Fire Engineering Assignment

Added on - 21 Apr 2020

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Fire Engineering1AssignmentNameInstitution Affiliation
Fire Engineering2Question 1a)Mass burning rate is the mass loss per unit of the burning material within specific condition.But,M`` = 1.27× 106 ῥl (ΔHcΔHv) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ( i)Where; ῥl is the density of fuel at boiling point,ΔHcis the heat of combustion andΔHvis themodified heat of combustion and M`` is the mass burning rate densityAlso,ΔHvis given byΔHc+TaTbCpdTThe density of keroseneῥl is 0.0008kg/m3And heat of combustion of kerosene= 418kJ/moleModified heat of combustion of kerosene is given by 178kJ/moleTherefore M`` = 1.27× 106 ῥl (ΔHcΔHv)= 0.010106 (418178)Thus, 0.0237kgs-1m-2b.Heat release rateHeat rate = Ws ×C×ΔT ................................................................................... (ii)
Fire Engineering3Where Rh is the heat rate in btu/hrWs is steam flow in btu/hrC is the specific heat capacityAnd ΔT is the change in temperature in0FBut the heat capacity is given by 0.48btu/1b0FHence Rh is 0.48Wsc.Radiative fraction is heat produced during combustion and is distributed to the surroundingmainly the radiation and the convection. The most significant parameters of radiation is thefraction of the heat produced from the fire.q= δT4A . . . . . . . . . . . . .............................................................................. (iii)Where, q is the radiative fraction, δ is 5.6703 ×108(W/m2k4), T is the absolute temperature in Kand A is the area of the body.T^4 this is the absolute temperature near the surface of the flame that is dependent.q= 5.6703 ×108×T4×Πr2q= 5.6703 ×108×T4×3.142 ×2.52= 1.1135× 1010T4mC/kg.d.What is the necessary separation of the tanks
Fire Engineering4To avoid wastage as when more than one tank catches fire the other do not hence nowastages. This can also lead to the contamination of the fuel in the other tank.To reduce more accident as when more than one tank catches fire more accident can be seen.And the formula between these two burning tanks can be obtained by the following formula;D= (δT4×Πr2) / (ρ1V1 +ρ2V2 )Where ρ1 is the density of the kerosene in tank 1 and ρ2 is the density of kerosene in tank 2,V1 is the volume in tank 1 and V2 is the volume in tank 2 and D is the distance between thetanks.Question twoThe neutral plane can be used in the determination of the on what area the fire islocated. Below the neutral plane the air is drawn into the structural and then above the planethe exhaust gases from combustion are removed. The identification of the plane is made oncethe opening is done. This identification aids in the indication of the location of fire. When thefire is detected in particular area in the first floor, the opening of door at the front is done thatwill allow the smock to come out of the floor from the top part whereas the fresh air will beallowed to come in from the lower part of the floor. This process is where the opening is thevent and is created with regards to the fire in the room but in case where the location of fire isat the basement there will be creation of the opening in any area of the surface hence leading tothe removal of the smock in any direction thus the flow is unidirectional.But is the making of the opening is done under the neutral plane then the smock thatflows out from the new vent might not be seen, hence the heat amount that flows is higher but
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