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2025-03-13 11:57:41 João Lopes: -/-
Utilidades industriais/Equipamentos/Permutadores de Carca\303\247a e Tubo.md ..
@@ 1,303 1,303 @@
- <img src="./fa4pc54n.png"
- style="width:3.085in;height:1.71389in" />
-
- > Departamento de Engenharia Química
- >
- > Mestrado Integrado em Engenharia Química
- >
- > Integração e intensificação de processos
- >
- > Shell and Tubes Heat Exchangers
- >
- > **Docente** **Responsável:**
- >
- > Nuno Manuel Clemente de Oliveira
- >
- > **Integrantes** **do** **grupo:**
-
- João Victor Vieira
-
- > Matteo Gecchele
-
- <img src="./xvze01o4.png"
- style="width:5.90556in;height:2.24583in" />
-
- > **Introduction** **&** **Structure**
- >
- > The most common type of heat exchanger is the shell-and-tube, usually
- > used in a lot of industrial applications. This type of heat exchanger
- > has large number of tubes, sometimes several hundred, packed in a
- > shell with their axes parallel to that of the shell. The heat transfer
- > takes place between two fluid, one flowing inside the tubes and one
- > flowing outside the tubes through the shell. Baffles are commonly
- > placed in the shell to force the shell-side fluid to flow across the
- > shell to enhance heat transfer, to maintain uniform spacing between
- > the tubes and, also in order to maintain the turbulent flow inside the
- > exchanger. The baffle spacing is usually not greater than a distance
- > equal to the inside diameter or closer than a distance equal to
- > one-fifth the inside diameter of the shell.
- >
- > Usually the shell-and-tube heat exchangers have large size and weight,
- > and for this reason they are not using in automotive and aircraft
- > applications. At both ends of the shell, the tubes open to some large
- > flow areas, called headers, where the tube-side fluid accumulates
- > before entering the tubes and after leaving them.
- >
- > Shell-and-tube heat exchangers are further classified according to the
- > number of shell and tube passes involved. Heat exchangers in which all
- > the tubes make one U-turn in the shell, for example, are called
- > one-shell-pass and two-tube-passes heat exchangers. Likewise, a heat
- > exchanger that involves two passes in the shell and four passes in the
- > tubes is called a two-shell- passes and four-tube-passes heat
- > exchanger.
-
- <img src="./tnci3l31.png"
- style="width:2.85417in;height:1.78125in" /><img src="./cncqllod.png"
- style="width:2.57292in;height:2.02083in" />
-
- > **Operation** **principle**
- >
- > In order to calculate the temperature difference ∆𝑡 in a 1-2
- > exchanger, it is necessary to make some assumptions:
- >
- > 1\. The shell fluid temperature is an average isothermal temperature
- > at any cross section
- >
- > 2\. There is an equal amount of heating surface in each pass 3. The
- > overall coefficient of heat transfer is constant
- >
- > 4\. The specific heat of each fluid is constant 5. The flowrate of
- > each fluid is constant
- >
- > 6\. There are not phase change (evaporation or condensation) in a part
- > of the exchanger
- >
- > 7\. Heat losses are negligible
- >
- > The overall heat balance where ∆𝑡 is the true difference of
- > temperatures, is:
- >
- > 𝑄 = 𝑈𝐴∆𝑡 = 𝑊𝐶(𝑇 − 𝑇 ) = 𝑤𝑐(𝑡2 − 𝑡1) where U is the heat transfer
- > coefficient and A is the surface of contact.
- >
- > Shell-and-tube heat exchangers are complicated devices and the
- > simplified approaches should be used with care. In fact, it is assumed
- > that the overall heat transfer coefficient U is constant throughout
- > the heat exchanger and that the convection heat transfer coefficients
- > can be predicted using the convection correlations. However, in some
- > practical application, the predicted value of U can exceed 30 percent.
- > Thus, it is natural to tend to overdesign the heat exchangers in order
- > to avoid unpleasant surprises.
