Continuous spiral baffle heat exchanger

Abstract

A continuous helical baffle heat exchanger includes a series of continuous helical members and a plurality of heating elements including a flow guide and a resistive heating element. The flow guide defines a continuous geometric helix disposed about the longitudinal axis and defines a perforation extending in the longitudinal direction through a first longitudinal length of the geometric helix. The first longitudinal length is less than the full longitudinal length of the geometric helix. A resistive heating element extends through the perforation. For each resistive heating element, the length of the resistive heating element and the pitch of the geometric helicoid at the distal end of the resistive heating element are arranged such that the distance of the distal end of the resistive heating element from the geometric helicoid at the distal end of the resistive heating element is X. The distance X is less than or equal to 40% of the pitch of the geometric helicoids at the distal end of the resistive heating element.

Description

Technical Field

[0001] The utility model generally relates to a heating device.

[0002] More specifically, the present invention relates to a heat exchanger for heating a fluid. Background Art

[0003] The contents of this section merely provide background information related to the present disclosure and do not constitute prior art.

[0004] A heat exchanger generally comprises a tubular container and a plurality of heating elements disposed within the tubular container. A working fluid enters the tubular container at one longitudinal end and leaves the tubular container at another longitudinal end. As the working fluid flows within the tubular container, the working fluid is heated by the plurality of heating elements. In a fluid-to-fluid heat exchanger, the heating element is a tube through which the heating fluid flows. Heat is transferred from the heating fluid to the working fluid through the tube wall. In an electric heat exchanger, the heating element is an electric heating element (e.g., a resistance heating element).

[0005] In order to heat the working fluid more quickly and efficiently, a typical heat exchanger increases the total heat exchange area or increases the heat flux of the heating element to increase the heat output. However, the typical method of increasing the total heat exchange area takes up more space in the heat exchanger that can be used to accommodate the working fluid, and the typical method of increasing the heat flux of the heating element may be limited by the material and design of the heating element, as well as other application-specific requirements. Utility Model Content

[0006] In one form, a heater assembly is provided that includes a series of continuous spiral members and a plurality of heating elements. Each spiral member defines opposing edges and a predetermined pattern of perforations extending through each spiral member and parallel to the longitudinal axis of the heater assembly. The plurality of heating elements extend through the perforations of the continuous series of spiral members (and in one form extend through all perforations). The series of continuous spiral members defines a geometric helix.

[0007] In another form, the electric heat exchanger includes a body defining a cavity, a heater assembly disposed in the cavity, and a proximal flange configured to fix the heater assembly to the body. The heater assembly defines a longitudinal axis and includes a series of continuous spiral members and a plurality of heating elements. Each spiral member defines an opposing edge and a perforation extending through each spiral member and parallel to a predetermined pattern of the longitudinal axis. A plurality of heating elements extend through the perforations of a continuous series of spiral members. A series of continuous spiral members defines a geometric helix.

[0008] In yet another form, in an electric heat exchanger, a device provides a consistent linear temperature rise along the length of the electric heat exchanger. The device includes a series of continuous spiral members. Each spiral member defines opposing edges and a predetermined pattern of perforations extending through each spiral member and parallel to the longitudinal axis of the electric heat exchanger. The continuous series of spiral members defines a geometric helix and the perforations are configured to receive a heating element.

[0009] In one form, the heater assembly includes a series of continuous perforated spiral members and a plurality of heating elements. The perforated spiral members cooperate to define a geometric spiral arranged around the longitudinal axis of the heater assembly. Each perforated spiral member defines opposing edges and a predetermined perforation pattern. The perforations extend through each perforated spiral member parallel to the longitudinal axis. The heating element extends through the perforations.

[0010] According to another form, each heating element includes a first section, a second section, and a bend connecting the first section and the second section. The first section extends through a first set of perforations. The second section extends through a second set of perforations. The second set of perforations is parallel to and offset from the first set of perforations.

[0011] According to a further form, the plurality of heating elements are arranged in a concentric pattern.

[0012] According to yet another form, the heater assembly further includes a central support member. Each perforated spiral member defines a central aperture and the central support member extends through the central aperture.

[0013] According to another form, the heater assembly further includes a temperature sensor extending through the interior of the central support member, the temperature sensor including a probe external to the central support member.

[0014] According to another form, the heater assembly further comprises a proximal flange configured to secure the heater assembly to the heat exchanger body. The flange defines a plurality of flange holes and a central recess. The flange holes are aligned with the perforations of the perforated spiral member. The heating element extends through the flange holes. The central support is received in the central recess.

[0015] According to another form, the heater assembly further includes a vent hole providing fluid communication between an exterior of the central support member and an interior of the central support member proximate the flange.

[0016] According to another form, the central support member includes at least one additional heater.

[0017] According to another form, the heater assembly further comprises an unperforated helical member disposed at a distal end of the continuous series of perforated helical members, the unperforated helical member forming an extension of the geometric helix.

[0018] According to another form, each heating element is secured to at least a portion of each aperture through which each heating element extends.

[0019] According to another form, the opposing edges of one helical member overlap the opposing edges of an adjacent helical member.

[0020] According to another form, the opposing edges of one helical member are spaced apart from the opposing edges of an adjacent helical member and connected thereto by a bridging member.

[0021] According to another form, the heater assembly further comprises a plurality of rods extending parallel to the longitudinal axis. The periphery of each perforated spiral member defines a plurality of grooves, and the rods are at least partially disposed within a respective set of grooves.

[0022] According to another form, the rod extends outwardly from the groove beyond the periphery of each perforated spiral member.The heater assembly is configured to be received within a cylindrical cavity of the body, and the rod is configured to provide sliding contact with a wall of the body defining the cylindrical cavity.

[0023] According to another form, the heater assembly further includes a shroud disposed about the at least one perforated spiral member and coupled to the rod.

[0024] According to another form, the rod does not extend outwardly beyond the periphery of each perforated helical member.

[0025] According to another form, the shield is a heat shield configured to reflect radiant energy radially inwardly relative to the longitudinal axis.

[0026] According to another form, the shroud includes at least one skirt defining a plurality of deformable vanes extending radially outwardly relative to the longitudinal axis.

[0027] According to another form, the at least one skirt is disposed proximate a proximal end or a distal end of the heater assembly.

[0028] According to another form, the at least one skirt includes a first skirt and a second skirt. The first skirt is disposed at a proximal end of the heater assembly and the second skirt is disposed at a distal end of the heater assembly.

[0029] According to another form, the continuous series of perforated spiral members defines a variable pitch.

[0030] According to another form, the continuous series of perforated spiral members has a longer pitch near the inlet end of the heater assembly than near the outlet end of the heater assembly.

