The working principle of the heat exchanger are heat transfer from the high temperature end to the low temperature section.
U-tube heat exchanger tube course each tube is bent into a U-shape, the two ends of the tube were installed on both sides of the same fixed tube plate, and the head with a partition plate into two chambers, each tube can be automatically contracted, and other tubes and shells have nothing to do.
Even if the temperature difference between the shell and the tube is very a when also used, the actual production of circulating water cooling high temperature gas will be commonly used U-tube heat exchanger, heat exchanger tube corrosion or leakage can be changed only after the core, but should not be cleaned.
U-tube manometer is the longest history of measuring pressure instruments. It is used in vacuum measurement belongs to the absolute vacuum gauge, can be used as a vacuum measurement standard. Its typical principle structure is shown in the figure on the right. It consists of two measuring tubes, by measuring the height difference h of the working liquid column in the tube, the value of the pressure P to be measured can be calculated. One side of the liquid column needs to be vacuumed and other methods to make the pressure P0 on it compared to the pressure P to be measured.
Can be ignored, the accuracy of this manometer and the lower limit of measurement, mainly depends on how to measure the height difference between the surface of the liquid column h and the accuracy of the measurement of h, as well as the density of the working liquid. There are many ways to measure h, such as measuring directly with a scale, using altimeter, point contact micrometer, optical interferometry and so on, of which the interferometric method has the highest accuracy.
The earliest working liquid used is mercury, and in the vacuum measurement in order to expand to the low-pressure range, also commonly used saturated vapor pressure is low and density and viscosity of small oils. This manometer can measure low and medium vacuum.
What is the working principle of tube heat exchanger?
Tube heat exchanger, also known as shell and tube heat exchanger, tube heat exchanger works as follows:
Shell and tube heat exchanger has a multi-layer material with good thermal conductivity characteristics stacked into the principle of work and water heaters are similar.
The water heater is generated by the gas combustion heat and heat exchanger is the medium of heat is not an open flame, heat exchanger inside the two piping circuits, one is the heat source and the other is the source of the heated source of heat, such as hot water, such as hot water or steam, etc., the combustion of water heaters when the flame.
The heated source is like the water heated in the water heater. There is also a regulating valve in front of the heat source inlet of the heat exchanger in the heat source circuit by changing the opening of this valve you can adjust the temperature of the heated source.
Tubular heat exchanger is the most typical inter-wall heat exchanger, which has a long history of industrial applications and still dominates all heat exchangers. Tube heat exchanger mainly has a shell, tube bundle, tube plate and head and other parts of the shell is mostly round, the internal parallel tube bundle, tube bundle ends are fixed on the tube plate.
Reference:
The working principle of the heat exchanger
Principle: The compressor compresses the refrigerant into a high-pressure saturated gas, and this gaseous refrigerant then passes through the condenser to condense.
After throttling through the throttling device, it is passed into the evaporator to cool the medium to be cooled for heat exchange. For example, if the evaporator is connected to each room in the building, the serpentine tubes inside the evaporator will exchange heat with the air, and then blow the cool air to the air in the room through the blower.
And the evaporator serpentine tube refrigerant heat transfer into low-pressure vapor back to the compressor, and then be compressed by the compressor, so that the cycle of utilization to complete the refrigeration system.
Heating and refrigeration principle is the same, that is, the inverse Carnot cycle, and refrigeration principle is different from the condenser and evaporator exchange, that is: compressor-evaporator-throttle device-condenser.
Extended information:
Thermal sensing heat exchanger unit features
1, rapid heat transfer, heat transfer efficiency, heat transfer efficiency up to 100%.
2, the condensate is fully recovered, recycling, the entire system water self-cleaning anti-scaling, heat exchangers, radiators and heat transfer system can maintain long-term stable and efficient heat exchange performance, minimize the system scaling phenomenon, will not be difficult to overcome the scaling drawbacks and reduce the efficiency of the system heat transfer.
3, the heat exchanger is made of stainless steel, the product structure is designed scientifically, the craft is well made, the service life is long, up to more than 20 years.
4, the key components of the German advanced technology and order processing, so that the host is not affected by the steam pressure and system pressure, effectively eliminating the noise, the phenomenon of vapor strikes, the whole machine running smoothly.
5, condensate is completely absorbed and utilized, the system has no special reasons, no need to set up water replenishment device, greatly saving the system water and operating costs.
6, the whole set of compact structure, covers an area of small, greatly saving the investment in civil engineering, at the same time, due to the heat transfer efficiency is very high, the system does not need to replenish the water, the whole set of steam-saving, power-saving, water-saving trinity, for the user to create considerable energy-saving benefits.
7, the unit has a highly intelligent automation control function, can realize the overpressure, over-temperature protection, power outage steam automatic cut-off and outdoor temperature automatic compensation function and can realize remote monitoring, to provide users with a worry-free operation platform.