- >
- > Heat transfer enhancement in heat exchangers is usually accompanied by
- > increased
- >
- > pressure drop, and this causes higher pumping power. Therefore, any
- > gain from the enhancement in heat transfer should be balanced against
- > the cost of the accompanying pressure drop. Also, some thought should
- > be given to which fluid should pass through the tube side and which
- > through the shell side. Usually, the more viscous fluid is more
- > suitable for the shell side (larger passage area and lower pressure
- > drop) and the fluid with the higher pressure for the tube side.
- >
- > Usually, it is convenient to relate the equivalent temperature
- > difference to the log
- >
- > mean temperature difference relation for the counter-flow case as
- >
- > ∆ 𝑙𝑚 = 𝐹∆ 𝑙𝑚,𝐶𝐹
-
- where *F* is the correction factor**,** which depends on the geometry of
- the heat exchanger and the inlet and outlet temperatures of the hot and
- cold fluid streams. The
-
- > ∆𝑇𝑚,𝐶𝐹 is the log mean temperature difference for the case of a
- > counter-flow heat exchanger with the same inlet and outlet
- > temperatures.
- >
- > The correction factor *F* for a shell-and-tube heat exchanger is shown
- > in the figures below versus two temperature ratios *P* and *R* defined
- > as
- >
- > 𝑡2 − 𝑡1 𝑇 − 𝑡1
- >
- > 𝑇 − 𝑇 𝑡2 − 𝑡1
- >
- > where the subscripts 1 and 2 represent the inlet and outlet*,*
- > respectively. Note that for
- >
- > a shell-and-tube heat exchanger, *T* and *t* represent the shell-side
- > and tube-side temperatures, respectively.
-
- <img src="./gklfx0zi.png"
- style="width:5.02431in;height:4.35569in" />
-
- > **Factors** **that** **influence** **performances** *Fouling:*
- >
- > The performance of heat exchangers usually deteriorates with time as a
- > result of accumulation of deposits on heat transfer surfaces. The
- > layer of deposits represents additional resistance to heat transfer
- > and this causes a decrease of the rate of heat transfer in a heat
- > exchanger. The net effect of these accumulations on heat transfer is
- > represented by a fouling factor, which is a measure of the thermal
- > resistance introduced by fouling.
- >
- > For a shell-and-tube heat exchanger it possible to write the overall
- > heat transfer relation as
- >
- > 𝑈𝐴𝑠 = 𝑈𝐴𝑖 = 𝑈0𝐴0 = 𝑅 = ℎ𝑖𝐴𝑖 + 𝐴𝑖𝑖 + ln⁡𝑈0𝐴0 𝑖) + 𝐴0 + ℎ0𝐴0
- >
- > where 𝐴𝑖 = 𝐷𝐿 and 𝐴0 = 𝐷0𝐿 L are the areas of inner and outer
- > surfaces, and 𝑅,𝑖 and 𝑅,0 are the fouling factors at those surfaces.
- >
- > *Heat* *transfer* *rate:*
- >
- > The heat transfer rate is the most important parameter of a heat
- > exchanger. A heat exchanger should be capable of transferring heat at
- > the specified rate in order to achieve the desired temperature change
- > of the fluid at the specified mass flow rate.
- >
- > *Size* *and* *Weight:*
- >
- > The heat exchanger is better if it is smaller and lighter, in
- > particular, in the automotive and aerospace industries, where size and
- > weight requirements are most stringent. For this reason,
- > shell-and-tube heat exchangers cannot be used in this type of
- > application. Also, a larger heat exchanger normally carries a higher
- > price tag. The space available for the heat exchanger in some cases
- > limits the length of the tubes that can be used.
- >
- > *Material:*
- >
- > The thermal and structural stress effects need not be considered at
- > pressures below 15 *atm* or temperatures below 150*°C*. But these
- > effects are major considerations above 70 *atm* or 550*°C* and
- > seriously limit the acceptable materials of the heat exchanger.
