How can the efficiency of a heat exchanger be increased?

Conventional shell and tube heat exchangers use simple segmental baffles. It can be replaced by helical baffles, which increase the heat transfer efficiency and reduce pressure losses. Their usage is demonstrated in the primary circuit of IV.

Does heat transfer increase with flow rate?

In other words, the rate of heat transfer is directly proportional to mass flow rate. If you increase the flow rate, you will then increase the rate of heat transfer.

What are the advantages of the flow through coil tube in comparison to the straight tube?

The swirling motion produced by coiling a tube increases the frictional pressure drop and the average heat transfer coefficient compared with those in a straight pipe of the same total (uncoiled) length.

What is effective heat exchanger?

The effectiveness (ϵ) of a heat exchanger is defined as the ratio of the actual heat transfer to the maximum possible heat transfer.

How does fluid velocity affect heat transfer?

The fluid motion enhances heat transfer (the higher the velocity the higher the heat transfer rate). The convective heat transfer coefficient h strongly depends on the fluid properties and roughness of the solid surface, and the type of the fluid flow (laminar or turbulent).

Why does heat transfer increase with velocity?

Heat transfer coefficient is the ability of fluid to transfer heat when it comes in contact with a solid surface. Higher flow rate (velocity) indicates higher generattion of eddies. These eddies are responsible for heat transfer. Hence higher flow rate, higher the heat transfer rate.

How the type of fluid affects the heat transfer coefficient?

Heat transfer coeficiente depends on the kind of fluid involved. Each fluid has its own thermal properties, which can be found in published tables and books. Thermal conductivity of a given material that receives thermal energy by means of some fluid affects the heat transfer process, too.

How does heat transfer coefficient increase tube side?

The shell side heat transfer coefficient is improved by providing baffles on the shell side and creating cross flow of shell side fluid with respect to the tube bundle. The commonly used baffle is the segmental baffle.

What is the purpose of a helical heat exchanger?

Helical geometry permits handling of high temperatures and extreme temperature differentials without high induced stresses or costly expansion joints. High-pressure capability and the ability to fully clean the service-fluid flow area add to the exchanger’s advantages.

What is a good heat exchanger effectiveness?

With those factors embedded into industry calculations, plate heat exchangers are still consistently found to be the most efficient of all heat exchangers. Typically, they can achieve efficiency rates of approximately 90\%.