Accession Number : ADA620901


Title :   Turning Vanes in Exhaust Duct Flow: Study for Energy Efficiency, Optimization and Pressure Drop Mitigation


Descriptive Note : Master's thesis


Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA


Personal Author(s) : Beale, Mark A


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a620901.pdf


Report Date : Sep 2014


Pagination or Media Count : 81


Abstract : This thesis presents a computational fluid dynamics (CFD) study on the effects of turning vanes and their placement in an exhaust duct with a sharp bend of ninety degrees and the application toward waste heat recovery devices. CFD models were implemented in ANSYS/CFX to handle flow in both laminar and turbulent regimes. Applying the principles from the Reynolds-averaging Navier-Stokes governing equations as well as the k-epsilon turbulent model, accurate simulations were performed to explore the behavior of exhaust gas flow field, pressure drops and recirculation zone sizes for various flow Reynolds (Re) numbers. The effects of turning vane location, vane setting angle, and number of vanes were evaluated. Flow visualization was used as a means of determining ideal locations for future installation of WHR devices. Results for 5000Re2x10(5) showed significant improvement in pressure drop across the 90-degree duct with a single turning vane, showing ranges of 50-70% reduction in overall pressure drop across the duct. This pressure reduction could yield significant fuel savings compared to an engine or generator without a turning vane. Increasing the number of vanes neither reduced the pressure drop further, nor did it reduce the size of the primary recirculation zone.


Descriptors :   *COMPUTATIONAL FLUID DYNAMICS , ENERGY , EXHAUST SYSTEMS , FLOW VISUALIZATION , GAS FLOW , HEAT RECOVERY , LAMINAR FLOW , PRESSURE , THESES


Subject Categories : Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE