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Hydrograph_and_Unit_Hydrograph_Presentation (2).pptx
- 1. Hydrograph and UnitHydrograph Research-Level Presentation Modern Visual Theme with Diagrams and APA References
- 2. Table of Contents •1. Introduction • 2. Hydrologic Cycle and Runoff • 3. Definition of Hydrograph • 4. Components of a Hydrograph • 5. Factors Affecting Hydrograph Shape • 6. Types of Hydrographs • 7. Analysis of Hydrograph • 8. Flow Separation • 9. Base Flow Concept
- 3. Introduction • • Hydrologydeals with the movement and management of water. • • Hydrographs and Unit Hydrographs are vital tools. • • Used for flood prediction, watershed modeling, and water resource design.
- 4. Hydrologic Cycle andRunoff • • Continuous circulation of water on Earth. • • Runoff occurs when rainfall exceeds infiltration. • • Hydrographs quantify this runoff with respect to time.
- 5. Definition of Hydrograph •• Graph showing discharge (Q) versus time (t). • • Represents basin response to rainfall. • • X-axis: Time; Y-axis: Discharge.
- 6. Components of aHydrograph • • Rising limb, peak discharge, recession limb, base flow, lag time. • • Reflects basin’s hydrologic behavior.
- 7. Factors Affecting Hydrograph Shape •• Basin size and shape • • Land use and vegetation • • Soil type • • Rainfall intensity and duration
- 8. Types of Hydrographs •• Storm hydrograph – from a single rainfall. • • Annual hydrograph – yearly variation. • • Baseflow hydrograph – groundwater contribution.
- 9. Analysis of Hydrograph •• Used for flood peak, time to peak, and basin response. • • Important for reservoir and drainage design.
- 10. Flow Separation • •Separates base flow and direct runoff. • • Methods: Graphical or analytical.
- 11. Base Flow Concept •• Represents sustained groundwater contribution. • • Important in low-flow conditions.
- 12. Applications of Hydrograph •• Flood forecasting • • Reservoir operation • • Watershed management • • Urban drainage planning
- 13. Limitations of HydrographAnalysis • • Assumes consistent basin response. • • Sensitive to rainfall data accuracy. • • Land use changes not directly represented.
- 14. Introduction to UnitHydrograph • • Direct runoff from 1 cm (or 1 mm) of effective rainfall. • • Linear system response of the basin.
- 15. Assumptions of UnitHydrograph Theory • • Linearity, superposition, time invariance, uniform distribution. • • Simplifies rainfall-runoff modeling.
- 16. Derivation of UnitHydrograph • • Derived from rainfall-runoff data. • • Steps: Determine effective rainfall, compute direct runoff, normalize to 1 unit.
- 17. Effective Rainfall andDirect Runoff • • Effective rainfall = total rainfall - losses (infiltration, evaporation). • • Produces direct runoff hydrograph.
- 18. Unit Hydrograph Ordinates •• Represent discharge at intervals. • • Used to compute hydrographs for any rainfall by scaling.
- 19. S-Curve Method • •Used to derive UHs for different durations. • • Based on cumulative response principle.
- 20. Instantaneous Unit Hydrograph (IUH) •• Represents response to an infinitesimal rainfall. • • Theoretical but used in advanced models.
- 21. Synthetic Unit Hydrograph •• Derived using empirical formulas. • • Examples: Snyder’s, SCS, Nakayasu methods.
- 22. Examples and Applications •• Used for flood forecasting and storm design. • • A core part of watershed management models.
- 23. Case Study Example •• Demonstration using observed rainfall- runoff data. • • Validation through superposition and scaling.
- 24. Comparison between Hydrograph andUnit Hydrograph • • Hydrograph: Actual discharge-time relation. • • Unit Hydrograph: Response to 1 unit rainfall. • • UH = normalized hydrograph.
- 25. Limitations of UnitHydrograph • • Assumes linearity and time invariance. • • Ineffective for heterogeneous or large basins.
- 26. Modern Approaches • •Machine learning, AI, and remote sensing. • • Integrating new data sources for improved accuracy.
- 27. AI and Data-drivenModels • • Neural networks, SVM, LSTM models improve rainfall-runoff prediction. • • Non-linear relationships better captured.
- 28. GIS in Hydrology •• Enables watershed delineation and analysis. • • Integrates spatial data for modeling.
- 29. Climate Change andHydrograph Shifts • • Alters rainfall patterns and runoff. • • Requires adaptive hydrologic models.
- 30. Future Research Directions •• AI-based modeling, data assimilation. • • Climate impact studies, real-time flood modeling.
- 31. Summary • • Hydrograph:runoff over time. • • Unit Hydrograph: response to 1 unit rainfall. • • Both crucial for flood forecasting and basin analysis.
- 32. References • • Chow,V. T., Maidment, D. R., & Mays, L. W. (1988). Applied Hydrology. McGraw-Hill. • • Linsley, R. K., Kohler, M. A., & Paulhus, J. L. (1982). Hydrology for Engineers. McGraw-Hill. • • Singh, V. P. (1997). Hydrologic Systems: Rainfall-Runoff Modeling. Prentice-Hall. • • Subramanya, K. (2017). Engineering Hydrology. McGraw-Hill Education.