#Tube condenser calculations series#

Tightening bolts fitted between the plates are used to compress the plate pack between the frame plate and the pressure plate. In a gasketed plate heat exchanger the plates are clamped together in a frame, and a thin gasket (usually a synthetic polymer) seals each plate around the edge. Gasketed plate heat exchangers (plate and frame heat exchangers) This can eliminate the need for a separate sub-cooler or flash steam recovery system.ДЄlthough a nominal heat transfer area may theoretically be calculated using Equation 2.5.3, plate heat exchangers are proprietary designs and will normally be specified in consultation with the manufacturers. If the condensate is drained to an atmospheric receiver, by reducing the condensate temperature, the amount of flash steam lost to the atmosphere through the receiver vent is also reduced. However, recent design advances mean that plate heat exchangers are now equally suited to steam heating applications.ДЄ plate heat exchanger may permit both the condensing and sub-cooling of condensate within a single unit. The steam heat exchanger market was dominated in the past by the shell and tube heat exchanger, whilst plate heat exchangers have often been favoured in the food processing industry and used water heating. The plates will usually be coated on the primary side, in order to promote the dropwise condensation of steam. The promotion of turbulent flow also eliminates the presence of stagnant areas and thus reduces fouling. This pattern also creates turbulent flow in the channels, improving heat transfer efficiency, which tends to make the plate heat exchanger more compact than a traditional shell and tube heat exchanger. Figure 2.13.3 shows a schematic representation of a plate heat exchanger.ДЄ corrugated pattern of ridges increases the rigidity of the plates and provides greater support against differential pressures. Heat transfer takes place from the primary fluid steam to the secondary process fluid in adjacent channels across the plate.

#Tube condenser calculations series#

However, it is important to note that throughput as given on the pump makerвЂ™s plate will probably relate to a pressure head, which may or may not be present in practice.ДЄ plate heat exchanger consists of a series of thin corrugated metal plates between which a number of channels are formed, with the primary and secondary fluids flowing through alternate channels. On existing plant, an indication of actual load may be obtained if the flow and return temperatures and the pumping rate are known. In many cases, plate heat exchangers are oversized simply to reduce the pressure drop for the secondary fluid. However, there is more flexibility in the sizing of gasketed plate heat exchangers, where plates can often be added or removed to achieve the desired heat transfer area. Plate heat exchangers may also be chosen from a standard range of sizes if the units are brazed or welded. For the hot water heating of buildings there may also be certain safety factors included in the heat load calculations. However, heat exchangers (particularly shell and tube) are frequently too large for the systems which they are required to serve.ДЄ non-storage calorifier (as shown in Figure 2.13.2) will normally be selected from a standard range of sizes, and may often have a much larger capacity than the design figure. Manufacturers often provide a thermal rating for their heat exchangers in kW, and from this the steam consumption may be determined, as for air heater batteries. (A storage calorifier, as shown in Figure 2.13.1, is constructed differently, it usually consists of a hot water storage vessel with a primaryВ heatingВ coilВ inside). A shell and tube heat exchanger used to heat water for space heating (using either steam or water) is often referred to as a non-storage calorifier. However, the term is often more specifically applied to shell and tube heat exchangers or plate heat exchangers, where a primary fluid such as steam is used to heat a process fluid. Similarly, a steam boiler where combustion gases give up their heat to water in order to achieve evaporation, may be described as aВ firedВ heatВ exchanger. A domestic radiator, where hot water gives up its heat to the ambient air, may be described as a heat exchanger. The term heat exchanger strictly applies to all types of equipment in which heat transfer is promoted from one medium to another.