[0031] According to another form, the heating element is a resistive heating element.

[0032] According to another form, the resistive heating element is one of the following group: a tubular heater, a cartridge heater or a multi-unit heater.

[0033] According to another form, the plurality of heating elements includes a first heating element and a second heating element, the first heating element having a different length than the second heating element.

[0034] According to another form, the heater assembly further comprises an alignment plate coaxially disposed about the longitudinal axis. The alignment plate defines a plurality of plate holes aligned with the perforations of the perforated spiral member.

[0035] In another form, the heat exchanger includes a body, a heater assembly and a proximal flange. The body defines a cylindrical cavity. The heater assembly defines a longitudinal axis. The heater assembly includes a series of continuous perforated spiral members and a plurality of heating elements. The perforated spiral members are arranged in the cylindrical cavity and define a geometric spiral. Each perforated spiral member defines an opposite edge and a predetermined perforation pattern extending through each perforated spiral member and parallel to the longitudinal axis. The heating element extends through the perforations of the perforated spiral member. The proximal flange fixes the heater assembly to the body.

[0036] According to another form, the heat exchanger further comprises a plurality of rods extending longitudinally parallel to the longitudinal axis. The periphery of each perforated spiral member defines a plurality of grooves, and the rods are partially disposed within a respective set of grooves and have a thickness extending radially outward from the periphery of the perforated spiral member so that the rods slidably contact an inner wall of the body defining the cylindrical cavity.

[0037] According to another form, the heat exchanger further comprises a skirt including elastically deformable fins extending radially between the perforated spiral member and an inner wall of the body defining the cylindrical cavity.

[0038] According to another form, the body includes an inlet at the proximal end of the cylindrical cavity and an outlet at the distal end of the cylindrical cavity. The heater assembly also includes an unperforated spiral member connected to the last one in the continuous series of perforated spiral members. The imperforate spiral member forms an extension of the geometric spiral and starts along the geometric spiral at or before the outlet.

[0039] According to another form, the pitch of the imperforate spiral member is equal to the diameter of the outlet.

[0040] In another form, the heater assembly includes a continuous perforated spiral baffle and a plurality of heating elements. The baffle defines a geometric spiral about a longitudinal axis. The perforated spiral baffle defines a predetermined perforation pattern extending through the perforated spiral baffle and parallel to the longitudinal axis. The heating elements extend through the perforations.

[0041] According to a further form, the geometric spiral has a pitch that varies along the longitudinal axis.

[0042] According to another form, the pitch is continuously variable. According to another form, each of the plurality of resistive heating elements comprises a resistive wire, an insulating material, and a sheath, the sheath surrounds the resistive wire, the insulating material is disposed between the resistive wire and the sheath and electrically insulates the resistive wire from the sheath, wherein the sheath comprises a first straight portion, a second straight portion, and a curved portion connecting the distal end of the first straight portion to the distal end of the second straight portion. According to another form, each of the plurality of resistive heating elements comprises a resistive wire, an insulating material, and a sheath, the sheath surrounds the resistive wire, the insulating material is disposed between the resistive wire and the sheath and electrically insulates the resistive wire from the sheath, wherein the sheath comprises a first straight portion, a second straight portion, and a curved portion connecting the distal end of the first straight portion to the distal end of the second straight portion.

[0043] Further areas of applicability will become apparent from the description provided herein.It should be understood that these descriptions and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0045] Figure 1 is a perspective view of a heater assembly constructed in accordance with the teachings of the present disclosure;

[0046] Figure 2 yes Figure 1 A perspective view of a series of continuous spiral members of a heater assembly;

[0047] Figure 3 yes Figure 2 A three-dimensional diagram of a spiral member;

[0048] Figure 4 yes Figure 3 A front view of a spiral member;

[0049] Figure 5 yes Figure 1 A three-dimensional diagram of a series of continuous spiral members and a central support member;

[0050] Figure 6 yes Figure 5 A partial perspective view of a spiral member and a heating element;

[0051] Figure 7 The connection of the heating element to the spiral member is shown;

[0052] Figure 8 yes Figure 1 A partial perspective view of a spiral member and a heating element;

[0053] Fig. 9is a front view of a heating element mounted to a spiral member;

[0054] Fig.10 is a front view of a heating element mounted to a spiral member, showing different arrangements of the heating element;

[0055] Fig.11 yes Figure 1 A partial perspective view of a heater assembly of , wherein the shield is removed to show the non-perforated spiral member and support rod;

[0056] Fig.12 yes Figure 1 A partial perspective view of a heater assembly with a shield and an unperforated spiral member removed;

[0057] Fig.13 yes Figure 1 An enlarged view of part A;

[0058] Fig.14 yes Figure 1 An enlarged view of part B;

[0059] Fig.15 yes Figure 1 A three-dimensional view of the proximal mounting flange;

[0060] Fig.16 is a cutaway perspective view of an electric heat exchanger constructed in accordance with the teachings of the present disclosure;

[0061] Fig.17 yes Fig.16 A cross-sectional front view of an electric heat exchanger;

[0062] Fig.18 It shows that along Figure 1 A diagram of the temperature distribution of a heater assembly;

[0063] Fig.19 The conventional heat exchanger and the Fig.18 a graph of a heating element surface temperature of a heat exchanger of a heater assembly versus distance from a proximal mounting flange;

[0064] Fig. 20 is a left side perspective view of a heater assembly in a second configuration according to the teachings of the present disclosure, shown with an optional shroud installed;

[0065] Fig.21 yes Fig. 20 A right perspective view of the heater assembly of FIG. 1 , showing the optional shroud not installed;

[0066] Fig. 22 yes Fig. 20 a perspective view of a portion of a shield;

[0067] Fig.23 yes Fig. 22 a perspective view of a distal end of a heater assembly;

[0068] Fig.24 yes Fig. 20 A perspective view of a center tube and mounting flange of a heater assembly;

[0069] Fig.25 yes Fig.24 An exploded perspective view of the center tube and mounting flange;

[0070] Fig.26 is a perspective view of a heat exchanger according to the teachings of the present disclosure, comprising Fig. 20 A heater assembly;

[0071] Fig. 27 yes Fig.26 a cross-sectional view of a proximal end of a heat exchanger;

[0072] Fig.28 yes Fig.26 a cross-sectional view of a distal end of a heat exchanger;

[0073] Fig.29 is a perspective view of a heater assembly in a third configuration according to the teachings of the present disclosure showing a straight heating element;

[0074] Fig.30 is a perspective view of an end portion of a heater assembly in a fourth configuration according to the teachings of the present disclosure;

[0075] Fig.31 is a side partial cross-sectional view of an end portion of a heater assembly according to a fifth configuration according to the teachings of the present disclosure;

[0076] Fig.32 yes Fig.31 a side partial cross-sectional view of an opposite end of the heater assembly;

[0077] Fig.33 yes Fig.30 a perspective view of opposite ends of the heater assembly;

[0078] Fig.34 is a perspective view of an end portion of a heater element according to one form of the present disclosure; and

[0079] Fig.35 is a perspective view of an end portion of another form of a heater element according to the present disclosure.

