Rates