- >
- > A temperature difference of 50*°C* or more between the tubes and the
- > shell will probably pose differential thermal expansion problems and
- > needs to be considered. In the case of corrosive fluids, we may have
- > to select expensive corrosion-resistant materials such as stainless
- > steel or even titanium.
- >
- > **Cost**
- >
- > The purchase cost of a shell and tube depends on the rear head type
- > and on the heat transfer
- >
- > area (size factor). The relationship between the purchase cost and the
- > size factor is
- >
- > represented in the graph below
-
- <img src="./s1x5d1ti.png"
- style="width:4.86667in;height:3.36917in" />
-
- > Both fluids are usually forced to flow by pumps or fans that consume
- > electrical power. The annual cost of electricity associated with the
- > operation of the pumps and fans can be determined from
- >
- > 𝑂𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔⁡𝐶𝑜𝑠𝑡 = 𝑃𝑢𝑚𝑝𝑖𝑛𝑔⁡𝑃𝑜𝑤𝑒𝑟⁡\[𝑘𝑊\] × 𝐻𝑜𝑢𝑟𝑠⁡𝑜𝑓⁡𝑂𝑝𝑒𝑟𝑎𝑡𝑖𝑜𝑛⁡\[ℎ\] ×
- > 𝑃𝑟𝑖𝑐𝑒𝑜𝑓⁡𝐸𝑙𝑒𝑐𝑟𝑖𝑐𝑖𝑡𝑦⁡\[\$ 𝑘𝑊ℎ\]
- >
- > where the pumping power is the total electrical power consumed by the
- > motors of the pumps and fans.
- >
- > Minimizing the pressure drop and the mass flow rate of the fluids will
- > minimize the operating cost of the heat exchanger, but it will
- > maximize the size of the heat exchanger and thus the initial cost. As
- > a rule of thumb, doubling the mass flow rate will reduce the initial
- > cost by half but will increase the pumping power requirements by a
- > factor of roughly eight. Typically, fluid velocities encountered in
- > heat exchangers range between 0.7 and 7 m/s for liquids and between 3
- > and 30 m/s for gases. Low velocities are helpful in avoiding erosion,
- > tube vibrations, and noise as well as pressure drop.
- >
- > **Advantages**:
- >
- > *Size:*
- >
- > Shell-and-tube heat exchangers are capable of providing a larger
- > surface area for heat transfer to take place while having a shorter
- > length overall due to presence of multiple tubes.
- >
- > *Heat* *duty:*
- >
- > Shell-and-tube heat exchangers can handle higher temperatures and
- > pressures and hence higher heat duty. This is because besides
- > providing a higher overall heat transfer coefficient, additions can
- > also be made to negate thermal expansion effects and the thickness can
- > also be varied (more in the next point).
- >
- > *Versatility:*
- >
- > From the design point of view, shell-and-tube heat exchangers are the
- > most versatile of all heat exchangers. Being tubular in shape, heads /
- > closures of required shape and thickness can be used. The number of
- > tubes and tube pitch can be selected according to operating
- > conditions. Expansion bellows can be used to negate thermal expansion
- > effects, baffles if different cuts and spacings can be used to
- > influence the overall heat transfer coefficients and there's even
- > something called a floating head which can be added to negate thermal
- > expansion of the tubes. The number of passes on shell side and tube
- > side can be altered as well.
- >
- > **Disadvantages**:
- >
- > *Size:*
- >
- > This can also be a disadvantage as at lower heat duty, there are more
- > compact heat exchangers such as plate type exchanger. Also, the
- > absence of hairpin bends causes shell-and-tube heat exchangers to take
- > up more space than double pipe heat exchangers in some cases.
- >
- > *Maintenance:*
- >
- > Cleaning of tubes is difficult and fouling is always an issue when
- > overall heat transfer coefficient is addressed. This requires periodic
- > cleaning of the shell as well as the tubes. Cleaning tubes may be more
- > difficult if the pitch is triangular.
