What Is Meant By Parallel Flow Heat Exchanger? - Fixanswer

A counter-flow heat exchanger is one in which the direction of the flow of one of the working fluids is opposite to the direction to the flow of the other fluid . In a parallel flow exchanger, both fluids in the heat exchanger flow in the same direction.

What is meant by parallel flow?

a pattern of movement of working liquids or gases in a heat exchanger whereby fluids divided by a wall flow in identical directions ; the heat transfer occurs through the wall.

Which is better parallel flow or counterflow?

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. ... Each time a fluid moves through the length is known as a pass.

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

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.

Where is parallel flow heat exchanger used?

However, there are applications where parallel flow has its benefits, such as when limiting the transfer of heat is recommended. Another advantage if parallel flow heat exchangers are used is that outlet temperature of the fluid being cooled can reach a limiting temperature .

What type of flow has better heat transfer in a coil?

Each of the three types of heat exchangers (Parallel, Cross and Counter Flow) has advantages and disadvantages. But of the three, the counter flow heat exchanger design is the most efficient when comparing heat transfer rate per unit surface area.

Which flow is better in heat exchanger?

Where two fluids are expected to be taken to exactly the same temperature, the parallel flow configuration is beneficial. While the counter flow heat exchanger has more significant advantages compare to parallel flow design.

How do you calculate effective heat exchanger?

If one of the fluids is undergoing a change of phase throughout the entire heat exchanger and at a constant temperature (i.e. heat capacity is infinite), the thermal efficiency is simply Eff=1-exp(-U.A/Cmin) , where Cmin is the heat capacity (m x cp) for the single phase fluid, U-overall heat transfer coeffcient and A ...

What is NTU in heat exchanger?

From Wikipedia, the free encyclopedia. The Number of Transfer Units (NTU) Method is used to calculate the rate of heat transfer in heat exchangers (especially counter current exchangers) when there is insufficient information to calculate the Log-Mean Temperature Difference (LMTD).

Why do we use LMTD in heat exchanger?

The log mean temperature difference (LMTD) is used to determine the temperature driving force for heat transfer in flow systems , most notably in heat exchangers. The LMTD is a logarithmic average of the temperature difference between the hot and cold streams at each end of the exchanger.

Which type of flow arrangement gives maximum heat transfer?

The counter flow pattern is the most common in shell and tube heat exchangers, primarily because it's the most efficient. This flow pattern allows for the greatest temperature change between fluids.

Why is graphite heat exchanger the most efficient?

Advantages of Graphite Cubic Blocks

Graphite is a more thermally efficient material of construction , typically using 1/2 to 1/3 the heat transfer area required by a glass unit. Graphite is more robust and can be subjected to greater pressure. In sulfuric acid dilution.

What is the difference between mixed and unmixed fluids in cross flow heat exchanger?

What is the difference between mixed and unmixed fluids in cross-flow? In a counter flow heat exchanger, the hot and cold fluids enter the heat exchanger at opposite ends and flow in opposite direction. But in case of cross flow heat exchanger, the two fluids usually move perpendicular to each other .

What are the disadvantages of plate heat exchangers?

Initial cost is high since Titanium plates are expensive.
Finding leakage is difficult since pressure test is not as ease as tube coolers.
Bonding material between plates limits operating temperature of the cooler.
Pressure drop caused by plate cooler is higher than tube cooler.

What is the difference between co current heat exchanger and counter current heat exchanger?

One is termed a cocurrent heat exchanger, while the other is termed a countercurrent heat exchanger. In the cocurrent mode, both the hot and cold streams enter the heat exchanger at one end, and leave at the opposite end. In the countercurrent mode, the streams enter at opposite ends of the heat exchanger.