The design object is a vehicle factory assembly workshop and petrol filling station located in Jiangxia District in the city of , the new workshop section covers an area of 65771 square meters, with a total construction area of 69302 square meters, building layers one layer, the construction height of 1.245 meters (outdoor ground to roof parapet high degree), indoor surface design elevation +0.000 quite to the absolute elevation 22.300 meters.

In General layout design. Determine the fire risk grade of the workshop is the 4th. The whole workshop is separate for smoke prevention and fire prevention. The fire resistance limit of each part is column (2.5h), beam (1.5h), roof bearing member (1h). The safety distance is in conformity with the specification, and the ring fire lane is set according to the specification.

Safety evacuation to verify the workshop evacuation door width meets the requirements of the specification. And the fire resistance limit of the decoration materials in the workshop and the material contents are determined. Shop decoration materials burning performance rating is roof (B1); walls (B2); ground (B2); partition (B2).

In the design part of the fire extinguisher, the fire risk grade of the workshop and the gasoline filling station are respectively the light danger and the serious danger level. Fire types are class a fire and class AB fire. The whole workshop set up 140 fire extinguishers point each point 3 with MF/ABC3 ammonium phosphate dry powder fire extinguisher, gasoline filling station set up 3 fire extinguishers point each point 1 with MF/ABC5 ammonium phosphate dry powder fire extinguisher.

In the fire hydrant system design, first determine the workshop water hydrant is 10L/s. The calculated fire hydrant protection radius is 29.23m, and determine the layout and arrangement of fire extinguishing recloser, with a fire hydrant box. The design water quantity is 12.16L/s, the total head loss is 0.063635MPa. Pump type selection for type IH80-50-250A single - stage single - suction centrifugal fire pump two units, one with a. The design parameters are: flow 15.61L/s; head 70m; speed 2980r/min; efficiency 57%.

For automatic sprinkler system, the area is designed to be a serious hazard. Design water spray intensity as m2, 24.4L/min, design area of 279m2, nozzle working pressure 0.1MPa. Nozzle selection model for the rapid response of the VK520 early suppression of vertical sprinkler, action temperature 74 degrees, the flow coefficient K=200. The design water quantity is 131.7L/s. Total head loss was 0.03MPa. Pump type selection for type 10SH-13 single stage double suction in the open pump two sets, one with a. The design parameters are: flow 134.7L/s; head 24m; speed 1450r/min; efficiency 86%.

The protection level of each area is one level, and the centralized alarm system is adopted. The main types of detectors are combustible gas detector, temperature detector and smoke detector. Gasoline filling station installation temperature detector and combustible gas detector, and the rest room installation smoke detector. Combustible gas detector alarm is pided into two times, one or two times the setting value should be less than equal to 25% of the explosion limit and 50% of the explosion limit. Temperature is 74 degrees Celsius, the temperature of the nozzle is consistent with the starting temperature of the nozzle. Each set fire hydrant manual alarm device and alarm device.

The smoke exhaust system is mainly composed of natural smoke exhaust and mechanical smoke exhaust. In the roof set 666 area of soluble 4.5m2 with lighting, as natural ventilation. Two mechanical exhaust outlets are arranged on the two narrow side of the gasoline filling station steel platform.

The simulation results were obtained for pure gasoline combustion, open spray case and car combustion under the condition of auto combustion and no spray. The simulation results were obtained for pure gasoline combustion, open spray case and car combustion under the condition of auto combustion and no spray. Through comparison, to determine the reliability of the spray system and smoke settings.