- >
- > **Utilities**
- >
- > The selection of utilities to be used in the shell and tubes tube
- > exchanger takes into
- >
- > account the type of industry in which it is being operated and the
- > desired parameters, such as the required power, thermal stability and
- > thermal capacity.
- >
- > *Cooling* *Water*:
- >
- > Cooling water is used to cool and/or condense currents. The cooling
- > water circulates inside heat exchangers. About 80% of the temperature
- > reduction is due to the evaporation of the cooling water and the
- > transfer of heat to the surrounding air.
- >
- > *Steam:*
- >
- > Steam is the most common heat utility used in the chemical industry
- > and can be used to power pumps, compressors and heat exchangers. Using
- > steam allows a more efficient heat source since the heat of
- > condensation of the steam is quite high, which translates into a high
- > yield per utility mass, at a constant temperature. Another reason is
- > that steam is non-flammable, non-toxic and inert to various process
- > fluids (more safe than other utilities like oil).
- >
- > **Conclusion**
- >
- > The simple design of a shell and tube heat exchanger makes it an ideal
- > cooling solution for a wide variety of applications and as a
- > consequence shell-and-tube heat exchangers are very popular and
- > commonly found in industrial use.
- >
- > **References**
- >
- > \[1\] Notes on Transfer Phenomena II, Professor Maria Graça Carvalho,
- > 2018/2019;
- >
- > \[2\] Warren D. Seider, University of Pennsylvania
- >
- > \[3\] Heat Transfer by Changel 2nd Edition
- >
- > \[4\] Heat Transfer by Holman 6th Edition
+ <img src="./fa4pc54n.png"
+ style="width:3.085in;height:1.71389in" />
+
+ > Departamento de Engenharia Química
+ >
+ > Mestrado Integrado em Engenharia Química
+ >
+ > Integração e intensificação de processos
+ >
+ > Shell and Tubes Heat Exchangers
+ >
+ > **Docente** **Responsável:**
+ >
+ > Nuno Manuel Clemente de Oliveira
+ >
+ > **Integrantes** **do** **grupo:**
+
+ João Victor Vieira
+
+ > Matteo Gecchele
+
+
+
+ > **Introduction** **&** **Structure**
+ >
+ > The most common type of heat exchanger is the shell-and-tube, usually
+ > used in a lot of industrial applications. This type of heat exchanger
+ > has large number of tubes, sometimes several hundred, packed in a
+ > shell with their axes parallel to that of the shell. The heat transfer
+ > takes place between two fluid, one flowing inside the tubes and one
+ > flowing outside the tubes through the shell. Baffles are commonly
+ > placed in the shell to force the shell-side fluid to flow across the
+ > shell to enhance heat transfer, to maintain uniform spacing between
+ > the tubes and, also in order to maintain the turbulent flow inside the
+ > exchanger. The baffle spacing is usually not greater than a distance
+ > equal to the inside diameter or closer than a distance equal to
+ > one-fifth the inside diameter of the shell.
+ >
+ > Usually the shell-and-tube heat exchangers have large size and weight,
+ > and for this reason they are not using in automotive and aircraft
+ > applications. At both ends of the shell, the tubes open to some large
+ > flow areas, called headers, where the tube-side fluid accumulates
+ > before entering the tubes and after leaving them.
+ >
+ > Shell-and-tube heat exchangers are further classified according to the
+ > number of shell and tube passes involved. Heat exchangers in which all
+ > the tubes make one U-turn in the shell, for example, are called
+ > one-shell-pass and two-tube-passes heat exchangers. Likewise, a heat
+ > exchanger that involves two passes in the shell and four passes in the
+ > tubes is called a two-shell- passes and four-tube-passes heat
+ > exchanger.