[0080] Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. DETAILED DESCRIPTION

[0081] Detailed Description

[0082] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

[0083] Reference Figure 1 The heater assembly 10 constructed in accordance with the teachings of the present disclosure is configured to be disposed in a heat exchanger 80 ( Fig.16 and 17 1 and 1 . The heater assembly 10 is provided within a tubular body 82 or housing of the heat exchanger 80 to heat the working fluid flowing through the heat exchanger 80. The heater assembly 10 can be mounted to the tubular body 82 of the heat exchanger 80 by a proximal end plate or mounting flange 12. The heater assembly 10 includes a flow guide 14 and a plurality of extending heating elements 16. The heater assembly 10 defines a proximal end 20 and a distal end 21, and the proximal end 20 and the distal end 21 define a longitudinal axis X of the heater assembly 10. The mounting flange 12 is disposed at the proximal end 20 of the heater assembly 10. The plurality of heating elements 16 extend along the longitudinal axis X of the heater assembly 10.

[0084] Reference Figure 2 , the flow guide device 14 includes a plurality of perforated spiral members 18 or spiral baffles, which are connected in a linear array along the longitudinal axis X of the heater assembly 10 to define a continuous geometric spiral. The continuous geometric spiral is such that each perforated spiral member 18 defines a surface that follows a spiral path around the longitudinal axis X. Optionally, the flow guide device 14 also includes a spiral end baffle or an unperforated spiral member 23, which is disposed adjacent to the distal end 21 of the heater assembly 10 and connected to an adjacent perforated spiral member 18 to form an extension of the continuous geometric spiral. The plurality of perforated spiral members 18 and the unperforated spiral members 23 define a continuous spiral flow guide channel 22 to guide the working fluid to flow therein and generate a spiral flow within the tubular body 82 of the heat exchanger 80 ( Fig.16 and 17 ).

[0085] refer to Figure 3 and Figure 4 , each perforated spiral member 18 is in the form of a metal sheet that is bent to form a complete spiral turn. Although not shown in the drawings, it should be understood that the metal sheet can be bent to form only a portion of a spiral turn or more than one turn. The perforated spiral members 18 each define opposing edges 26 and 28 and a predetermined pattern of perforations 30 extending through each perforated spiral member 18. The opposing edges 26 or 28 from one perforated spiral member 18 can be welded to the opposing edges 28 or 26 of an adjacent perforated spiral member 18. In one form, as shown Figure 8 As shown, the opposing edges 26 or 28 of one perforated spiral member 18 may overlap the opposing edges 28 or 26 of an adjacent perforated spiral member 18. Figure 8As shown, the overlap is approximately equal to 1.01 rotations to provide additional coverage. In another form, as Figure 6 As shown, the opposite edge 26 or 28 of one perforated spiral member 18 may abut or be welded to the opposite edge 28 or 26 of an adjacent perforated spiral member 18, so that the surfaces of adjacent perforated spiral members 18 form a continuous surface. In another example not specifically shown, the opposite edge 26 or 28 of one perforated spiral member 18 may be connected to the opposite edge 28 or 26 of an adjacent perforated spiral member 18 by a bridging member (not shown). The bridging member may be spiral shaped or may be another shape, such as extending a short distance in a circular manner.

[0086] Thus, the perforated spiral members 18 are connected along the longitudinal axis X of the heater assembly 10 to form a linear array (continuous series) of perforated spiral members 18. The perforations 30 in the plurality of perforated spiral members 18 are aligned along a direction parallel to the longitudinal axis X of the heater assembly 10, or perpendicular to a radial direction, resulting in an angle relative to each face of the perforated spiral member 18. The non-perforated spiral member 23 is connected to the distal end of a series of continuous perforated spiral members 18. The non-perforated spiral member 23 is similar in structure to the perforated spiral member 18, but has no perforations.

[0087] Each of the perforated spiral member 18 and the unperforated spiral member 23 has an inner peripheral edge 32, and the contour of the inner peripheral edge 32 is such that when viewed in a direction parallel to the longitudinal axis X of the heater assembly 10, the inner peripheral edge 32 defines a circular hole 34 coaxial with the longitudinal axis X. In the example provided, the perforated spiral members 18 each define a plurality of circumferential grooves 36 along the periphery of the perforated spiral member 18. Similarly, the unperforated spiral member 23 defines a plurality of circumferential grooves 36 along its periphery. The circumferential grooves 36 of the plurality of perforated spiral members 18 (and the unperforated spiral member 23) are also aligned in a direction parallel to the longitudinal axis X of the heater assembly 10.

[0088] The pitch, the outer diameter of the perforated spiral member 18, the diameter of the central hole 34 of the perforated spiral member 18, and the thickness of the perforated spiral member 18 can be appropriately selected according to the desired flow rate and the desired flow rate of the working fluid. The number of heating elements 16 and the number of perforations 30 in the perforated spiral member 18 can be appropriately selected according to the desired heat output and thermal efficiency.

[0089] Reference Figure 5The heater assembly 10 also includes a central support member 40, which extends through the central hole 34 of the perforated spiral member 18 and the unperforated spiral member 23, so that a plurality of perforated spiral members 18 and the unperforated spiral member 32 are connected together to provide structural support for the heater assembly 10. The central support member 40 and the unperforated spiral member 23 can also be configured to provide additional heating to the working fluid. In one form, the central support member 40 is an additional heating element (e.g., an electric heating element). When also used as an additional heating element, the central support member 40 may include one or more resistive heating elements, such as a cartridge heater, a tubular heater, or any conventional heater with an elongated structure to provide heating and structural support.

[0090] Reference Figure 6 and 7 , a plurality of heating elements 16 are inserted through the through holes 30. For clarity of illustration, Figure 6 and 7 Only one pair of heating elements 16 is shown, but when fully assembled, all of the through-holes 30 receive the heating elements 16 therethrough, so that the fluid travels along the spiral flow guide channel 22 without passing through the through-holes 30. In the example provided, each of the plurality of heating elements 16 has a clamp-like configuration and includes a pair of straight portions 42 extending through the through-holes 30 of the perforated spiral member 18 and a curved portion 44 connecting the pair of straight portions 42. The heating element 16 may be any suitable type of heating element, such as a resistive heating element.

