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Delft Hydraulics Prepared for: DG Rijkswaterstaat, Rijksinstituut voor Kust en Zee | RIKZ Description of TRANSPOR2004 and Implementation in Delft3D-ONLINE FINAL REPORT Report November 2004 Z3748.00 WL | delft hydraulics Prepared for: DG Rijkswaterstaat, Rijksinstituut voor Kust en Zee | RIKZ Description of TRANSPOR2004 and Implementation in Delft3D-ONLINE FINAL REPORT L.C. van Rijn, D.J.R. Walstra and M. van Ormondt Report Z3748.10 WL | delft hydraulics CLIENT: DG Rijkswaterstaat Rijks-Instituut voor Kust en Zee | RIKZ TITLE: Description of TRANSPOR2004 and Implementation in Delft3D-ONLINE, FINAL REPORT ABSTRACT: In 2003 much effort has been spent in the improvement of the DELFT3D-ONLINE model based on the engineering sand transport formulations of the TRANSPOR2000 model (TR2000). This work has been described in Delft Hydraulics Report Z3624 by Van Rijn and Walstra (2003). However, the engineering sand transport model TR2000 has recently been updated into the TR2004 model within the EU-SANDPIT project. The most important improvements involve the refinement of the predictors for the bed roughness and the suspended sediment size. Up to now these parameters had to be specified by the user of the models. As a consequence of the use of predictors for bed roughness and suspended sediment size, it was necessary to recalibrate the reference concentration of the suspended sediment concentration profile. The formulations (including the newly derived formulations of TR2004) implemented in this 3D-model are described in detail. The implementation of TR2004 in Delft3D-ONLINE is part of an update of Delft3D which involves among others: the extension of the model to be run in profile mode, the synchronisation of the roughness formulations and inclusion of two breaker delay concepts. The present report describes the implementation of TR2004 formulations in Delft3D-ONLINE in detail. REFERENCES: Overeenkomst RKZ-1392 VER. ORIGINATOR DATE REMARKS REVIEW APPROVED BY 1 Walstra 18 May 2004 Draft Van Rijn van der Weck 2 Walstra 28 May 2004 Interim Van Rijn van der Weck 3 Walstra 11 November 2004 Final Van Rijn Schilperoort PROJECT IDENTIFICATION: Z3748 KEYWORDS: TRANSPOR2004, Delft3D, Breaker Delay NUMBER OF PAGES 78 CONFIDENTIAL: YES, until (date) NO STATUS: PRELIMINARY DRAFT FINAL Description of TRANDPOR2004 and Implementation in Delft3D-ONLINE Z3748.10 November, 2004 FINAL REPORT Contents 1 Introduction ................................................................................................... 1—1 2 UPDATED TRANSPOR2004-MODEL ...................................................... 2—1 2.1 Introduction.........................................................................................................2—1 2.2 Updated sand transport model TRANSPOR2004 (TR2004) ..........................2—1 2.2.1 Bed roughness predictor ..........................................................................2—1 2.2.2 Predictor for suspended sediment size.....................................................2—4 2.2.3 Thickness of wave-boundary layer, fluid mixing and sediment mixing layer .........................................................................................................2—4 2.2.4 Wave-induced bed-shear stress................................................................2—5 2.2.5 Wave-induced streaming..........................................................................2—6 2.2.6 Shields criterion for initiation of motion .................................................2—6 2.2.7 Bed-load transport ...................................................................................2—7 2.2.8 Wave-related suspended transport ...........................................................2—8 2.2.9 Near-bed sediment mixing coefficient.....................................................2—8 2.2.10 Reference concentration and reference level ...........................................2—8 2.2.11 Recalibration............................................................................................2—9 2.3 Intercomparison of transport rates based on TR2004 with TR2000 and TR1993...............................................................................................................2—15 2.4 Application of TR2004-model for graded sediment.......................................2—17 2.4.1 Experiments ...........................................................................................2—17 2.4.2 Model results .........................................................................................2—20 3 Sand transport formulations in DELFT3D model..................................... 