# Pressure drop through volumes of compressible fluid

• Natalinop
In summary, the conversation discusses estimating pressure in a cavity, specifically P2, and calculating pressure drop across an annulus with known areas A1 and A2. The speaker also mentions assumptions and calculations for velocity and flow rate. Friction losses at the exit pipe are also mentioned, with a formula provided for calculating the pressure drop. However, the speaker is unsure how to calculate losses at the entry and exit of the pipe due to unknown volumes involved.
Natalinop
Homework Statement
Pressure drop through volumes of compressible fluid
Relevant Equations
deltaP = 1/2 (density)velocity^2)
I'm trying to estimate the pressure in the cavity, i.e. P2. I know the areas, A1 which in practicality is an annulus and A2 which is a 600m pipe with i/d 8mm.
I would like to initially understand how to calculate the pressure drop across the annulus.

At the moment I'm assuming the pressure drop which is not useful...
ΔP (P1-P2) = 2 kPa
v1 = SQRT(2000*2/1.2)= 57 m/s

Q1 (flowrate) = v1 * 26 = 1482 m2.mm/s

v2 = Q1/A2 = 1482/46 = 32 m/s

Friction losses at exit pipe
Fluid exits container at pipe length of 600mm length (L) and 8mm inner diameter (d)
L/d = 75
f = 0.05

ΔP (P2-P3) = 0.5*1.2*322*75*0.05= 2.3 kPa
NOt quiet sure how to calculate losses at entry and exit of pipe.

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What are the volumes involved?

## What is pressure drop?

Pressure drop refers to the decrease in pressure that occurs as a fluid flows through a volume. It is a result of friction and other forces acting on the fluid as it moves through a system.

## How is pressure drop calculated?

Pressure drop can be calculated using the Bernoulli's equation, which takes into account the fluid velocity, density, and the height difference between the two points in the system. Other factors such as fluid viscosity and pipe roughness may also affect the pressure drop.

## What factors affect pressure drop?

Several factors can affect the pressure drop through a volume of compressible fluid, including the fluid properties (density, viscosity), the flow velocity, the length and diameter of the system, and the roughness of the pipes or surfaces through which the fluid is flowing.

## How does pressure drop impact system performance?

Pressure drop can have a significant impact on the performance of a system. High pressure drop can result in decreased flow rates, reduced efficiency, and increased energy consumption. It can also cause damage to the system components and lead to system failure.

## How can pressure drop be minimized?

Pressure drop can be minimized by optimizing the design of the system, such as using larger diameter pipes to reduce friction, smoothing out rough surfaces, and minimizing the number of bends and turns in the system. Proper maintenance and regular cleaning of the system can also help reduce pressure drop.

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