[0091] For example, electric tubular heaters, electric cartridge heaters, or multi-unit heaters may be used. When the heating elements 16 are electric heating elements, they may include resistive heating elements (e.g., heating coils, not specifically shown) that may be disposed within the straight portions 42 and the curved portions 44 (when included). In the example provided, the resistive heating coils may extend through the straight portions 42 and the curved portions 44 and have opposing leads (not specifically shown) extending from the proximal ends of the respective straight portions 42. Fig.29 , shows one example of a cartridge heater. In this example, the heating element includes only straight portions 42. Each straight portion 42 terminates at a distal end and the heating element 16 is not bent to connect to two of the straight portions 42. Instead, a resistive heating element (not shown) is disposed in each straight portion 42 and an electrical lead extends from the proximal end of each straight portion 42.

[0092] Back to Figure 6 and Figure 7 Each heating element 16 is fixed to at least a portion of each through-hole 30 through which each heating element 16 extends. In the example provided, the heating element 16 is fixed by welding on approximately half of the periphery of each through-hole 30, so that a weld joint 46 is formed along half of the periphery of the through-hole 30.

[0093] Reference Figure 8 , the working fluid is guided by the perforated spiral member 18 in the guide channel 22 to flow in the spiral direction F, and is continuously heated by the heating element 16. By using the guide channel 22, the working fluid can be guided to flow laterally across the heating surface of the heating element 16. Therefore, the working fluid can be more efficiently heated by the heating element 16 within a predetermined length of the heat exchanger 80, which is different from a typical heat exchanger (not shown, in which the working fluid flows in a direction parallel to the longitudinal axis X of the heat exchanger). Since the working fluid is properly guided to flow laterally across the heating surface of the heating element 16, dead zones where the working fluid is not heated can be avoided. In conventional heat exchangers (not specifically shown), dead zones may cause scaling, in which the working fluid decomposes and causes material to accumulate and deposit on the heating element. Therefore, the heat exchanger taught by the present invention can be heated by increasing flow uniformity and reducing the amount of material deposited on the shell or container (for example, Fig.16 and 17 The radiant heat loss of the main body 82 shown in FIG. 8 is used to reduce fouling and increase heat transfer efficiency.

[0094] Reference Fig. 9 and Fig.10 , the heating element 16 can be inserted into the perforation 30 in such a manner that the curved portion 44 of the heating element 16 forms a concentric pattern around the central support member 40 ( Fig. 9 ), or forming a pattern symmetrical with respect to the diameter of the perforated spiral member 18 ( Fig.10 ).exist Fig. 9 and Fig.10 Between the configurations shown, a greater density of heating elements 16 can be installed in the same space using a concentric pattern, but other configurations and patterns can also be used. Fig. 9 and Fig.10 Between the configurations shown, the concentric pattern generally has a tighter bend radius connecting the straight portions 42. Thus, the pattern may also be selected based on design criteria such as component density or bend radius. Fig.12 As shown, the heating elements 16 may have different lengths, so that some heating elements 16 extend further along the longitudinal axis X than other heating elements. The lengths of the heating elements 16 may be based on their positions relative to the non-perforated spiral member 23. In one configuration, one or more heating elements 16 may be a first group of heating elements all having a first length, and one or more different heating elements 16 may be a second group of heating elements all having a second length different from the first length. In this example, the heating elements 16 are not limited to only two groups having two lengths, and may include additional groups and lengths.

[0095] In one configuration, as shown in FIG. Fig.30As shown, heater 510 includes four groups 514, 516, 518 and 520 of heating elements 16, but more or fewer groups may be used. Heater 510 is similar to heater 10 unless otherwise shown or described herein. Accordingly, like numbers represent like features, and their details are not repeated here. Thus, heater 510 includes a guide 524 that defines a continuous geometric spiral disposed around a longitudinal axis 528 of the heater assembly.

[0096] The flow guide 524 defines a predetermined pattern of perforations 30 extending through a first longitudinal length of the geometric spiral in a longitudinal direction 530, the longitudinal direction 530 being parallel to the longitudinal axis 528. The first longitudinal length is less than the entire longitudinal length of the geometric spiral of the flow guide 524 such that the distal end of the geometric spiral is free of perforations 30.

[0097] Flow guide 524 may alternatively be comprised of a single perforated helical member (similar to perforated helical member 18 ) and one or more non-perforated helical members (similar to non-perforated helical member 23 ) arranged and connected as discussed above with reference to perforated helical members 18 and non-perforated helical members 23 .

[0098] Each heating element 16 in a particular group 514, 516, 518, or 520 has the same length as the other heating elements 16 in the group 514, 516, 518, or 520. In other words, each heating element 16 in a particular group 514, 516, 518, 520 terminates at a distance of 100 mm from the flange 12 ( Figure 1 ) at the same distance.

[0099] In the example provided, each set 514, 516, 518, 520 of heating elements 16 has straight portions 42 connected at their distal ends by curved portions 44. In an alternative configuration not specifically shown, each set 514, 516, 518, 520 of heating elements 16 has straight portions 42. Each set 514, 516, 518, 520 may have only straight portions 42 terminating in a closed distal end, similar to Fig.29 Or the closed end 314 shown in 31.

[0100] Return to Fig.30 In the example provided, each group 514, 516, 518, 520 has the same or approximately the same number of heating elements 16. For example, the number of heating elements 16 of the groups 514, 516, 518, 520 may differ by plus or minus five heating elements. Thus, in the example provided, each group 514, 516, 518, 520 is or is approximately one quadrant of the total arrangement of heating elements 16 disposed about the longitudinal axis 528.

[0101] For each resistive heating element 16, the length of the resistive heating element 16 and the pitch of the geometric spiral at the distal end of the resistive heating element 16 are such that the distal end of the resistive heating element 16 is a distance X of the geometric spiral at the distal end of the resistive heating element, wherein the distance X is in the longitudinal direction. The distance X must be sufficient to account for thermal expansion. In one form, the distance X is at least 0.5 inches (12.7 mm). In one form, the distance X is less than or equal to 40% of the pitch of the geometric spiral at the distal end of the resistive heating element. In another form, the distance X is less than or equal to 10% of the longitudinal distance between the last perforated spiral baffle 18 and the unperforated spiral baffle 23.

[0102] The distal end of group 520 of resistive heating elements 16 is disposed further along the spiral flow path than the distal end of group 518, which is disposed further along the spiral flow path than the distal end of group 516 of resistive heating elements, which is disposed further along the spiral flow path than the distal end of group 514. In other words, group 520 of resistive heating elements 16 extends further in the longitudinal direction 530 than group 518, which extends further in the longitudinal direction 530 than group 516, which extends further in the longitudinal direction 530 than group 514.

