Laserfiche WebLink
TW <br /> International Journal for Research in Engineering Application&Mana ement JREAM <br /> ISSN:2454-9150 <br /> Experimental Results- :30 <br /> Sound waves significantly affect the fire extinguishing 25 <br /> process. To evaluate the results, fire was exposed to 26 <br /> various sound frequencies: OHz, 10Hz, 30Hz, 35Hz and <br /> 40 Hz. Variation of pressure, sound and acoustic a, 24 <br /> velocity were evaluated with respect to the above <br /> chosen frequencies.Sound travels in the form of waves, <br /> which are simply variations of pressure in a medium. 2tj <br /> The energy from vibrating objects, such as speaker <br /> membranes, moves from particle to particle in the air <br /> in a repeating pattern of high and low pressure zones lt' <br /> that is perceived as sound. It is found that the effective 14 <br /> range was between 30 Hz and 40 Hz,within the range <br /> of human hearing. The effect of variation of pressure 1' <br /> with frequency is shown in Graph.1.0.916 1t] 15 "�� 2r' 30 3' � I5 <br /> Frequency (Hz) <br /> tl,tJ-'1 71 <br /> 41.444 Graph.3Variation of Acoustic Velocity with Frequency <br /> (1.1113 <br /> tl'{� The research has also revealed the effects of important <br /> 1.1.147 parameters such as the length to diameter ratio of the <br /> vortex tube on the acoustic velocity and pressure of <br /> L II'{13R waves which has also been used in this <br /> 31- experiment.Experimentally,the geometry of the vortex <br /> tube was optimized considering important parameters. <br /> The chosen variations were 100 to 400 mm for length <br /> U.°135 and 50 to 100 mm for diameter. It was found that the <br /> 0 5 10 15 20 25 30 35 40 4' length of 300 mm and diameter of 100 mm show the <br /> Frequency(Hx) optimum pressure, velocity and sound for <br /> extinguishing fires. <br /> The effect of geometry of the vortex tube on the <br /> Graph.lVariation of Pressure with Frequency pressure has been illustrated by Graph.4. <br /> The effect of variation of decibels of sound with the <br /> o.94(-) <br /> frequency is shown in Gra h.2. 11.94 <br /> q Y p <br /> L '+/ <br /> t}(J L 11,'111 <br /> °� Hf1 11 ill j11111.riU1UUZii]:�tHJ:�!"�I.M-}�Ptl-}rii] <br /> a Ire length(mni) <br /> 70 50 I171t1 cll:r - 1Ut1 flue ilia <br /> it <br /> 40 Graph.4Effect of Vortex Geometry on Pressure <br /> 6 1Q 1S "10 2; .30 .3; 40 4! <br /> The effect of geometry of the vortex tube on the <br /> Frequency (H2) acoustic velocity has been illustrated by Graph.5. <br /> Graph.2Variation of Sound with Frequency <br /> The effect of variation of acoustic velocity with the <br /> frequency is shown in Graph.3. <br /> 241 AMET_0006 @ MIT College of Engineering,Pune,Vol.04,Special Issue AMET-2018 DOI:10.18231/2454-9150.2018.1391 <br />