8, a wide range of applications, can be widely used in thermoelectricity, factories and mines, food and medical, machinery and light industry, civil construction and other fields of heating, hot water bathing and other purposes.
9, wide application conditions, can be used for heat exchange of larger pressure, temperature range.
Reference:
Tube Heat Exchanger Schematic and Classification Explained
With the deepening of people's understanding of the heat, the demand for more and more, a lot of people at work or in the life of the regular will Hear will see such a thing - heat exchanger. Heat exchanger is a device that transfers heat energy from a hot fluid body to a cold fluid body to meet the specified process requirements, is an industrial application of convective heat transfer and heat conduction. Simply put, it is also a container with a large internal contact surface and relatively sealed. Household heat exchangers are more common, let's talk about today's more widely used in the industrial field of tube heat exchanger.
Basic Concept
Tube heat exchanger in the heat transfer of the two fluids, a flow in the tube, the trip is called the tube; a flow outside the tube, the trip is called the shell process. The wall of the tube bundle is the heat transfer surface. In order to improve the heat transfer coefficient of the fluid outside the tube, usually installed in the shell of a certain number of transverse folding plate. Folding plate can not only prevent fluid short-circuit, increase the fluid velocity, but also force the fluid in accordance with the specified path many times through the tube bundle, so that the degree of turbulence is greatly increased. Commonly used stall plate has a round lack of shape and disc-shaped two kinds, the former is more widely used.
Fluid in the tube every time through the bundle is called a tube, every time through the shell is called a shell process. In order to improve the speed of the fluid in the tube, can be set up in the two ends of the head inside the appropriate partition, all the tube evenly separated into a number of groups. In this way, the fluid can only pass through part of the tube each time and go back and forth to the tube bundle for many times, known as multi-pipe process. Similarly, in order to improve the flow rate outside the tube, the shell can be installed in the shell longitudinal stalls so that the fluid through the shell space many times, called multi-shell process. In a tube heat exchanger, the temperature of the shell and tube bundle is different due to different fluid temperatures inside and outside the tubes.
Basic classification
Fixed tube and plate type
Fixed tube and plate type heat exchanger is the two ends of the tube plate is welded directly to the shell. It is mainly composed of shell, tube plate, tube bundle, head and other main components. Shell set in the tube bundle, tube bundle ends using welding, expansion or expansion welding and have the method of tube fixed in the tube plate, tube plate around the outside and the head flange with bolts fastened. Fixed tube-plate heat exchanger structure is simple, inexpensive, easy to manufacture, easy to clean and repair the tube course, but the shell course is difficult to clean, the tube bundle after the manufacture of temperature difference stress exists. When the heat exchanger tube and shell have a large temperature difference, the shell should also have an expansion joint.
Floating head type
Floating head type heat exchanger one end of the tube plate is fixed between the shell and the tube box, the other end of the tube plate can be free to move in the shell, that is, the shell and the bundle of thermal expansion can be free. Therefore, there is no temperature difference stress between the tube bundle and the shell. The general floating head can be dismantled, the tube bundle can be freely withdrawn and loaded. Floating head heat exchanger of this structure can be used in the tube bundle and shell have a large temperature difference between the working conditions. The cleaning and maintenance of the tube bundle and shell are more convenient, but its structure is relatively complex, and the requirements for sealing are also higher.
"U"-shaped tube
U-shaped tube heat exchanger is the heat exchanger tube Wei into a U-shaped, the two ends are fixed on the same tube plate. Because the shell and the heat exchanger tube is separated, the heat exchanger tube bundle can be free to expand and contract, will not be due to the temperature difference of the medium and the temperature difference stress. u-tube heat exchanger has only one tube plate, there is no floating head, the structure is relatively simple. Tube bundle can be freely drawn out and loaded, easy to clean, with the advantages of floating head type heat exchanger, but because the heat exchanger tube into a U-shaped bend of varying radius, the outermost heat exchanger tube can be replaced after damage, other tube damage can only be plugged. At the same time, it is compared with the fixed tube plate heat exchanger, due to the heat transfer tube by the limitations of the bending radius of the center part of the tube bundle there is a gap, the fluid is easy to go short-circuit, affecting the heat transfer effect.
The above is commonly used in industry, tube heat exchanger classification and sub-categorization of the structure of the schematic diagram, the principle of simple and complex design, process, material requirements are also higher, the purpose is to enhance the heat exchanger heat transfer efficiency. However, the tube heat exchanger because of its special tubular structure, in the process of using the fluid must contain some impurities, etc., it is difficult to thoroughly clean. This also results in a waste of resources, time and manpower for the enterprise, the future in the cleaning will be the main direction of development.