[0103] In the example provided, the tubular body 82 includes an inlet / outlet 86 (eg, a first end portion of the tubular body) that opens into the interior of the tubular body 82. Fig.16 , Fig.17 , Fig.26 and Fig. 27 530 ), and an inlet / outlet 88 at a second end of the tubular body that opens into the interior of the tubular body 82, which is further in the longitudinal direction 530 than the inlet / outlet 86. The different groups 514, 516, 518, 520 of resistive heating elements 16 are arranged so that the groups 514, 516, 518, 520 extend progressively further in the longitudinal direction 530 and increase in position along the spiral flow path defined by the flow guide 524 within the tubular body 82.

[0104] In the example provided, the group 520 overlaps the inlet / outlet 88 in the longitudinal direction 530. In one form, the group 514 of the resistive heating elements 16 does not overlap the inlet / outlet 88 in the longitudinal direction 530. In one form, the group 516 of the resistive heating elements 16 does not overlap the inlet / outlet 88 in the longitudinal direction 530. In one form, the group 518 of the resistive heating elements 16 does not overlap the inlet / outlet 88 in the longitudinal direction 530.

[0105] In an alternative form not specifically shown, the group 520 may terminate before the inlet / outlet 88 such that the group 520 does not overlap with the inlet / outlet 88 in the longitudinal direction 530 .

[0106] In the example provided, the non-perforated areas of the flow guide 524 are positioned so that none of the resistive heating elements 16 terminate in an area of ​​the spiral flow path that is rotationally beyond the inlet / outlet 88. In other words, none of the resistive heating elements 16 are located in a low pressure area that is formed when a majority of the fluid flow exits the flow guide and flows directly through the inlet / outlet 88, that is, flows rotationally through the inlet / outlet 88 and / or after the inlet / outlet 88, or flows farther in the longitudinal direction 530 than the inlet / outlet 88.

[0107] exist Fig.30 In the example provided in FIG. 5 , flow guide 524 is a right-handed helix such that fluid flows in a counterclockwise direction when viewed from a direction opposite to longitudinal direction 530 (ie, from inlet / outlet 88 toward inlet / outlet 86 ), although a left-handed helix may be used.

[0108] In the example provided, the pitch of the flow guide 524 is similar in length to the diameter of the inlet / outlet 88. Thus, if any resistive heating element 16 is aligned with the inlet / outlet 88 in the longitudinal direction 530, none of the resistive heating elements 16 terminates rotationally further in the direction of flow than 12 o'clock, where the inlet / outlet 88 is located, when viewed from a direction opposite to the longitudinal direction 530. In the example provided, the group 520 of resistive heating elements 16 terminates at approximately 3 o'clock, but other rotational positions may be used.

[0109] Continue to see Fig.30 And add reference Fig.32 As shown, each heating element 16 can have the same overall length. Therefore, the opposite ends 3210 of the heating elements 16 do not all extend the same distance from the mounting flange 12 in a direction opposite to the longitudinal direction 530. In other words, the opposite ends 3210 of the heating elements 16 can be located at different axial positions relative to each other. The axial position of the opposite ends 3210 can be related to the axial position of the end 314. In another configuration, the heating elements 16 can have different overall lengths so that the opposite ends all terminate at the same distance from the mounting flange 12, Figure 1 Similar to the one shown.

[0110] Fig.32 Shows Fig.31 The opposite ends 3210 of each straight heating element 16 are at different positions, and Fig.33 An alternative configuration of the heater is shown at the opposite end 3310, where there is a first set of heating elements 16_a and a second set of heating elements 16_b, similar to Fig.23 and 28Each heating element 16 in the first set of heating elements 16_a has the same overall length as each heating element 16 in the second set of heating elements 16_b, but the opposite end 3310 is located at the bend 44 ( Figure 6 ) or end 314 ( Fig.29 ) at different axial positions corresponding to the axial positions of the axial direction. Although two groups of heating elements 16 are shown, more than two groups of heating elements may also be used. For example, Fig.30 The four sets of heating elements 16 may alternatively have the same overall length, with their opposite ends (not specifically shown) extending different distances from a mounting flange (not specifically shown).

[0111] In the embodiment described herein, a single straight portion 42 (e.g., Fig.29 and 31 ) instead of the bend 44 (eg, Figure 1 and 30 ) configuration, each heating element 16 has a pair of leads or terminals 3410, 3414 ( Fig.34 Each heating element is described herein as having two straight portions 42 (e.g., Figure 1 and 30 ) configuration, the opposite end 3310 of each straight portion 42 includes wires or terminals 3510, 3514 ( Fig.35 ). Accordingly, in a configuration where the opposite ends 3210, 3310 do not all terminate at the same axial position, via a junction box such as 2610 ( Fig.26 The terminals 3410, 3414 or 3510, 3514 within (shown in FIG. 26 ) and the connections to the electrical power are not all located at the same axial position within the terminal box 2610.

[0112] In another configuration, such as Fig.31 As shown, the resistive heating elements 16 are straight and terminate at their distal ends 314, similar to Fig.29 , except that the length of the resistive heating element 16 is such that the distal end 314 closely follows the shape of the unperforated area of ​​the flow guide 524. In other words, the distance X is less than or equal to 10% of the pitch of the geometric spiral at the distal end 314 of any particular resistive heating element 16.

[0113] In one form, the resistive heating elements 16 may all have different lengths. In another form, the resistive heating elements 16 aligned along a radial line (extending radially outward from the longitudinal axis 528) may have the same length to form discrete groups.

[0114] exist Fig.31In the example provided in FIG. 5 , flow guide 524 is a left-handed spiral such that fluid flows in a clockwise direction when viewed from a direction opposite to longitudinal direction 530 (ie, from inlet / outlet 88 toward inlet / outlet 86 ), but a right-handed spiral may be used.

[0115] In the example provided, the pitch of the flow guide 524 is similar in length to the diameter of the inlet / outlet 88. Thus, if any resistive heating element 16 is aligned with the inlet / outlet 88 in the longitudinal direction 530, then no resistive heating element 16 terminates rotationally further in the direction of flow than 12 o'clock, where the inlet / outlet 88 is located, when viewed from a direction opposite the longitudinal direction 530. In the example provided, none of the resistive heating elements 16 terminates rotationally beyond approximately 9 o'clock, but other rotational positions may be used.

