Blood is a liquid with dark red color flowing through the human body. It has the duty of oxygen transfer from lungs to cells of the body. Blood contains red and white cells and also some other parts like plackets. Here human blood is 19x magnified.
Jasmine is a flower with over 200 species. It can be white, yellow, reddish or blue. This flower grows in warn regions of Africa, Asia and Europe. This plant has small flowers. The leaves of this plant can fall in autumn or can be green all year. The leaf and flower of this plant are magnified by 19x here.
Rose is flower with over hundred species over the world. The color can be white, yellow, red or combined colors. This plant with small or big flowers can grow from several centimeters to several meters. The name rose come from the French word “rosa” and the origin of this word goes back to Old Persian. Hear the rose plant leaf in shown under microscope with 19x magnification.
Portulaca Oleracea is a small plant of about 30 to 40 cm height. It has small leaves. The plant distribution in so vast globally, starting from Africa to Middle East to Malaysia to Australia. As a result the origin of this plant is not certainly determined. Due to its root, it can grow in poor soils. Hear a fresh and an old Portulaca Oleracea leaf is magnified by microscope to 19x.
Lettuce is a plant grown on ground with height of 20 to 30 centimeters. It is mostly used for its leaves. This plant was first grown by ancient Egyptians. The name lettuce comes from the Greek word “lactuca”. This plant is a source of vitamins and is used globally as salad, in sandwiches, soups, etc. the following image shows a lettuce leaf magnified 19x larger.
In the first part of this article, heat exchanger design basics were introduced. In the following article, the design formulations and calculations are introduced.
As mentioned in part 1, overall heat transfer in heat exchanger in increased in the flow are set to be countercurrent. As a result, only countercurrent double pipe heat exchanger design is discussed here. To start the design of a double pipe heat exchanger, the first step is to calculate the heat duty of the heat exchanger. It must be noted that for easier design, it’s better to ignore heat loss in heat exchanger for primary design. The heat duty can be defined as the heat gained by cold fluid which is equal to the heat loss of the hot fluid. It can be calculated as:
Reciprocating compressor is the earliest compressor type with wide range of application from consumer to industrial usages. These compressors are manufactured in the broad range of configurations and the pressure range is wider than other types of compressors beginning from vacuum to 40000 psig. Higher maintenance cost and lower capacity of reciprocating compressors in comparison with centrifugal compressors have reduced the population of this type since late 1950s to the mid-1970s. But recent rises in energy cost and the advent of new specialty process plants have given the reciprocating compressors a more prominent role in the design of new plants.
Compressors are mechanical devices used to increase the pressure of gas or vapor to be transferred from one point to another through a pipe.
Double pipe heat exchangers are the simplest exchangers used in industries. On one hand, these heat exchangers have low cost for both design and maintenance, making them a good choice for small industries. But on the other hand, low efficiency of these exchangers beside high space occupied for such exchangers in large scales, has led modern industries to use more efficient heat exchanger like shell and tube or other modern heat exchangers. But yet, since double pipe heat exchangers are simple, they are used to teach heat exchanger design basic to students and as the basic rules for modern and normal heat exchangers are the same, students can understand the design techniques much easier.
Heat exchangers (HEX) are one of the most important parts of industries like chemical, medical, or many other industries. These systems are used to transfer or “exchange” thermal energy (heat) between two fluids which can be gas or liquid. Heat exchangers can be found in different types such as double pipe, shell & tube, spiral tube, plate, etc. but the two first types are and specially shell & tube exchangers are more common in industries.