Parametric Investigation of Pressure Distribution on Wedge Water Entry by Experiment

Transcription

1 2 3 2 * ().... : Parametric Investigation of Pressure Distribution on Wedge Water Entry by Experiment H. Zeraatgar 1, E. Hassani Chalaksara 2, R.Yousefnejad 3, M. J. Javaherian 2 1Assistant professor, Faculty of Marine Technology, Amirkabir University of Technology. 2MSc student, Faculty of Marine Technology, Amirkabir University of Technology. 3PhD student, Faculty of Marine Technology, Amirkabir University of Technology. Abstract Analysis of wedge water entry as a basic problem has wide application. Model testing is a powerful means to deal with the said problem. In this study, a set of water entry tests on wedges of 20, 30 and 40 degrees deadrise angles has been conducted and the pressure distributions are recorded. Free falling method in symmetry conditions are considered in this research. A parametric study on pressure coefficients due to velocity and deadrise angles has been carried out on the wedge. Furthermore, Zparameter as a nondimensional factor defined for two individual parameters, time and depth of entry, has been evaluated. Finally, some comparison with numerical methods is presented. The kind of parametric study by means of model test may be regarded as the outcome of this study. Keywords: Wedge, Impact Velocity, Deadrise Angle, Pressure Distribution, Pressure Coefficient hamidz@aut.ac.ir : * /15 /

2 [4] [5] [6] [7] [8] [9] () [1] [2] 3.[3] /15 / 76

3 [10] ( ) /15 /

4 [11,12] 1 [m] 0/5 0/5 0/5 0/2 0/2 0/ / /9 3/1 ( ) psi. 0/001psi ( 4/4 ) /15 / 78

5 ( 3/1 ) 0/ ( 1/9 ) 0/ = : (1) (1) [ 9/972] 6 /90 [ 10 / 04] 2 /6 [ 9 / 932] 30 [psi] [ ] 3 6 /2 [ 4 / 416] 3 /40 [ 4 / 88] 1 /55 [ 5 / 921] 2 10 /4 [ 7 / 408] 5 /0 [ 7 / 17] 2 /05 [ 7 / 831] 1 12 /0 [ 8 / 547] 5 /2 [ 7 / 60] 2 /25 [ 8 / 594] [m/s] 2 [m] 4 /4 1 / /1 0 / /9 0 / /15 /

6 20. (4/0) [10] / (10/0) 30 (13/9) ( 3/1 ) 0/ ( 3/1 ) 0/ /15 / 80

7 ( 3/1 ) 0/ / /81 [ 9/772] 6 /90 [ 10 / 04] 1 /18 [ 1 / 693] [psi] 3 8 /22 [ 11 / 795] 3 /40 [ 4 / 88] 1 /62 [ 2 / 325] [ ] 2 8 /82 [ 12 / 656] 5 /0 [ 7 / 17] 1 /78 [ 2 / 554] [7]. 13.[31]. 9 /67 [ 13 / 876] 5 /2 [ 7 / 60] 2 /82 [ 4 / 046] [m/s] 3 3 / / / ().. (2) = (2)... Z (1) /15 /

8 Z ) ( :... Z Z / / Z.. 1/6 0/ /15 / 82

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