[0116] refer to Fig.11 and Fig.12 The heater assembly 10 may further include a plurality of support rods 50 extending through the peripheral grooves 36 of the perforated spiral member 18 and the non-perforated spiral member 23 and parallel to the longitudinal axis X of the heater assembly 10. The support rods 50 may extend outward (i.e., in a radial direction relative to the longitudinal axis X) beyond the periphery of the peripheral grooves 36 and may be configured as sliding rods for mounting the heater assembly 10 into the cylindrical chamber 84 of the tubular body 82 of the heat exchanger 80 ( Fig.16 and 17 In other words, the support rod 50 can reduce the direct surface contact between the heater assembly 10 and the inner wall of the tubular body 82 ( Fig.16 and Fig.17 ), to reduce friction and thereby reduce the force required to slide the heater assembly 10 into the tubular body 82. Alternatively, the support rod 50 may be configured not to extend beyond the periphery of the peripheral groove 36 and serve only as a structural support for supporting the heater assembly 10. In the example provided, the support rod 50 is welded to the perforated spiral member 18 and the non-perforated spiral member 23.

[0117] Returning to 1, the heater assembly 10 may also include a pair of shields 52 disposed at the proximal end 20 and the distal end 21, for surrounding the perforated spiral member 18, the non-perforated spiral member 23, the heating element 16, and the support rod 50. At the proximal end, the shield 52 is generally located between the non-heated portion 54 and the heated portion 56. Although Figure 1 Two shields 52 are shown, but any number of shields 52 (including one) may be provided to surround the perforated spiral member 18, the heating element 16, and the support rod 50. When one shield 52 is provided, the shield 52 may be provided at the distal portion 21 or at the proximal portion 20.

[0118] See also Fig.13 and Fig.14 , the shrouds 52 may each define a cylindrical shroud member 51 and a plurality of deformable fins 53, the deformable fins 53 forming a skirt around the cylindrical shroud member 51. The cylindrical shroud member 51 may wrap around a portion of the perforated and / or non-perforated spiral members 18, 23. In the example provided, each cylindrical shroud member 51 extends a length along the longitudinal axis X that is at least one complete spiral pitch of the corresponding perforated or non-perforated spiral member 18, 23 that it surrounds. The deformable fins 53 are typically formed by cutting a radially outward flange portion of the shroud 52 so that the fins 53 may extend radially outward from the cylindrical shroud member 51. Contact with the inner wall of the tubular body 82 may elastically deform the fins 53 so that the fins 53 are biased into contact with the inner wall of the tubular body 82 to prevent fluid from escaping between the tubular bodies 82 of the heat exchanger 80, thereby reducing blowby. In the example provided, Fig.13 The fins 53 of the distal shroud 52 shown may be axially positioned near the distal end of the heater assembly 10, such as just before the outlet 88 of the tubular body 82 of the heat exchanger 80. For example, the fins 53 of the distal shroud 52 may be positioned approximately before the outlet 88 of the tubular body 82. Fig.17 In the example provided, Fig.14 The fins 53 of the illustrated proximal shroud 52 may be axially positioned near the beginning of the perforated helical member 18, such as after the entrance 86 of the tubular body 82. For example, the fins 53 of the proximal shroud 52 may be positioned approximately 1 / 4 of the length of the tubular body 82 after the entrance 86. Fig.17 The dashed line 94 shown in FIG.

[0119] Reference Fig.15 As shown, the proximal mounting flange 12 is configured to secure the heater assembly 10 to the tubular body 82 of the heat exchanger 80. The proximal mounting flange 12 includes a plate body 58, a plurality of holes 60, and a plurality of bolt holes 62 that pass through the heat exchanger 80. The plurality of holes 60 are aligned with the through-holes 30 of the continuous series of perforated spiral members 18, and are configured to guide the plurality of heating elements 16 through the proximal mounting flange 12. Although not specifically shown, the heating elements 16 can be sealed to the holes 60, thereby preventing fluid from flowing through the holes 60. The plurality of bolt holes 62 are defined along the periphery of the plate body 58. The proximal mounting flange 12 can be secured by inserting bolts (not shown) into the bolt holes 62 and through a mating flange (e.g., Fig.26 The heat exchanger is mounted to the tubular body 82 of the heat exchanger by bolt holes in the mating flange 83 shown. A gasket (not shown) or other sealing material can be used between the mounting flange 12 and the mating flange (e.g., Fig.26The flange 83 shown forms a fluid-tight seal between them. In another configuration not shown, the end plate or mounting flange 12 can be mechanically attached to the mating flange by different means, such as welding, latches, clamps, etc.

[0120] The proximal mounting flange 12 may also define a circular central recess or groove 64 that is configured to align with the central support member 40. The central groove 64 is coaxial with the longitudinal axis X, and the proximal end of the central support member 40 is configured such that the central support member 40 is received in the central groove 64. In the example provided, the central support member 40 is welded to the proximal mounting flange 12.

[0121] refer to Fig.16 and Fig.17 As shown, a heat exchanger 80 configured in accordance with the teachings of the present disclosure includes a tubular body or housing 82 defining a cylindrical cavity 84, an inlet 86, an outlet 88, and a heater assembly 90 disposed within the tubular body 82. The heater assembly 90 defines a proximal end 20 and a distal end 21. The proximal mounting flange 12 is configured to secure the heater assembly 90 to the body 82.

[0122] The heater assembly 90 is similar in structure to Figure 1 The heater assembly is provided with a series of continuous perforated spiral members 18 and unperforated spiral members 23 connected in a manner that the spiral body defined by the perforated spiral members 18 and the unperforated spiral members 23 has a variable pitch. Therefore, similar elements are represented by similar reference numerals, and for the sake of clarity, detailed descriptions thereof are omitted herein. In the example provided, the outlet 88 is a radial outlet so that it is open to the flow path 22 in a radial direction. In an alternative configuration not specifically shown, the outlet 88 can be an axial end outlet opened through the axial end 96 of the main body 82.

[0123] Returning to the example provided, the pitch of the helix defined by the perforated helical member 18 and the non-perforated helical member 23 is greatest at the proximal end 20 (near the inlet 86 of the heat exchanger 80) and smallest at the distal end 21 (near the outlet 88 of the heat exchanger 80). In one form, the pitch is a continuously varying pitch that gradually decreases from the proximal end 20 to the distal end 21. Fig.17As shown, the heater assembly 90 can define multiple regions along the longitudinal axis X of the heater assembly 90. The pitch can be fixed in a specific area, and different areas can have different pitches. For example, the heater assembly 90 can define three heating areas, wherein the first area has a first fixed pitch P1, the second area has a second fixed pitch P2, and the third area has a third fixed pitch P3. The second fixed pitch P2 is greater than the third fixed pitch P3 and less than the first fixed pitch P1. The first pitch P1 is located at the proximal end 20. The third pitch P3 is located at the distal end 21. The second pitch P2 is located between the first pitch P1 and the third pitch P3. Although three areas are shown, more or fewer areas can be used. In one form, each perforated spiral member 18 or a group of perforated spiral members 18 can have a constant pitch along its specific length, and different perforated spiral members 18 or different groups thereof can have different pitches to form a variable pitch geometric spiral.

