1.2.1. Energy Losses in Pipes

But if you go to the outer layers where we look it that a velocity defect concept, how far the velocity from average velocity, that the defect means how much deviations how much difference between that. If you look it that and looking... (Refer Slide Time: 27:31)

In fluid dynamics, especially in the context of pipes, the term 'velocity defect' refers to how much the velocity of the fluid deviates from the average velocity. In other words, it's a measure of how smoothly the fluid is flowing. In the outer layers of fluid flow, where turbulence is present, we notice significant differences in the velocity of the fluid compared to the average. Understanding this concept is crucial as it allows engineers to predict flow patterns and potential energy losses in pipes due to turbulence.

Consider a group of runners in a race. If most runners average around 10 km/h, but some runners are sprinting at 15 km/h while others jog at 5 km/h, the discrepancies between these speeds represent their 'velocity defects' compared to the average. Just like the runners, fluid particles in a pipe move at different speeds, impacting the overall efficiency and energy loss in the system.

Many of the times you have the pipes in series, pipes in parallel or three reservoir junction problems. Pipe in series is a very simple problems like electric circuits, okay. You can have a series of wires you have from point A to B. If you have definitely the discharge will be for a steady state conditions for steady flow conditions. So discharge at the Q1, Q2, Q3 that should be equal because this is a steady state.

When considering pipes arranged in series, the concept is analogous to an electrical circuit where current flows through a series of resistors. In hydraulic systems, as water flows through successive pipes, the discharge (or flow rate) remains constant provided the conditions are steady. However, energy losses occur due to friction and other factors, and the total head loss in a series of pipes is the sum of the head losses for each individual pipe.

Imagine a long slide at a playground that consists of several segments. As children slide down each segment, they might slow down due to friction with the surface. Regardless of how many segments there are, if one child starts at the top, the same amount of energy is required to reach the bottom—albeit distributed among all segments, similar to water flowing through pipes.

But when you have a pipe in a series please remember it that you always should consider whether there are minor losses. There is major losses which is the frictional losses component for the pipe 1. Also there will be a minor losses because the change of the diameter of the pipe, okay there will be expansion or the contraction exit loss, entry losses all the loss component...

Energy losses in pipe systems can be categorized into major and minor losses. Major losses are primarily due to friction as fluid moves through the pipe's length, while minor losses occur at junctions, bends, and changes in diameter. Both types of losses must be accounted for in calculations to ensure an accurate assessment of the total energy losses experienced by the fluid.

Think of driving a car on a winding road. The friction between the tires and road represents major losses as you drive straight. However, every time you make a turn or go up a hill, you have to exert extra effort, which corresponds to minor losses. Understanding both helps you gauge how much energy is used on your journey.

Now if you look at another very simple problems that pipes in parallel. When you have a pipe in parallels, you can understand it see if I have the pipe in the parallels, there are three pipes are connected here. This is the A is entry point, B is exit point... (Refer Slide Time: 32:05)

In parallel pipe systems, fluid can take multiple paths through different pipes, and energy losses are equal across all paths. The overall flow is separated among these pipes, but regardless of the route chosen, the sum total of energy losses remains constant. This property is essential for ensuring that systems can manage flow effectively and maintain required pressures.

Picture a busy street where traffic can either take the left lane or the right lane at an intersection. Although cars may split between the two lanes, the total number of cars entering and leaving the intersection remains the same. Similarly, in parallel pipes, while the flow can divide, the energy required to maintain that flow stays equal overall.

Now we are coming back to the very simple examples okay. And that is what is in your textbook is necessary to for. If you look at these three flow one could be also outflow...

In a three reservoir junction problem, multiple reservoirs connect through pipes, and the flow direction can vary based on demand. The principle of conservation of mass applies, meaning the total incoming flow equals the outgoing flow. Additionally, it becomes essential to calculate how much energy loss occurs at junctions, helping to plan effective routing of fluid to maintain necessary pressure throughout the system.

Imagine a water park where three slides converge into a single pool. Water from each slide must flow into the pool without overflowing. The balance—the amount coming from each slide must equal what flows out—is crucial for efficient operation. Similarly, engineers analyze flow rates and energy losses at junctions to ensure proper water management.

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