Simulation of the Effects of an Air Blast Wave - ELSA - Europa

More documents

Recommendations

Info

Figure 32: Modelling of the spherical model – number of elements in the different modelsCase Size of the modelnel0/nel1/nel2Length[m]Distance withaspect ratio = 10Number ofelementsSPHE1 10/10/10 1 (5.55) 1625SPHE2 10/20/70 1 0.79 6875SPHE3 10/20/90 1 0.62 8375SPHE4 10/20/150 1 0.37 12875SPHE5 10/20/200 1 0.28 16625SPHE6 10/40/200 1 0.28 18125SPHE7 20/40/200 1 0.56 73000SPHE8 10/10/70 2 1.70 6125SPHE9 20/20/140 2 1.70 12125Table 7: Calculations with spherical chargesSPHE1In this calculation a small model with a coarse mesh is used. The results show a relatively lowmaximum pressure (See Figure 33).44
Figure 33: Maximum pressures versus distance – spherical modelsSPHE2, SPHE3, SHPE4 and SPHE5These calculations use finer meshes. The maximum pressures are increasing. The models SPE2 andSPE4 give realistic results. The models SPHE4 and SPHE5 give larger maximum pressure than theexperimental values. An Eulerian calculation should normally result in smaller values than theexperimental values (in contrast to a Lagrangian calculation which reacts stiffer with smallerelement sizes).SPHE6The larger values for the maximum pressure in model SPHE5 start near the charge. Therefore, themodel SPHE6 tests if a smaller element size in the outer charge (See d) red range) can result inmore realistic values.The overestimating of the pressure begins in this model earlier than in the model SPHE5. The sizeof the elements in the explosive should not be the reason for the overestimation.SPHE7This calculation uses a finer mesh in the inner charge (See Figure 31 d) green range). With thesmaller elements in the inner charge also the number of the elements in tangential direction isincreased.The results are quite better. For every model with small elements there is a limit from which the cal-45
Page 1 and 2: Simulation of the Effectsof an Air
Page 3 and 4: Distribution ListLechner S.Anthoine
Page 5 and 6: 1 IntroductionThis work is being co
Page 7 and 8: • Far zone. The blast wave result
Page 9 and 10: Figure 2: Model of Kingery [14] wit
Page 11 and 12: 2.2.3 ImpulseThe impulse of the air
Page 13 and 14: Figure 5: Different parameters for
Page 15 and 16: 250200Impulse from KingeryImpulse w
Page 17 and 18: the specific heat ratio and the spe
Page 19 and 20: determined with a fluid pre-calcula
Page 21 and 22: From this asymptotic form it can al
Page 23 and 24: 2.0E+101.6E+10without burn mass fra
Page 25 and 26: Case opening d pyra d ex,in d ex,en
Page 27 and 28: Pressure [Pa]2.4E+102.0E+101.6E+101
Page 29 and 30: 5.0E+094.0E+09EUROPLEXUS x=0.105EUR
Page 31 and 32: Cased pyr /d ex,in /d ex,end /d air
Page 33 and 34: Figure 21: Comparison of a coarse w
Page 35 and 36: CON9This model has approximately th
Page 37 and 38: 4E+7Max. pressure [Pa]3E+72E+7Kinge
Page 39 and 40: Case Size of the model Description
Page 41 and 42: CUB4This model uses a finer mesh th
Page 43: 6. Complete the volumes by adding t
Page 47 and 48: experimental values is obtained wit
Page 49 and 50: 4.6.3 Arrival TimeThe arrival time
Page 51 and 52: value in [13]). These results show
Page 53 and 54: Modell airl bBubbleBubbleBubbleTNT
Page 55 and 56: Several calculations are done with
Page 57 and 58: 3. Calculation of the factor α bub
Page 59 and 60: quadratic. Therefore, the size of t
Page 61 and 62: 400Impulse [Pa sec]300200.Kingery 5
Page 63 and 64: 5 = hemispherical detonation (half
Page 65 and 66: 9 References[1] Alia, A.; Souli, M.
Page 67 and 68: 10 Apendix10.1 EUROPLEXUS Codedyms.
Page 69 and 70: CALLMECVAL(GET_FMT(6),NEWMAT%MATVAL
Page 71 and 72: 10.2 Miscellaneous codeairblastresu
Page 73 and 74: else{ //Kingerydouble t=log10(z);do
Page 75 and 76: maxar=0;REPE I0 (NBEL vges);ar = as
Page 77 and 78: *defining the surfaces around the a
Page 79 and 80: lpyr1 = p1 d ppy2;lpyr2 = p1 d ppy3
Page 81 and 82: lpyr2 = p1 d ppy3;lpyr3 = p1 d ppy4
Page 83: *Cube intermediaire (centre=o0 et a
Page 86: The mission of the JRC is to provid

Simulation of the Effects of an Air Blast Wave - ELSA - Europa

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?