[0124] In an alternative configuration not specifically shown, the perforated spiral body may not be formed by separate components connected together, but rather by a single continuous spiral member spanning from the proximal end to the distal end of the heater assembly. For example, the single spiral member may be extruded, formed, or 3D printed by feeding a strip of metal through opposing conical dies.

[0125] Reference Fig.18 , the figure shows the temperature distribution of the heating element 16 along the longitudinal axis X for a particular configuration of the heater assembly 10, 90. In the particular example, the temperature of the portion of the heating element 16 adjacent to the proximal portion of the heater assembly is approximately 33.94°C. When the working fluid is guided by the guide channel 22 of the perforated spiral member 18 and flows to the distal end of the heater assembly 10, 90, in the example provided, the temperature gradually increases to approximately 534.92°C. Although Fig.18 The temperature profile is shown for a particular inlet temperature, electrical power load of the heating element 16, and mass flow rate of the fluid, but other temperatures and profiles may result from different conditions or configurations. In general, a heater assembly constructed in accordance with the teachings of the present disclosure will have a reduced heating element temperature without dead zones where the working fluid is not heated along its flow path.

[0126] Reference Fig.19, the figure shows the relationship between the distance from the proximal mounting flange 12 and the temperature of the heating element 16. The proximal mounting flange 12 is disposed near the inlet 86 of the heat exchanger 80. As the working fluid enters the inlet 86 and flows away from the proximal mounting flange 12, the temperature of the outer surface of the heating element 16 increases steadily and gradually, as shown by line 97. In contrast, the outer surface of the heating element of a typical heat exchanger (not shown) has a higher temperature, which also increases and decreases as the fluid flows away from the proximal flange (i.e., from the inlet to the outlet), as shown by line 98. Accordingly, the teachings of the present disclosure provide a heater assembly and heat exchanger that provide a consistent and low linear temperature rise of the heating element along the length of the heat exchanger.

[0127] The heater assembly of the present disclosure can be applied to any heating device (e.g., an electric heating device) to heat a working fluid. A series of continuous perforated spiral members 18 guide the fluid to produce a uniform spiral cross-flow pattern. The spiral channel 22 of the heater assembly 10, 90 can change and increase the flow path of the working fluid without increasing the length of the heater assembly 10, 90. Therefore, the heater assembly 10, 90 can improve the heat transfer from the heater assembly 10, 90 to the working fluid. With the improvement of heat transfer efficiency, the sheath temperature of the heating element 16 and the temperature of the outer shell (e.g., tubular body 82) of the heat exchanger can be reduced, and the physical footprint of the heat exchanger can be reduced.

[0128] In addition, the perforated spiral member 18 can be formed of a thermally conductive material. Since the perforated spiral member 18 can be connected to the heating element 16 (e.g., via Figure 7 The central support member 40 may be formed of a cylindrical electric heating device to provide additional heating to the working fluid in an electric heat exchanger.

[0129] In addition, the heater assembly 10, 90 is more rigid than heater assemblies in conventional heat exchangers due to the use of a continuous series of perforated spiral members 18 and the use of a central support member 40. The central support member 40 is connected to a proximal mounting flange 12, which in turn is connected to the body of the heat exchanger. This continuous structure improves the vibration characteristics of the heat exchanger, thereby increasing the rigidity and damping characteristics of the heater assembly. The support rods 50 can further increase the rigidity and damping characteristics.

[0130] See also Figure 20-25 As shown, the heater assembly 210 is shown, and reference Figure 26-28, a heat exchanger 80 with a heater assembly 210 is shown. The heat exchanger 80 and the heater assembly 210 are similar to the heat exchanger 80 and the heater assembly 10, 90, unless otherwise shown or described herein. Therefore, similar elements are represented by similar reference numerals, and for the sake of clarity, a detailed description thereof is omitted herein.

[0131] Refer to 20 and Fig.21 As shown, the heater assembly 210 may include a first lifting member 214 and a second lifting member 218. The first lifting member 214 is fixedly coupled to the periphery of the mounting flange 12. In the example provided, the first lifting member 214 extends from the top of the mounting flange 12 and defines a hole 222 through which a hook (not shown) or other lifting device can support the proximal end of the heater assembly 210. The second lifting member 218 is fixedly coupled to the distal end of the central support member 40. In the example provided, the second lifting member 218 extends from the top of the central support member 40 and is aligned with the first lifting member 214. The second lifting member 218 defines a hole 226 through which a hook (not shown) or other lifting device can support the distal end of the heater assembly 210. In the example provided, the second lifting member 218 is disposed within the axial length of the non-perforated spiral member 23, although the second lifting member 218 can extend beyond the non-perforated spiral member 23. The first lifting member 214 and the second lifting member 218 may be used to lift the heater assembly 210 and position the heater assembly 210 within the tubular body 82 of the heat exchanger 80 .

[0132] The heater assembly 210 may further include a shield 230. The shield 230 is wrapped around the perforated spiral member 18, the heating element 16, and the support rod 50. The axial length of the shield 230 may extend along the entire length of the heated portion of the heater assembly 210 (e.g., including Figure 1 The shield 52 shown in the figure may be shorter than the entire heated portion. Fig. 22 As shown, the shield 230 may include a plurality of thin-walled cylindrical shield members 234. The shield members 234 may inhibit blowby between the perforated spiral member 18 and the tubular body 82. The shield members 234 may also be formed of a heat reflective material or coated with a heat reflective material to form a heat shield that reflects heat radially inward toward the longitudinal axis X. Such a heat shield may further reduce heat loss from the body 82 and reduce the temperature of the body 82. Adjacent cylindrical shield members 234 may be adjacent to each other along the longitudinal axis X. In one form, any cylindrical shield member 234 of the shield 230 may optionally include a deformable fin 53 ( Fig.13 and Fig.14 ), so that the shield 230 can also function similarly to the shield 52 ( Figure 1 , 13 and 14).

