A Comparison of 3-Bladed and 4-Bladed Inducers at On and Off[|#11#|] Design Flow Rates

Ryan Cluff, Ryan K. Lundgreen, Steven E. Gorrell, Daniel Maynes, Kerry Oliphant
2013 49th AIAA/ASME/SAE/ASEE Joint Propulsion Conference   unpublished
Concepts NREC, White River Junction, VT. 05001, USA A computational fluid dynamic comparison was performed between on-design and offdesign flow rates through a four-bladed and a three-bladed axial pump inducer. The simulations were run time-resolved and with two phases (water and water vapor). Turbulence modeling employed the realizable k-model and cavitation was predicted using the Rayleigh-Plesset model. The solution discretization is second order accurate in space and first order accurate in
more » ... t order accurate in time. The results show classical breakdown curves for all four cases. Breakdown is the condition where the entire flow path in the inducer becomes filled with vapor and the head rise over the inducer is decreased dramatically. The purpose of this paper is to compare performance behaviors between a three-bladed and four-bladed inducer operating at on-design and off-design flow rates. Certain rotating instabilities have previously been observed with the four-bladed inducer and we investigate whether similar instabilities exist for a three-bladed geometry. We also investigate how off-design operation affects the stability of both inducer geometries. Figure 4. Head coefficient (ψ), normalized by the on-design four-blade non-cavitating case, as a function of cavitation number (σ) for three-blade and four-blade inducers at 100% and 60% flow. Figure 5. Maximum rotor force, normalized by the on-design four-blade non-cavitating case, as a function of cavitation number (σ) for three-blade and four-blade inducers at 100% flow. (a) three-blade, σ = 0.0377, taken over 5.1 revolutions (b) three-blade, σ = 0.139, taken over 0.8 revolutions Figure 9. Sequence of contour plots of vapor fraction at 98% span over time on three-blade inducer at 60% flow. Figure 10. Sequence of contour plots of vapor fraction at 98% span for three-blade inducer at σ ≈ 0.019 over a period of 1.7 revolutions 11 of 12 American Institute of Aeronautics and Astronautics Downloaded by Steven Gorrell on August 7, 2013 | http://arc.aiaa.org |
doi:10.2514/6.2013-3761 fatcat:4v7474qktfadtebymz3xvkczva