+
+ <img src="./tnci3l31.png"
+ style="width:2.85417in;height:1.78125in" /><img src="./cncqllod.png"
+ style="width:2.57292in;height:2.02083in" />
+
+ > **Operation** **principle**
+ >
+ > In order to calculate the temperature difference ∆𝑡 in a 1-2
+ > exchanger, it is necessary to make some assumptions:
+ >
+ > 1\. The shell fluid temperature is an average isothermal temperature
+ > at any cross section
+ >
+ > 2\. There is an equal amount of heating surface in each pass 3. The
+ > overall coefficient of heat transfer is constant
+ >
+ > 4\. The specific heat of each fluid is constant 5. The flowrate of
+ > each fluid is constant
+ >
+ > 6\. There are not phase change (evaporation or condensation) in a part
+ > of the exchanger
+ >
+ > 7\. Heat losses are negligible
+ >
+ > The overall heat balance where ∆𝑡 is the true difference of
+ > temperatures, is:
+ >
+ > 𝑄 = 𝑈𝐴∆𝑡 = 𝑊𝐶(𝑇 − 𝑇 ) = 𝑤𝑐(𝑡2 − 𝑡1) where U is the heat transfer
+ > coefficient and A is the surface of contact.
+ >
+ > Shell-and-tube heat exchangers are complicated devices and the
+ > simplified approaches should be used with care. In fact, it is assumed
+ > that the overall heat transfer coefficient U is constant throughout
+ > the heat exchanger and that the convection heat transfer coefficients
+ > can be predicted using the convection correlations. However, in some
+ > practical application, the predicted value of U can exceed 30 percent.
+ > Thus, it is natural to tend to overdesign the heat exchangers in order
+ > to avoid unpleasant surprises.
+ >
+ > Heat transfer enhancement in heat exchangers is usually accompanied by
+ > increased
+ >
+ > pressure drop, and this causes higher pumping power. Therefore, any
+ > gain from the enhancement in heat transfer should be balanced against
+ > the cost of the accompanying pressure drop. Also, some thought should
+ > be given to which fluid should pass through the tube side and which
+ > through the shell side. Usually, the more viscous fluid is more
+ > suitable for the shell side (larger passage area and lower pressure
+ > drop) and the fluid with the higher pressure for the tube side.
+ >
+ > Usually, it is convenient to relate the equivalent temperature
+ > difference to the log
+ >
+ > mean temperature difference relation for the counter-flow case as
+ >
+ > ∆ 𝑙𝑚 = 𝐹∆ 𝑙𝑚,𝐶𝐹
+
+ where *F* is the correction factor**,** which depends on the geometry of
+ the heat exchanger and the inlet and outlet temperatures of the hot and
+ cold fluid streams. The
+
+ > ∆𝑇𝑚,𝐶𝐹 is the log mean temperature difference for the case of a
+ > counter-flow heat exchanger with the same inlet and outlet
+ > temperatures.
+ >
+ > The correction factor *F* for a shell-and-tube heat exchanger is shown
+ > in the figures below versus two temperature ratios *P* and *R* defined
+ > as
+ >
+ > 𝑡2 − 𝑡1 𝑇 − 𝑡1
+ >
+ > 𝑇 − 𝑇 𝑡2 − 𝑡1
+ >
+ > where the subscripts 1 and 2 represent the inlet and outlet*,*
+ > respectively. Note that for
+ >
+ > a shell-and-tube heat exchanger, *T* and *t* represent the shell-side
+ > and tube-side temperatures, respectively.
+
+ <img src="./gklfx0zi.png"
+ style="width:5.02431in;height:4.35569in" />
+
+ > **Factors** **that** **influence** **performances** *Fouling:*
+ >
+ > The performance of heat exchangers usually deteriorates with time as a
+ > result of accumulation of deposits on heat transfer surfaces. The
+ > layer of deposits represents additional resistance to heat transfer
+ > and this causes a decrease of the rate of heat transfer in a heat
+ > exchanger. The net effect of these accumulations on heat transfer is
+ > represented by a fouling factor, which is a measure of the thermal
+ > resistance introduced by fouling.
