ITTC – Recommended 7.5-04 -01-01.1 Procedures and Guidelines Page 1 of 76 Preparation, Conduct and Analysis of Effective Date Revision Speed/Power Trials 2017 05 ITTC Quality System Manual Recommended Procedures and Guidelines Procedure Preparation, Conduct and Analysis of Speed/Power Trials 7.5 Process Control 7.5-04 Full Scale Measurements 7.5-04-01 Speed and Power Trials 7.5-04-01-01.1 Preparation, Conduct and Analysis of Speed/Power Trials Updated / Edited by Approved Specialist Committee on Performance of 28th ITTC 2017 Ships in Service of the 28th ITTC Date 04/2017 Date 09/2017 ITTC – Recommended 7.5-04 -01-01.1 Procedures and Guidelines Page 2 of 76 Preparation, Conduct and Analysis of Effective Date Revision Speed/Power Trials 2017 05 Table of Contents 7.6.1 Ship’s track and speed over ground 1. PURPOSE .............................................. 5 .................................................... 13 2. DEFINITIONS ....................................... 6 7.6.2 Torque ........................................ 13 7.6.3 Wind ........................................... 13 3. RESPONSIBILITIES ............................ 7 7.6.4 Water depth ................................ 14 3.1 Shipbuilders’ responsibilities ........... 7 7.6.5 Waves ......................................... 14 3.2 The Trial Team’s responsibilities ..... 7 7.6.6 Density and temperature ............. 14 7.6.7 Current ........................................ 14 4. TRIAL PREPARATIONS .................... 8 4.1 Installation & Calibration ................ 8 8. CONDUCT OF TRIAL ....................... 14 4.2 S/P trial agenda and pre-trial 8.1 Initiation ........................................... 14 meeting ................................................ 9 8.2 Trial trajectory ................................ 15 5. SHIP CONDITION ............................... 9 8.3 Run duration and timing ............... 15 5.1 Displacement ...................................... 9 8.4 Trial direction .................................. 15 5.2 Trim .................................................. 10 8.5 Steering ............................................. 15 5.3 Hull &propeller ............................... 10 8.6 Approach .......................................... 15 8.7 Power settings .................................. 16 6. TRIAL BOUNDARY CONDITIONS 10 8.8 Number of speed runs ..................... 16 6.1 Location ............................................ 10 8.8.1 ‘Iterative’ method ....................... 16 6.2 Wind .................................................. 10 8.8.2 ‘Mean of means’ method ............ 16 6.3 Sea state ............................................ 11 8.8.3 Sister ships .................................. 16 6.4 Water depth ..................................... 11 8.8.4 Additional runs due to limiting wave height ................................ 16 6.5 Current ............................................. 11 8.9 Test sequence ................................... 17 7. TRIAL PROCEDURES ...................... 12 9. DATA ACQUISITION ....................... 17 7.1 Parameters that shall be recorded . 12 9.1 Acquisition system ........................... 17 7.2 Primary parameters ........................ 12 9.1.1 System requirements .................. 17 7.3 Secondary parameters ..................... 12 9.1.2 Location ...................................... 18 7.4 General information ........................ 13 9.2 Manual data collection .................... 18 7.5 Model test information .................... 13 9.3 Sign convention ................................ 18 7.6 Scope and conduct of the measurements .................................. 13 10. ANALYSIS PROCEDURE ................ 19 10.1 General Remarks ............................. 19 ITTC – Recommended 7.5-04 -01-01.1 Procedures and Guidelines Page 3 of 76 Preparation, Conduct and Analysis of Effective Date Revision Speed/Power Trials 2017 05 10.2 Description of the Analysis : PROPULSIVE Procedure ......................................... 19 EFFICIENCY CORRECTION BASED 10.2.1 Resistance data derived from the ON LOAD VARIATION TESTS ....... 36 acquired data ............................... 21 D.1. Propulsive efficiency correction ...... 36 10.2.2 Evaluation of the acquired data .. 21 D.2. Correction of shaft rotation rate – 10.2.3 Evaluation based on Direct Power effect of added resistance and of Method ...................................... 21 shallow water ................................... 36 10.2.4 Correction of the measured ship’s speed due to the effect of current 22 : EVALUATION OF WIND 10.2.5 Prediction of power curve from DATA .................................................... 38 trial condition to other loading E.1. Averaging process for the true wind condition ..................................... 