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Abstract: High-pressure water mist system is a new type of
fire-fighting unit using water hydraulic technology. The advantages of
water mist include environmentally friendly, fast and effective fire
suppression, minimum quantity of water requirements, low water losses.
It has been in fact widely expected the most potential substitute of
Halon fire-fighting system. The inner flow state of the vital execute
component—direct jet atomizer is analyzed by using axial symmetrical
boundary momentum integral method. The atomizer shape dimension’s
influence on two inner flow parameters, boundary layer thickness δ,
accelerate factor K is assessed. Besides, the outer atomization
characteristics related to fire-fighting performance, for instance,
outlet velocity, Sauter Mean Diameter (SMD) is analyzed. Simulation
results are experimentally verified. The results show that the system
working pressure is the most important factor to these outer atomization
characteristics and 8~9 MPa is the appropriate area of stable
atomization pressure for this prototype of direct jet atomizer. The
atomizer shape dimensions include contract angle a, length of atomizer
neck l/d has influence on inner flow parameters and outer atomizer
characteristics, but not distinct. The optimum atomizer inner structure
is selected.
Key words: Water mist Fire-fighting Jet atomizer Atomization
characteristics
CLC No: TH137
国家自然科学基金
(5005019)和浙江省青年人基金 (RC99040) 资助项目. Received 20020123, received in
revised form 20020428
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