rajibray

Finned Tube Exchanger: In a heat exchanger, while heating the air outside the tubes with steam inside the tubes, the steam side coefficient will be very high and the airside coefficient will be extremely low. While heat transfer, as the overall coefficient approximates that of the lower side (the airside coefficient), the only remedy to … Read more

Scraped Surface Exchangers: In some of the heat interchangers the drag forces due to the flow of viscous liquid, a quite thick viscous sub-layer or due to turbulent conditions in the core, liquid exhibits no pressure loss with excessive pumping costs. This problem is solved by physically removing the layers of fluid at the heat … Read more

Double pipe heat interchangers are efficient equipment for heat transfer as they have a few pipes (tubes) per pass. Construction of Double Pipe Heat Interchangers The double-pipe heat interchanger uses two pipes arranged as one inserted into the other, Figure given below. The inner pipe is used for the pumping of cold fluid to be … Read more

The liquid-to-liquid heat interchanger is single-pass equipment wherein the fluid to be heated is passed only once through the tubes before it gets discharged. Thus, the heat transfer in this case is not efficient. The basic construction includes a few modifications, and its functioning remains approximately the same. Working Baffles are placed outside the tubes. … Read more

Most of the chemical and pharmaceutical industries uses a variety of heat transfer equipments. The materials to be heated may be liquids, gases or solids. A heated fluid or condensed steam is used as the heating medium. In pharmacy, operations involved in heat transfer includes preparation of starch paste for granulation, crystallization, evaporation, distillation etc. … Read more

The shell and tube heat exchanger are the most commonly used heat exchangers in the chemical process industries. This type of heat exchanger consists of a bundle of tubes properly secured at the ends in tube sheets. The metal sheets have holes into which the tubes are fixed up to have leak-proof joints. The entire … Read more

A heat exchanger is a device that transfers heat from one fluid (a liquid or gas) to another fluid (another liquid or gas), with the two fluids being at different temperatures and in thermal contact. There are usually no external heat and work interactions in heat exchangers. Transfer processes, number of fluids, degree of surface … Read more

Heat transfer mechanisms are simply ways by which thermal energy is transferred between objects. It is based on the basic principle that kinetic energy tries to be at equilibrium or at equal energy states. There are three different ways for heat transfer to occur, namely conduction, convection, and radiant heat. One more related phenomenon that … Read more

Fourier’s law is another name for the law of heat conduction. “The time rate of heat transmission through a material is proportional to the negative temperature gradient and to the area,” it says. The Fourier’s equation of heat conduction is expressed as equation (4.1) Where, Q is the heat flow rate by conduction (W), k … Read more