Quick Answer: What Are The Classifications Of Heat Exchangers?

What are the examples of heat exchanger?

 Common examples of heat exchangers are shell-and tube exchangers, automobile radiators, condensers, evaporators, air preheaters, and cooling towers.

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Aim and Application of HE  There could be internal thermal energy sources in the exchangers, such as in electric heaters and nuclear fuel elements..

What are the two types of heat exchangers?

Types of Heat ExchangersShell and tube heat exchangers.Double pipe heat exchangers.Plate heat exchangers.Condensers, evaporators, and boilers.

Why baffles are provided in heat exchanger?

The main roles of a baffle in a shell and tube heat exchanger are to: Hold tubes in position (preventing sagging), both in production and operation. Prevent the effects of steam starvation, which is increased with both fluid velocity and the length of the exchanger. Direct shell-side fluid flow along tube field.

How do you calculate Reynolds number in heat exchanger?

The Reynolds number (Re) of a flowing fluid is calculated by multiplying the fluid velocity by the internal pipe diameter (to obtain the inertia force of the fluid) and then dividing the result by the kinematic viscosity (viscous force per unit length).

How are heat exchangers classified?

Heat exchangers are classified according to transfer processes into indirect- and direct- contact types. FIGURE 1.2 (a) Classification according to process function; (b) classification of condensers; (c) classification of liquid-to-vapor phase-change exchangers. exchanger as a regenerator.

What is a 1/2 Heat Exchanger?

Shell and tube heat exchanger design. … 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. In a single pass heat exchanger, the fluid goes in one end of each tube and out the other.

What are 3 types of heat?

The Three Mechanisms of Heat Transfer: Conduction, Convection, and Radiation.

Why are heat exchangers used?

Heat exchangers are widely used in industry both for cooling and heating large scale industrial processes. … In many industrial processes there is waste of energy or a heat stream that is being exhausted, heat exchangers can be used to recover this heat and put it to use by heating a different stream in the process.

Is boiler a heat exchanger?

A boiler works by using hot gas to heat water – and a heat exchanger is what allows this to happen. … A condensing gas boiler is able to recycle this heat from the waste gases and use it to heat the water. Condensing gas combi boilers used to have two heat exchangers, as it’s thought that this was more efficient.

What is heat duty of heat exchanger?

The Heat duty can be defined as the amount of heat needed to transfer from a hot side to the cold side over a unit of time. … The other can be used for latent heat transferred, this means that the fluid undergoes a phase change. i.e. condenses.

How many types of exchangers are there?

The two main types are finned and unfinned tubular. With a finned tubular heat exchanger, both fluids are unmixed, the one between the fins is guided in a direction transverse to the tube flow direction. In the unfinned exchanger heat can be exchanged in all directions, and the fluid can mix.

What are the 4 types of heat transfer?

Various heat transfer mechanisms exist, including convection, conduction, thermal radiation, and evaporative cooling.

Which mode of heat transfer is most efficient?

conductionThe most efficient method of heat transfer is conduction. This mode of heat transfer occurs when there is a temperature gradient across a body. In this case, the energy is transferred from a high temperature region to low temperature region due to random molecular motion (diffusion).

Where are double pipe heat exchangers used?

Double pipe heat exchangers are relatively cheap to construct and require minimal maintenance. They are used in high temperature and high pressure applications for sensible heating or cooling [3].

What type of heat exchanger is a condenser?

It is a shell and tube heat exchanger installed at the outlet of every steam turbine in thermal power stations. Commonly, the cooling water flows through the tube side and the steam enters the shell side where the condensation occurs on the outside of the heat transfer tubes.

What is the principle of heat exchanger?

Heat exchangers work because heat naturally flows from higher temperature to lower temperatures. Therefore if a hot fluid and a cold fluid are separated by a heat conducting surface heat can be transferred from the hot fluid to the cold fluid.

What are three ways to transfer heat?

A fire spreads by transferring heat energy in three ways: Radiation, Convection, and Conduction. Radiation refers to the emission of energy in rays or waves. Heat moves through space as energy waves.

How do you calculate the number of heat exchangers on a tube?

4.0 – HEAT EXCHANGERS CALCULATIONS:The main basic Heat Exchanger equation is: Q = U x A x ΔTm =The log mean temperature difference ΔTm is: ΔTm =(T1 – t2) – (T2 – t1) = °F.T1 = Inlet tube side fluid temperature; t2 = Outlet shell side fluid temperature;ln (T1 – t2) (T2 – t1)