23 vectors ............................................... 38 10.3 Calculation methods for resistance E.2. Correction for the vertical position of increase and other corrections........ 23 the anemometer ............................... 39 10.3.1 Resistance increase due to the effects of wind ............................ 23 : CORRECTION METHODS FOR RESISTANCE INCREASE DUE 10.3.2 Resistance increase due to the TO WIND ............................................. 41 effects of waves .......................... 24 10.3.3 Resistance increase due to water F.1. Wind resistance coefficients by wind temperature and salt content ....... 25 tunnel test ......................................... 41 10.3.4 Correction of the ship performance F.2. Wind resistance coefficients by CFD .. due to the effects of shallow water. ....................................................... 41 ...................................... 25 F.3. Data sets of wind resistance 10.3.5 Correction of the ship’s coefficients ........................................ 41 performance due to the effects of displacement ............................... 26 F.4. Regression formula by Fujiwara et al. ....................................................... 52 11. PROCESSING OF THE RESULTS .. 26 : CORRECTION 12. REPORTING ....................................... 29 METHODS FOR RESISTANCE INCREASE DUE TO WAVES .......... 54 13. REFERENCESAND G.1. Simplified correction method for BIBLIOGRAPHY ................................ 30 ships with limited heave and pitch during the speed runs (STAWAVE- : GENERAL SHIP AND 1) ....................................................... 54 TRIAL DATA ...................................... 32 G.2. Empirical correction method with : BEAUFORT SCALE OF frequency response function for ships WIND .................................................... 33 with heave and pitch during the speed runs (STAWAVE-2) ............. 54 : FORMAT S/P TRIAL LOG SHEET .................................................. 35 ITTC – Recommended 7.5-04 -01-01.1 Procedures and Guidelines Page 4 of 76 Preparation, Conduct and Analysis of Effective Date Revision Speed/Power Trials 2017 05 G.3. Theoretical method with simplified : RAVEN SHALLOW- tank tests in short waves or empirical WATER CORRECTION ................... 71 formula ............................................. 56 K.1. Calculation of viscous resistance .... 71 G.4. Seakeeping model tests .................... 59 K.2. Shallow-water correction of viscous re-sistance ......................................... 72 : EFFECT OF CURRENT 60 K.3. Estimate additional sinkage ............. 72 H.1. ‘Iterative’ method ............................ 60 K.4. Estimate resulting additional H.2. ‘Mean of means’ method ................. 61 displacement ..................................... 72 : CONVERSION FROM K.5. Estimate resistance increase caused TRIAL SPEED/POWER TEST by additional sinkage in shallow RESULTS TO OTHER STIPULATED water ................................................. 72 LOAD CON-DITIONS ....................... 63 K.6. Correct measured power ................. 72 : EXTENDED ANALYSIS K.7. Check validity of calculated viscous OF DIRECT POWER METHOD resistance .......................................... 72 (INFOR-MATIVE) .............................. 64 K.8. Limits of applicability: ..................... 73 J.1. Propulsive efficiency correction ....... 64 J.2. Application of load variation test NOMENCLATURE ........... 74 results ................................................ 70 ITTC – Recommended 7.5-04 -01-01.1 Procedures and Guidelines Page 5 of 76 Preparation, Conduct and Analysis of Effective Date Revision Speed/Power Trials 2017 05 Preparation, Conduct and Analysis of Speed/Power Trials • the trial procedure, • the execution of the trial, 1. PURPOSE • the measurements required, The primary purpose of speed-power trials is • the data acquisition and recording, and to determine ship performance in terms of speed, • the processing of the results. power and propeller revolutions under pre- scribed ship conditions, and thereby verifying The contracted ship’s speed and the speed the satisfactory attainment of the contractually for EEDI shall be determined for stipulated con- stipulated ship’s speed and power and to provide ditions which are defined at specific draughts the ship’s speed and power for the calculation of (contract draught and EEDI draught) and usu- the Energy Efficiency Design Index (EEDI) as ally for ideal environmental conditions i.e. no required by IMO. wind, no waves, no current, deep water. The present Recommended Procedure con- Normally, such stipulated conditions are not cerns the preparation and execution of speed- experienced during the actual trials.