To study the relationship between the friction loss and flow rate for compressed fluid flow and estimate the value of friction coefficient (f).To study the relationship between friction coefficient and Reynolds number in a straight pipe.Determine the friction coefficient for compressed fluid flow in straight pipe.Determine the value of specific heat ratio () for air.To study the relationship between fluid flow rate and pressure drop (head loss) along the pipe elbow.

Dry air is flowed through pipes to the compressor in a variety of flow conditions that can be measured, by using a straight pipe and elbow pipe. While nozzle is used to determining the value of .

In contrast to solids which tend to maintain their shape under certain disorders, the fluid is a substance that can not withstand permanent deformation. At a certain temperature and pressure conditions, each fluid having a specific density. Although the density of the fluid depends on temperature and pressure, density changes due to changes in these variables may be large and probably too small.

If the density is only slightly affected by changes in temperature and pressure are rather large, then the fluid is called uncompressed fluid (incompressible). But if the density is sensitive to changes in temperature and pressure, the fluid is called a compressed fluid (compressible).

Liquid fluid is not usually considered to be compressed while gases including compressed fluid. However, the density of the liquid can undergo significant change if the pressure and temperature are changed in a fairly broad range.

SIMPLE PIPE FRICTIONThe equation for friction loss :These equation can be

With plotting P3 against (P4) well obtain linear graphic with slope

Therefore we can obtain f based on the slope

FRICTION COEFFICIENT VARIATION WITH REYNOLDS NUMBERSThe equation to determine f :With (Pmid-Poutlet) denoted with -P4 and (Patmos-Pinlet) denoted with P3.Nikuradse-Von Karman equation

FRICTION COEFFICIENT VARIATION WITH REYNOLDS NUMBERSBlasius equation f = 0,079 Re-1/4Then plot log f against log Re and plot log 1/f against log (Ref) so we can obtain the correlation between friction coefficient and Reynolds number

FRICTION COEFFICIENT FOR COMPRESSED FLOWWith k = 0,9, the equation to determine f :

Then plot VS

From the slope, 4fl/d, we can obtain the value of f

PRESSURE-FLOW CHARACTERISTICS IN A CONVERGENT-DIVERGENT DUCTEquation used :

With P1 = Patm Pthroat then we plot kP1/Patm against with as

slope.

DETERMINATION OF SPECIFIC HEAT RATIO VALUEThe specific heat reaction () can be obtained with this equation :

Then plot kPinlet/Pthroat vs Pthroat/Patm with as slope

PRESSURE DROP ALONG 90O BENTThe correlation between hL (head loss) and fluid velocity can be written in mathematic equation : hL = klong (v2/2g)With hL = (Pexit Pentry)/gThen subtitue 2 equations above : klong = 2 (Pexit Pentry) /v2Plot v against hL and v against klong.

Simple pipe friction: 15 variations of rotary compressor speed.Variation of friction factor - Reynolds Numbers: 15 variations of rotary compressor speed.The flow of compressed Friction factor: 15 variations of rotary compressor speed.Determination of -Air : 15 variations of rotary compressor speed.Pressure drop in 90o bent : 15 variations in inlet pressure.

Armfield C1-MkII Compressible Flow Bench

Straight Pipe 19ID

Elbow Pipe 90o

Nozzle

Pressure drop relationship in Straight Pipe ID = 19 mm

Friction Factor Reynolds Number with Blausius Equation

Friction Factor-Reynolds Number withNikuradsee-von Karman Equation

Friction Coefficient for Compressible Flow

Determination of Gamma Factor

Quadratic Flow rate influence on Elbow Pipe Head Loss

Graph klong vs Flow Rate (V)

SIMPLE PIPE f = 0,01142. The greater the friction, the pressure drop also increases.Friction coefficient increases with increasing Reynolds Number, friction values not only depend on Reynolds Number but also depends on pipes surface roughness.Compressible flows friction factor is greater than incompressible flow due to gamma factor in compressible flow

For compressible flow, f = 0,01923 and for incompressible flow, f = 0,01142.Gamma value obtained 6,17479 whereas the theoretical value is 1,4.A decrease in pressure in flow through a elbow pipe where the pressure drop can be expressed in headloss. Headloss of elbow pipe is directly propotional to the quadratic of flow rate. In this experiment a constant headloss in elbow pipe in the range 3,9 83.

The supersonic nozzle is a new apparatus which can be used to condense and separate water and heavy hydrocarbons from natural gas.The swirling separation of natural gas in the convergent-divergent nozzle was numerically simulated based on a new design which incorporates a central body.

Axial distribution of the main parameters of gas flow was investigated, while the basic parameters of gas flow were obtained as functions of radius at the nozzle exit.The effect of the nozzle geometry on the swirling separation was analyzed.

The numerical results show that water and heavy hydrocarbons can be condensed and separated from natural gas under the combined effect of the low temperature (80C) and the centrifugal field (482,400g, g is the acceleration of gravity).The gas dynamic parameters are uniformly distributed correspondingly in the radial central region of the channel.

High gradients of gas dynamic parameters near the channel walls may impair the process of separation.The geometry of the nozzle has a great influence on the separation performance.Increasing the nozzle convergent angle can improve the separation efficiency.

The swirling natural gas can be well separated when the divergent angle takes values from 4 to 12 in the convergent-divergent nozzle.

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