+ >
+ > For a shell-and-tube heat exchanger it possible to write the overall
+ > heat transfer relation as
+ >
+ > 𝑈𝐴𝑠 = 𝑈𝐴𝑖 = 𝑈0𝐴0 = 𝑅 = ℎ𝑖𝐴𝑖 + 𝐴𝑖𝑖 + ln⁡𝑈0𝐴0 𝑖) + 𝐴0 + ℎ0𝐴0
+ >
+ > where 𝐴𝑖 = 𝐷𝐿 and 𝐴0 = 𝐷0𝐿 L are the areas of inner and outer
+ > surfaces, and 𝑅,𝑖 and 𝑅,0 are the fouling factors at those surfaces.
+ >
+ > *Heat* *transfer* *rate:*
+ >
+ > The heat transfer rate is the most important parameter of a heat
+ > exchanger. A heat exchanger should be capable of transferring heat at
+ > the specified rate in order to achieve the desired temperature change
+ > of the fluid at the specified mass flow rate.
+ >
+ > *Size* *and* *Weight:*
+ >
+ > The heat exchanger is better if it is smaller and lighter, in
+ > particular, in the automotive and aerospace industries, where size and
+ > weight requirements are most stringent. For this reason,
+ > shell-and-tube heat exchangers cannot be used in this type of
+ > application. Also, a larger heat exchanger normally carries a higher
+ > price tag. The space available for the heat exchanger in some cases
+ > limits the length of the tubes that can be used.
+ >
+ > *Material:*
+ >
+ > The thermal and structural stress effects need not be considered at
+ > pressures below 15 *atm* or temperatures below 150*°C*. But these
+ > effects are major considerations above 70 *atm* or 550*°C* and
+ > seriously limit the acceptable materials of the heat exchanger.
+ >
+ > A temperature difference of 50*°C* or more between the tubes and the
+ > shell will probably pose differential thermal expansion problems and
+ > needs to be considered. In the case of corrosive fluids, we may have
+ > to select expensive corrosion-resistant materials such as stainless
+ > steel or even titanium.
+ >
+ > **Cost**
+ >
+ > The purchase cost of a shell and tube depends on the rear head type
+ > and on the heat transfer
+ >
+ > area (size factor). The relationship between the purchase cost and the
+ > size factor is
+ >
+ > represented in the graph below
+
+ <img src="./s1x5d1ti.png"
+ style="width:4.86667in;height:3.36917in" />
+
+ > Both fluids are usually forced to flow by pumps or fans that consume
+ > electrical power. The annual cost of electricity associated with the
+ > operation of the pumps and fans can be determined from
+ >
+ > 𝑂𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔⁡𝐶𝑜𝑠𝑡 = 𝑃𝑢𝑚𝑝𝑖𝑛𝑔⁡𝑃𝑜𝑤𝑒𝑟⁡\[𝑘𝑊\] × 𝐻𝑜𝑢𝑟𝑠⁡𝑜𝑓⁡𝑂𝑝𝑒𝑟𝑎𝑡𝑖𝑜𝑛⁡\[ℎ\] ×
+ > 𝑃𝑟𝑖𝑐𝑒𝑜𝑓⁡𝐸𝑙𝑒𝑐𝑟𝑖𝑐𝑖𝑡𝑦⁡\[\$ 𝑘𝑊ℎ\]
+ >
+ > where the pumping power is the total electrical power consumed by the
+ > motors of the pumps and fans.
