粉尘处理设备爆破片面积计算程序

Pmax = 0.2Pred (A0.1)( V0.18) 0.032 0.47 psi 4.3 (1 Vent) r (m) Pr (bar) 7.3 0.019 10.3 0.014 13.3 0.010 16.3 0.009 psig 0.28 0.20 0.15 0.12
Dist to Max Press Rs = 0.2Lf (horizontally)
Pr = Pmaxa(Rs/ r)
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Effect of Vent Duct P'red,max/Pred,max = 1 + 17.3(A/V
0.753
Length Ld = ) Ld/Dd P'red,max/Pred,max =
3 5.0
Dd =
0.7
Ls =
8.4
P'red,max = reduced explosion pressure with duct
1. NFPA 68, Guide for Venting of Deflagrations , 2002 Edition, National Fire Prevention Association, 1 Battery Park, P.O. Box 9101, Quincy, MA. 02269-9109. 2. Crowhurst, D., Colwell, S., Hoare, D., Benselium, M., Schramm, S., Friehmelt, V., Guidelines for Industry: Dust Explosions - Flame and Pressure Effects Outside Vents , Dust Explosions, London, IBC, October 1995.
INPUT 输入数据 设备名称 单元号 设备参数 容积'Vol (m )= 最大承压'Pred (bar)= 粉尘性质 名称
3
备注 Vessel ID: 10 0.115 长径比L/D= 防爆启动压力'Pstat (bar)= 备注 KSt, bar-m/sec Pmax(bar) RESULTS 计算结果 所需泄爆面积Vent Area (M2) = External Effects 喷射火焰长度Flame Jet Length: 0.36 1 Vent 2 Vents* Fireball Vol Fireball Width Pmax, External Distance to Pmax 单个泄放口 2个泄放口 火球体积 火球宽度 外部最大压力 最大压力区 m2 80 7.6 MIE = MIT, C = 3-5 mJ 510 2 0.10 Existing FECTS Flame Jet Length, M 1 Vent, Lf = 10V0.3 = 2 Vents*, Lf=6V = *well separated vents Fireball Size Fireball Vol = Fireball Width =
0.3
Max. Ext. Press. 22 13 Vf = 10V 100 m3 5m Pmax, bar = Rs (m) =
21.53 m 12.92 m 100.00 m3 4.63 m 0.03 4.31 bar m
燃爆火球大小FireBall
外部形成的最大爆炸压力
Vent Size Equation - NFPA 2002 for L/D <2: Av = (8.535 x 10-5) (1+1.75Pstat) Kst V0.75 [(1-P)/(P)]0.5 Where P = Pred/Pmax A = Incremental Area for L/D > 2 DA = 0.00 m2 Atotal = 0.36 m2 DA = 1.56 Av[1/Pred - 1/Pmax]0.65log(L/D - 1) 0.36 m2