Description
Book SynopsisExamining a range of case studies involving different types of systems and the types of surge suppression equipment which may be suited to each, this practical book provides an indepth analysis of actual systems, with emphasis on the type of hydraulic transient behaviour to be expected in each kind of configuration.
Table of ContentsIntroduction. 1. Motivation for Hydraulic Transient Analysis. Primary Purpose of Analysis. Secondary Objectives. Permitted Pressures. Maximum Pressures. Pipe Materials. Rigid Pipes. Grey Cast Iron. Asbestos Cement. Concrete Pipes. Flexible Pipes. Ductile Iron. Steel Pipe. Overpressure Allowance. Pipe Linings for Rigid & Flexible Pipes. Bitumen. Coal Tar Enamel. Coal Tar Epoxy Lining. Cement Mortar. Paint Systems. Polyethylene Lining. Plastic Pipes. Thermosetting Plastics. Thermoplastics. Failure Modes of Pipes. Maximum Pressure & Allowable Amplitude of Surge in Plastic Pipes. Minimum Pressures. 2. Derivation of Basic Equations. 2.1 The Rigid-Column Approach. 2.2 Compressible Flow Theory. 2.2.1 Conservation of Force. 2.2.2 Conservation of Mass. 2.2.3 Compressible Flow Equations in Terms of Total Head `H’. 3. Interpretation of `a’. Fluid Properties. Influence of the Conduit Wall. Simple Expression for `a’. Variation of `a’ with Conduit Shape. Influence of Gas on `a’. 3.6 The Effect of Sewage. 4. Characteristic Equations. Development of Characteristic Equations. Significance of the Integrals. Effect of Changing Pipe Elevation. Pipeline Resistance. Corrosion. Sliming. Evaluation of the Integral. 5. Application of Characteristic Equations. Use of the Characteristics. “Natural” Characteristic Mesh. Using Variable Wavespeed `a’. Use of a Larger Time Step. Use of a Fixed Wavespeed. Distribution of Free Gas along the Pipeline. Model Output. 6. Boundaries. Types of Boundaries. Reservoirs and Tanks. Branches & Changes in Pipe Properties. Specific Cases – number of pipes = 1. Specific Cases – change of cross-sectional area. Response of a Large Pipe or Trunk Main. Actuated Valves & Pipeline Fittings. Terminal Valves. In-line Valve. Automatic Control Valves. Pressure Reducing Valve. Pressure Sustaining Valve. Demand Sensing Pressure Reducing Valve. Use of More then One Time Step. Non-reflecting Boundary. Other Bifurcation Conditions. Bifurcation with Operating Valves. Isolating Valves. Continuous Drawoff. 7. Valve Closure in a Simplified System. Instantaneous Valve Closure at t = 0. From 0 < t = L/a. L/a < t = 2.L/a. 2.L/a < t = 3.L/a. 3.L/a < t = 4.L/a. 8. Actual Pipelines & Valve Movements. Attenuation. Conditions at the Wavefront. Conditions when the Wavefront is of Zero Amplitude. Conditions at the Closed Valve. Conditions Downstream of a Pump or Valve. A Uniform Gravity Main. 9. Valve Operations. Treated Water Main. Improving Valve Operation. Two-stage Valve Closure. Submerged Discharge Valve. In-line Valves. Isolating Valves. Actuated Valve. Control of Transient Pressures & Estimation of Valve Operating Time. 10. Pumps. Types of Pump. Turbine Pumps. Centrifugal or Radial Flow Pumps. Mixed or Semi-axial Flow Pumps. Axial Flow or Propeller Pumps. Turbine Pump Performance Curves. Including Turbine Pumps in Hydraulic Transient Analyses. Transfer Pump. Booster Pump. Other Pumping Station & Pipeline Configurations. Station Losses. System Curves & Pump Duty. Turbine Pump Start. Direct Start. Star/delta & Transformer Starting. Variable Speed or “Soft” Start. Case Studies of Pump Start. Simulation of Direct Start in Solo Pumping. Direct Start in Multi-pump Operation. Initial Conditions of Flow. Pump Failure or “Trip”. Other Pumps. Reciprocating Pumps. Pneumatic Ejector. The Hydraulic Ram. The Jet Pump. 11. Flywheels. Moment of Inertia. Flywheels. Limitations on Flywheel Size. Pipeline Limitations. Case Study with Different Pump Speed Options. Flywheels on a Larger System. Booster Pump Installations. Multi-pump Installations.
