NPO Poisk

High pressure cylinders made of composite materials for storage of ECG gaseous components for deep research apparatus


High pressure cylinders made of composite materials for storage of ECG gaseous components for deep research apparatus.



Y.A. Bogenov, A.S. Gadalin (St. Petersburg SMTU) O.S. Kluynin (POISK Ltd. St. Petersburg)



Composite cylinders on liners base of chromium-nickel austenitic steels and aluminum alloys with plastic winding of roving Armos or Ruslan-BM-650 can stand an inner pressure of different gases to 120MPa according to thickness and type of rovings winding. However, they do not work well under the outer pressure, allowing the maximum outer pressure 5-10 MPa. In terms of quantity could be considered the using of such cylinders for storage gaseous reactants by the pressure drop operation, safe the residual pressure of cylinder 2, compensating outer hydrostatic pressure (no less than 50 MPa). In this case there is no need for strong corps AUSA (Autonomous Uninhabited Submersible Apparatus) for accommodate of storage reagent systems using on air space. Pressure regulator and water for reaction can be placed in a strong corps of fuel cell elements system and in automation system (pic. 3.3.12), which size can be degreasing in compare with 1st and 2nd variants. On the structured scheme is marked maximum degrease of inner pressure of technologies which are developed. It is the real opportunity to increase the pressure up 120 MPa which accepts for the further calculations.



Picture 3.3.12 the structured scheme of placement ECG systems in AUSA at gas-compressor storage of reagents in composite cylinders in seawater.



The gas volume V at max pressure 1 which need for mass flow rate can be determined from the equation


V· ρ(1) – V ·ρ(2) = ,


where ρ(1) ρ(2) - the real gas density at initial pressure 1 and at final pressure 2, defined by the equation of van der Waals. It shows


V = /[ρ(1) – ρ(2)]


that the hydrogen cylinders are critical in there volume. For 1 = 120MPa ρ2 = 0,043kg/dm3. For 2 =50 MPa ρ2 = 0,028 kg/dm3. In setting with power = 1800W for = 10 kg require the hydrogen capacity V 2 = 670 dm3. In setting with power = 3200W the hydrogen storage capacity will be V 2 = 1670 dm3. Research and Production Association POISK Ltd. (St. Petersburg) produces the composite cylinders BD-40 for hydrogen transportation under the pressure 40 MPa with capacity from 1000 till 2500 l (pic. 3.3.13 and 3.3.14) with assurance factor = 2.6 [1].



A big mass and dimensions of cylinder which minimize capacity 1000 l: weight = 900; length L =1900 mm; outside diameter D = 1134 mm do not allow to place it in a limited displacement AUSA. It takes moreover the increase of wall thickness on the pressure 120 MPa.



Pic. 3.3.14 Metal-plastic cylinder BD-40 for nitrogens storage and transportation with capacity 2500 l.



Cylinders liner BD-40 with diagnostic elements The winding of pressure cylinders shell BD-40



To realize the required volume nitrogen storage, parameters of strength and mass of cylinders in AUSA, calculations are made for cylinders with lower capacity based on steel liners with diameter 290 mm. The safety factor is reduced to = 2,4. The thickness of the reinforced wall is 54 mm. The outside diameter of cylinder is 400 mm. The main parameters of cylinders for accommodation of 670 l hydrogen at pressure 120 MPa are given 3.3.11.



Table 3.3.11 Parameter of metal-plastic cylinders at calculated pressure = 288 MPa and mass of hydrogen consumed 2 = 10 kg


Cylinders Weight of liner, kg Weight of plastic, kg Weight of cylinder, kg Length of cylinder, mm Water displacement, dm3 Weight of all cylinders, kg Water displacement of all cylinders
8 to 85 dm3 10 108 118 1365 150 944 1200
6 to 114 dm3 13 144 157 1810 200 942 1200
4 to 172 dm3 20 215 215 2700 308 860 1232



Serial produced petal-plastic (composite) cylinders with high pressure




Cylinders for hydrogen and oxygen with capacity from 80 till 160 dm3 at working pressure 44 MPa.




Composite cylinders for hydrogen and oxygen with capacity from 20 till 80 l, operating pressure 41 MPa




Metal-plastic cylinder BMA-40 for nitrogen, oxygen and helium capacity from 100 l, operating pressure 40 MPa.


29.03.2012 23:12