Why passes are provided in the tube side of the shell and tube heat exchangers?

They are used to boil water recycled from a surface condenser into steam to drive a turbine to produce power. Most shell-and-tube heat exchangers are either 1, 2, or 4 pass designs on the tube side. This refers to the number of times the fluid in the tubes passes through the fluid in the shell.

Which flow is better in heat exchanger?

The counter-flow heat exchanger has three significant advantages over the parallel flow design. First, the more uniform temperature difference between the two fluids minimizes the thermal stresses throughout the exchanger.

Which type of flow arrangement gives maximum efficiency in a shell and tube heat exchanger and why?

The best design for shell and tube and double-pipe exchanger is counter flow configuration, and the heat transfer between the fluid is the maximum. In counter flow, the efficiency is higher than the parallel, and temperature in the cooling fluid outlet can exceed the warmer fluid inlet temperature.

Why is shell and tube heat exchanger good?

Shell and tube heat exchangers make it possible to pump materials as soon as possible, and they transfer temperatures efficiently so you can ensure the materials are at the necessary temperature without expending extra energy to do so.

What are tube side and shell-side fluid flow?

These two integral pathways are usually built out of thermally conductive metals that allow easy heat transfer (steel, aluminum alloys, etc.). The tubes carry a fluid from their inlet to their outlet (the “tube-side” flow), while the shell passes a separate fluid over these tubes (the “shell-side” flow).

What is the advantage of a cross flow versus a parallel flow heat exchanger?

Advantages and Disadvantages of Cross Flow Heat Exchangers Thermodynamically, the effectiveness of a cross flow heat exchanger is better than counter flow and parallel flow heat exchangers. Logarithmic mean temperature difference (LMTD) will always be greater for cross flow compared to a parallel flow heat exchanger.

Which of the following is advantage of multipass heater?

. 10.2 Multipass heater The main advantage of Multipass heater is to improve velocity of fluid.

Which heat exchanger is more efficient and why?

Counter flow heat exchangers are inherently more efficient than parallel flow heat exchangers because they create a more uniform temperature difference between the fluids, over the entire length of the fluid path.

Why is countercurrent flow more efficient than parallel flow?

The cooling medium heats up as it travels through the heat exchanger, but as colder water enters the heat exchanger, it absorbs more heat, reducing the temperature much lower than could be achieved with parallel flow.

Why the counter flow is preferable than the parallel flow in condensers?

Counter flow heat exchangers are the most efficient of the three types. In contrast to the parallel flow heat exchanger, the counter flow heat exchanger can have the hottest cold- fluid temperature greater than the coldest hot-fluid temperatue.

How efficient are shell and tube heat exchangers?

Plate heat exchangers are up to five times more efficient than shell-and-tube designs….Overall Heat Transfer Coefficient (U Value)

Can a heat exchanger have more than one pass?

Multiple Passes. Shell-and-tube heat exchangers can have multiple passes, such as 1-1, 1-2, 1-4, 1-6, and 1-8 exchangers, where the first number denotes the number of the shells and the second number denotes the number of passes. An odd number of tube passes is seldom used except the 1-1 exchanger.

What are the advantages of a shell side heat exchanger?

In this context we don’t have to put expensive material (costly corrosion resistant alloys (MOC)) in the whole shell side, which reduces the heat exchanger cost significantly. Low pressure drop: If you want low pressure drop when the fluid flow then pass it through shell side.

What is the distance between two baffles in a heat exchanger?

The distance between two baffles is baffle spacing. Shell-and-tube heat exchangers can have multiple passes, such as 1-1, 1-2, 1-4, 1-6, and 1-8 exchangers, where the first number denotes the number of the shells and the second number denotes the number of passes.

Why does the fluid pass from shell side to tube side?

For viscous fluids : If the fluid is viscous in nature it should of-course pass from shell side. Due to the presence of baffles velocity of flow increases causes high pressure drop as a result high heat transfer coefficient. If you pass from tube side this tends to have high pressure drop and low heat transfer.