Theory Design Air Cushion Craft 2009 Part 3 pptx

... A /J J Air cushion wave-making drag 95 10 20 30 40 50 60 70 80 90 Fig. 3. 12(b) Wave-making drag coefficient for yawed craft, F r = 1.0. 10 20 30 40 50 60 70 80 90 Fig. 3. 12(c) ... (0.07656 Ib/ft 3 /32 .17 = 0.00 238 slug/ft 3 in imperial units) D c = nozzle discharge coefficient (2 .3. 4 item 5), D c = 0. 53 for 45° segment, L = peripheral leng...

Ngày tải lên: 11/08/2014, 18:20

... 45 1.9 SES and ACV design 46 2. Air cushion theory 48 2.1 Introduction 48 2.2 Early air cushion theory developments 50 2 .3 Practical formulae for predicting air cushion performance ... damping coefficients 76 3. Steady drag forces 84 3. 1 Introduction 84 3. 2 Classification of drag components 84 3. 3 Air cushion wave-making drag (/? w ) 8...

Ngày tải lên: 11/08/2014, 18:20

... [2p c /pJ 0.5 (3. 51) Drag Fig. 3. 35 Three operation modes of an ACV over ground terrain. Effect of various factors on drag 133 234 5 v(m/s) Fig. 3. 48 Influence of cushion length/beam ... (/B, = 2.14, A/( = 11.96, C 3 = 0.6, a" = 0.5° 600 - 500 - 400 - 30 0 - 200 - 100 - Las fig 3. 31 2. as fig 3. 31 40 60 v^km/h) 80 100 Fig. 3. 32 Comparison...

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... at bow T bl Units km/h N/m 2 mVs m m m m 30 .67 2690 23. 65 0.402 0. 038 9 0.1 535 0.1 535 42.90 2716 23. 55 0 .38 6 0. 039 9 0. 138 5 0. 138 5 51.08 27 63 23. 38 0 .35 6 0.0517 0.111 0.111 Table 4.6 The calculation ... width W 4 fi c lJB e PA PC Q KG Z b,s a ft 5, t m m kgf/m N/m 2 m m deg deg m 13. 7 13. 2 3. 5 3. 77 19. 93 2 630 0.00757 1.27 0.15 60 89 0.12 15.95 15.2 3. 5...

Ngày tải lên: 11/08/2014, 18:20

... to air cushion and skirt F c = jetted thrust due to air leakage from cushion during turning manoeuvre F m = air momentum force z m = distance from ground to the centre of air ... of the craft must be equal to zero. 3. The inflow and total air pressure of fans must satisfy the air duct characteristic curve and the hovering characteristics of t...

Ngày tải lên: 11/08/2014, 18:20

... 255 _ . 2 /3 + 1 /3 r b /r c Three-dimensional 1 [ 1 Two-dimensional _ f 1/2+1/2 r E /r c Three-dimensional 2 [1 Two-dimensional _ [ 1 /3 + 2 /3 r E /r c Three-dimensional 3 [ 1 Two-dimensional _ ... the cushion pres- sure acting on the stern skirt is uniformly distributed, may not be accurate, particu- larly in the case where craft are running on a wate...

Ngày tải lên: 11/08/2014, 18:20

... follows: D = a n a 23 - a 2 i a l3 D l = a ls - a n * 3 - a l4 x 5 D 2 = a 25 - a 22 x 3 - a 24 x 5 then x { = 1 x 2 = x 3 x 3 = (a 23 Z), - « 13 D 2 )/D x s = O H ... pressure is assumed and the cushion plane is simplified as a rectangle. 3. Changes of air density and cushion pressure in the plenum chamber (air cushion) are c...

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... wave height h l /3 = 0.45 m, i.e. h l /3 /W°' 33 > 0 .3, where PFis the displacement of the craft (m 3 ). Sometimes, the plough-in phenomenon even happened to craft running ... ACV/SES 33 1 Significant wave height (ft) 14 12 10 10 30 40 50 Craft speed Fig. 8 .32 Comparison of ship speeds between SR.N4 Mk3 and Mk1 in head seas and beam...

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... passenger cabin Bridge/wheelhouse 94 96 93 92 83. 5 83 86.5 80.5 93 94 75 83 80 89 85 80 73 65 Scaling criteria for hovercraft models 34 7 Table 9 .3 The elastic modulus E and coefficient ... of cushion air compression is too small to change the air flow rate and fluctuate the cushion pressure. This is not true for full-scale craft, especially fo...

Ngày tải lên: 11/08/2014, 18:20

... 11.95 58.29 18 .38 35 70 29.80 0.0067 HM.218 UK SES 14 .39 70.19 27 .30 33 90 21.50 0.00412 HM.221 UK SES 17.44 85.07 37 .20 33 39 26.80 0.00427 7 13 China SES 17.5 87 .30 28.00 32 00 50.00 0.008 711-IIA ... pressure chamber (on craft SR.N4, BH.7) 0. 037 0. 037 0. 035 0. 035 0. 033 0. 033 Mixed controlled and free diffusion (on craft SR.N6) 0.0114 0.0110 0.0105 Cent...

Ngày tải lên: 11/08/2014, 18:20