+ >
+ > Minimizing the pressure drop and the mass flow rate of the fluids will
+ > minimize the operating cost of the heat exchanger, but it will
+ > maximize the size of the heat exchanger and thus the initial cost. As
+ > a rule of thumb, doubling the mass flow rate will reduce the initial
+ > cost by half but will increase the pumping power requirements by a
+ > factor of roughly eight. Typically, fluid velocities encountered in
+ > heat exchangers range between 0.7 and 7 m/s for liquids and between 3
+ > and 30 m/s for gases. Low velocities are helpful in avoiding erosion,
+ > tube vibrations, and noise as well as pressure drop.
+ >
+ > **Advantages**:
+ >
+ > *Size:*
+ >
+ > Shell-and-tube heat exchangers are capable of providing a larger
+ > surface area for heat transfer to take place while having a shorter
+ > length overall due to presence of multiple tubes.
+ >
+ > *Heat* *duty:*
+ >
+ > Shell-and-tube heat exchangers can handle higher temperatures and
+ > pressures and hence higher heat duty. This is because besides
+ > providing a higher overall heat transfer coefficient, additions can
+ > also be made to negate thermal expansion effects and the thickness can
+ > also be varied (more in the next point).
+ >
+ > *Versatility:*
+ >
+ > From the design point of view, shell-and-tube heat exchangers are the
+ > most versatile of all heat exchangers. Being tubular in shape, heads /
+ > closures of required shape and thickness can be used. The number of
+ > tubes and tube pitch can be selected according to operating
+ > conditions. Expansion bellows can be used to negate thermal expansion
+ > effects, baffles if different cuts and spacings can be used to
+ > influence the overall heat transfer coefficients and there's even
+ > something called a floating head which can be added to negate thermal
+ > expansion of the tubes. The number of passes on shell side and tube
+ > side can be altered as well.
+ >
+ > **Disadvantages**:
+ >
+ > *Size:*
+ >
+ > This can also be a disadvantage as at lower heat duty, there are more
+ > compact heat exchangers such as plate type exchanger. Also, the
+ > absence of hairpin bends causes shell-and-tube heat exchangers to take
+ > up more space than double pipe heat exchangers in some cases.
+ >
+ > *Maintenance:*
+ >
+ > Cleaning of tubes is difficult and fouling is always an issue when
+ > overall heat transfer coefficient is addressed. This requires periodic
+ > cleaning of the shell as well as the tubes. Cleaning tubes may be more
+ > difficult if the pitch is triangular.
+ >
+ > **Utilities**
+ >
+ > The selection of utilities to be used in the shell and tubes tube
+ > exchanger takes into
+ >
+ > account the type of industry in which it is being operated and the
+ > desired parameters, such as the required power, thermal stability and
+ > thermal capacity.
+ >
+ > *Cooling* *Water*:
+ >
+ > Cooling water is used to cool and/or condense currents. The cooling
+ > water circulates inside heat exchangers. About 80% of the temperature
+ > reduction is due to the evaporation of the cooling water and the
+ > transfer of heat to the surrounding air.
+ >
+ > *Steam:*
+ >
+ > Steam is the most common heat utility used in the chemical industry
+ > and can be used to power pumps, compressors and heat exchangers. Using
+ > steam allows a more efficient heat source since the heat of
+ > condensation of the steam is quite high, which translates into a high
+ > yield per utility mass, at a constant temperature. Another reason is
+ > that steam is non-flammable, non-toxic and inert to various process
+ > fluids (more safe than other utilities like oil).
+ >
+ > **Conclusion**
+ >
+ > The simple design of a shell and tube heat exchanger makes it an ideal![](./xvze01o4.png)
+
+ > cooling solution for a wide variety of applications and as a
+ > consequence shell-and-tube heat exchangers are very popular and
+ > commonly found in industrial use.
+ >
+ > **References**
+ >
+ > \[1\] Notes on Transfer Phenomena II, Professor Maria Graça Carvalho,
+ > 2018/2019;
+ >
+ > \[2\] Warren D. Seider, University of Pennsylvania
+ >
+ > \[3\] Heat Transfer by Changel 2nd Edition
+ >
+ > \[4\] Heat Transfer by Holman 6th Edition
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