3—1 3.1 Introduction.........................................................................................................3—1 3.2 Model description ...............................................................................................3—2 3.2.1 Hydrodynamics........................................................................................3—2 WL | Delft Hydraulics i Description of TRANDPOR2004 and Implementation in Delft3D-ONLINE Z3748.10 November, 2004 FINAL REPORT 3.2.2 Waves.......................................................................................................3—8 3.2.3 Sediment dynamics and bed level evolution............................................3—9 3.2.4 Erosion and deposition...........................................................................3—20 3.2.5 Wave-related suspended transport .........................................................3—24 3.2.6 Bed load transport..................................................................................3—26 3.2.7 Transport Calibration Factors ................................................................3—27 3.3 Implementation Check of TR2004 in Delft3D................................................3—28 3.4 Miscellaneous Improvements to Delft3D ........................................................3—28 4 Conclusions .................................................................................................... 4—1 5 References ...................................................................................................... 5—1 WL | Delft Hydraulics ii Description of TRANDPOR2004 and Implementation in Delft3D-ONLINE Z3748.10 November, 2004 FINAL REPORT 1 Introduction RIKZ of Rijkswaterstaat and Delft Hydraulics are working together on the development/improvement, verification/validation and evaluation of morphodynamic models within the framework K2005 of Rijkswaterstaat (see Report Z2478 of Delft Hydraulics and Website http://vop.wldelft.nl) and within the SANDPIT-project (website: http://sandpit.wldelft.nl). In 2003 much effort has been spent in the improvement of the DELFT3D-ONLINE model based on the engineering sand transport formulations of the TRANSPOR2000 model (TR2000). This work has been described in Delft Hydraulics Report Z3624 by Van Rijn and Walstra (2003). However, the engineering sand transport model TR2000 has recently been updated into the TR2004 model within the EU-SANDPIT project. The most important improvements involve the refinement of the predictors for the bed roughness and the suspended sediment size. Up to now these parameters had to be specified by the user of the models. As a consequence of the use of predictors for bed roughness and suspended sediment size, it was necessary to recalibrate the reference concentration of the suspended sediment concentration profile. Given the updated TR2004 model, an effort was necessary to further improve the DELFT3D-ONLINE model using the formulations of the updated TR2004 sand transport model (see Chapter 2). This latter work has been reported in Chapter 3. Chapter 2 addresses the description of the updated TR2004 model and the recalibration of the reference concentration using field and laboratory data sets. Furthermore, the results of the TR2004 model have been compared with results from older versions (TR1993 and TR2000) of the sand transport model Chapter 3 addresses the central focus point of the study: the DELFT3D-ONLINE model. The formulations (including the newly derived formulations of TR2004) implemented in this 3D-model are described in detail. The implementation of TR2004 in Delft3D-ONLINE is part of an update of Delft3D which involves among others: the extension of the model to be run in profile mode, the synchronisation of the roughness formulations and inclusion of two breaker delay concepts. The present report describes the implementation of TR2004 formulations in Delft3D-ONLINE in detail. Some general conclusions are given in Chapter 4. WL | Delft Hydraulics 1—1 Description of TRANDPOR2004 and Implementation in Delft3D-ONLINE Z3748.10 November, 2004 FINAL REPORT 2 UPDATED TRANSPOR2004-MODEL 2.1 Introduction A new version of the TRANSPOR model has been made (TR2004) based on the results of former studies, particularly those of 2003 (Van Rijn and Walstra, 2003). The basic formulations of the TR1993-model are described in Appendix A of Van Rijn (1993). Detailed information on the Multi-fraction method can be found in Van Rijn (2000). The modifications concern the following points: • Predictor of bed roughness; • Predictor of suspended sediment size • Grain roughness and friction factor; • Wave-induced orbital velocities and streaming near the bed; • Wave-induced bed-shear stress; • Wave-induced sand transport; • Shields criterion for fine sand; • Bed load transport model • Mixing near the bed; • Reference concentration. In 2003 new bed roughness predictors to simulate the effective
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