Transcript Masters Project.pptx

Summary Presentation
Masters Project
JEFFREY STACK
December 2011
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Introduction
Problem Description
Methodology
Expected Results
Sizing of the Orifices
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Reactor Coolant Pumps (RCPs)
◦ Function
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Testing Requirements
◦ Characteristics that are tested
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Challenges to Testing
◦ Conditions
◦ Very specific requirements
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Net Positive Suction Head
◦ Very low pump suction pressures
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Harsh Testing Conditions for all Components
◦ In particular, NPSH testing conditions
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Cavitation in Restriction Orifice
◦ Large Δp & Large reduction in flow area
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Task – Dual Orifice System Design
◦ To minimize flow area reduction
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Hydraulic Design
◦ Includes sizing and any flow specific geometries
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Structural Design
◦ Includes static and dynamic analysis of the orifices
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Size Orifice & Determine Detailed Geometry
◦ Using Idelchick’s “Handbook of Hydraulic
Resistance”
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Create 3D Model
◦ Using ANSYS Workbench
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Perform Static Structural Analysis
◦ Using ANSYS Workbench by applying the Δp on the
front face of the orifice
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Perform Dynamic Structural Analysis
◦ Using ANSYS Workbench to determine orifice
natural frequencies
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Two Orifice System Minimizing Cavitation
Orifice System to be Capable of Testing at 2
Flow Points by Removal of One Orifice
Structurally Sound for all Testing Conditions
Natural Frequency not to Overlap Typical
Pump Blade Passing Frequencies
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Using the required Δp of 663.5kPa to achieve
the high flow point, Orifice 1 is sized using
the following correlation from Idelchick
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Where Fo is the flow area of the orifice which
is solved for
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The inner diameter of Orifice 1 is determined
to be 0.551m
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To determine the required Δp for Orifice 2, a new
Δp of Orifice 1 is calculated for the low flow point
This new Orifice 1 Δp is subtracted from the total
(Orifice 1 & 2 combined) Δp of 1143.0kPa, which
is required to achieve the low flow point
The Orifice 2 Δp is determined to be 890.4kPa
Using the correlation on the previous slide, the
Orifice 2 inner diameter is determined to be
0.448m
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