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APLIKASI BERNOULLI PADA Saluran Kovergen/Divergen Diffuser, Sudden expansion Fluida gas Flowmeter : Pitot tube, Orificemeter, Venturimeter, Rotameter. PERS.BERNOULLI. Steady. PERS.BERNOULLI. HEAD FORM OF BERNOULLI EQUATION. DIFFUSER. Cara untuk untuk memperlambat kecepatan aliran. 2.
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APLIKASI BERNOULLI PADA Saluran Kovergen/Divergen Diffuser, Sudden expansion Fluida gas Flowmeter : Pitot tube, Orificemeter, Venturimeter, Rotameter
PERS.BERNOULLI Steady
PERS.BERNOULLI HEAD FORM OF BERNOULLI EQUATION
DIFFUSER Cara untuk untuk memperlambat kecepatan aliran 2 1 z1-z2 V1,P1,A1 V2,P2,A2
1 2 P1,V1 P2,V2=0 z1-z2 SUDDEN EXPANSIONS Cara untuk untuk memperlambat kecepatan aliran
BERNOULLI UNTUK GAS Patmosfir 1 VR,PR P1,V1 -------------------- P1-Patm V (ft/s) Psia (Eq.5.17) -------------------------- 0.001 35 0.1 111 0.3 191 0.6 267 1.0 340 2.0 467 5.0 679 ------------- V(ft/s) (Eq.in Chap.8) --------- 35 111 191 269 344 477 714 (Eq.5.17) Eq.in Chap.8
h1 h2 2 1 BERNOULLI FOR FLUID FLOW MEASUREMENT • • PITOT TUBE
VENTURIMETER 1 2 V2,P2 V1,P1 Manometer
D Flow d Venturi Flowmeter The classical Venturi tube (also known as the Herschel Venturi tube) is used to determine flowrate through a pipe. Differential pressure is the pressure difference between the pressure measured at D and at d
ORIFICEMETER 1 2 Orifice plate Circular drilled hole where, Co - Orifice coefficient - Ratio of CS areas of upstream to that of down stream Pa-Pb - Pressure gradient across the orifice meter - Density of fluid
ORIFICEMETER where, Co - Orifice coefficient - Ratio of CS areas of upstream to that of down stream Pa-Pb - Pressure gradient across the orifice meter - Density of fluid
compressible flow through an orifice Y is 1.0 for incompressible fluids and it can be calculated for compressible gases.[2] For values of β less than 0.25, β4 approaches 0 and the last bracketed term in the above equation approaches 1. Thus, for the large majority of orifice plate installations:
P1 P2 D d 1 0.95 0.9 0.85 Cd 0.8 0.75 0.7 0.65 0.6 102 105 106 107 Re Sudden Contraction (Orifice Flowmeter) Orifice flowmeters are used to determine a liquid or gas flowrate by measuring the differential pressure P1-P2 across the orifice plate Flow 103 104 Reynolds number based on orifice diameter Red
ROTAMETER Tansparent tapered tube with diameter D0+Bz Solid ball with diameter D0 Density B 3 2 2 1 z=0 Fluid with density F
ROTAMETER D0+Bz Solid ball D0 Density B 3 2 2 1 F z=0 Only one possible value that keep the ball steaduly suspended
ROTAMETER D0+Bz For any rate the ball must move to that elevation in the tapered tube where Solid ball D0 Density B 3 2 2 1 F z=0 The height z at which the ball stands, is linearly proportional to the volumetric flowrate Q
TEKANAN ABSOLUT NEGATIF ? 2 40ft 1 10ft Applying the equation between point 1 and 3 3 Applying the equation between point 1 and 2 ? negatif This flow is physically impossible. It is unreal Because the siphone can never lift water more than 34 ft (10.4 m) above the water surface It will not flow at all