[0133] In the example provided, the support rod 50 has a generally rectangular or cross-sectional shape, and the outer surface 238 of each support rod 50 is flush with the outer perimeter of the perforated and unperforated spiral members 18, 23. In one form, the outer surface 238 of each support rod 50 may have a curvature that matches the outer perimeter curvature of the perforated spiral member 18 and the unperforated spiral member 23. The shield 230 is attached to the support rod 50. In the example provided, the support rod 50 includes a plurality of holes 242 and each cylindrical shield member 234 includes a plurality of holes 246 aligned with the holes 242 of the support rod 50. Fasteners 250 (e.g., rivets, screws, etc.) or plug welds are received through the holes 242, 246 and attach the cylindrical shield member 234 to the support rod 50.

[0134] Additional references Fig.23 As shown, the heater assembly 210 may also include an alignment plate 254. The alignment plate 254 is a flat disk that includes a plurality of holes 256 and a peripheral groove 260. The holes 256 are the same size and aligned with the perforations 30 of the perforated spiral member 18. The size of the peripheral groove 260 is the same size as the peripheral groove 36 and is aligned with the peripheral groove 36. The support rod 50 is received in the peripheral groove 260 similar to the peripheral groove 36. In the example provided, the alignment plate 254 defines a keyed central hole 262 having a diameter similar to the diameter of the central support member 40 and a key 264 extending radially inward. In the example provided, the central support member 40 includes a keyway 266 that passes through the distal end opening of the central support member 40. The keyway 266 extends through the wall of the central support member 40 and extends longitudinally parallel to the longitudinal axis X. The keyway 266 has a width corresponding to the width of the key 264 in the circumferential direction of the central support member 40. The central support member 40 is received through the central hole 262, and the key 264 is received in the keyway 266 to prevent the alignment plate 254 from rotating relative to the central support member 40. In one form, the central hole 262 may include more than one key 264 spaced circumferentially about the central hole 262, and the central support member 40 may include a matching number of keyways 266.

[0135] Continue to refer Fig.23 As shown, the heater assembly 210 may also include one or more sensors (e.g., sensor 300). In the example provided, the sensor 300 is a thermocouple or other temperature sensor, but other types of sensors may also be used. The sensor 300 includes a probe end 306 disposed within the flow channel 22. In the example provided, the probe end 306 is disposed proximate to the outlet 88 ( Fig.26 and 28) and attached (e.g., welded or clamped) to one of the heating element sinks 16. The probe end 306 can be configured to detect the temperature of the heating element 16 to which it is attached. Similarly, additional sensors (not shown) can be attached to other heating elements 16 to detect their temperatures. In an alternative configuration not shown, the probe end 306 can be separated from the heating element 16 and configured to detect the temperature of the working fluid at the probe end 306.

[0136] The sensor 300 extends longitudinally on the outside of the central support member 40 generally along the longitudinal axis X from the probe end 306 to the distal end of the central support member 40. In the example provided, the distal end of the central support member 40 includes a sensor slot 308 that passes through the outer wall of the central support member 40 and is separated from the keyway 266. The sensor 300 has a bend to extend through the sensor slot 308 and into the interior cavity of the central support member 40. The sensor 300 then extends within the central support member 40 toward the proximal end of the central support member 40. Fig.25 As shown, the sensor 300 extends through a hole 318 in the mounting flange 12. The hole 318 is sealed around the sensor 300 to prevent fluid from flowing through the hole 318. The hole 318 is radially inward of the groove 64. In this way, the electronic connections for the sensor 300 can be located on the back side of the mounting flange 12, together with the electrical connections of the heating element 16 when an electric heating element is used.

[0137] In an alternative configuration not shown, a set of aligned through-holes 30 may not have a heating element 16, and a temperature sensor 300 may extend through the set of through-holes 30 and the corresponding flange hole 60. In such a configuration, the probe may be disposed at any desired location along the set of through-holes 30. In an alternative configuration, one or more heating elements 16 may be used as a virtual sensor to detect temperature.

[0138] Additional references Fig.24 and Fig.25 As shown, the vent hole 410 can allow a small amount of fluid communication between the exterior and interior of the proximal end of the central support member 40. In the example provided, the central support member has a slot through the proximal end that cooperates with the mounting flange 12 to define the vent hole 410 when the central support member 40 is received in the groove 64 of the mounting flange 12. Fig.15 The groove 64, Fig.25The groove 64 is an incomplete circle (i.e., does not extend a complete circumference around the longitudinal axis X). Instead, the groove 64 has a starting point 414 and an end 418 that align with the narrow slot in the proximal end of the central support member 40. In the example provided, the groove 64 has a flat bottom that abuts the flat bottom surface of the central support member 40. The starting end 414 and the end 418 also form a key that ensures that the central support member 40 is properly rotated. In the example provided, the key between the central support member 40 and the mounting flange 12 and the alignment plate 254 cooperate to position the continuous spiral in the correct rotational position so that the perforation 30 is aligned with the holes 60 and 256. In the example provided, the key at both ends of the central support member 40 is parallel to the longitudinal axis X, but other configurations can also be used. In the example provided, the groove 64 also extends radially outward for a short distance at the starting point 414 and the end point 418 of the groove 64. In the example provided, the central support member 40 is welded to the mounting flange 12 from the starting point 414 to the end 418 of the groove 64. In other words, the central support member 40 is welded around its circumference except for the circumferential region where the slot defines the vent 410. The vent 410 may be aligned with the top of the mounting flange 12. In another form, the vent 410 may be a hole completely defined by the central support member 40 near the proximal end.

[0139] Specific reference Fig. 27 As shown, the edge 28 (ie, near the proximal end) of the first perforated helical member 18 may be disposed at or before the inlet 86 along the longitudinal axis X such that flow from the inlet enters the flow path 22. Fig.28 As shown, the opposite edge 26 (i.e., near the distal end) of the last perforated spiral member 18 can be disposed at or before the outlet 88 along the longitudinal axis X. In the example provided, the longest of the heating elements 16 extends along the longitudinal axis X to a position partially within the region aligned with the outlet 88, but other configurations can also be used. In the example provided, the last cylindrical shield member 234 can extend along the longitudinal axis X to axially overlap the end of the longest of the heating elements 16 to force the fluid to flow from the last heating element 16 to the non-perforated spiral member 23 before exiting the outlet 88, but other configurations can also be used.

[0140] Additional references Fig.29, a portion of a third configuration of a heater assembly 310 is shown. The heater assembly 310 is similar to the heater assemblies 10, 90, 210 unless otherwise shown or described herein. Therefore, similar elements are represented by similar reference numerals, and detailed descriptions thereof are omitted herein for the sake of clarity. In the example provided, the heating element 16 is a straight element terminating in a closed end 314. In other words, the straight portions 42 are not connected by bends. In the example provided, the heating element 16 is a resistive heating element, such as a cartridge heater, with all leads (not shown) extending from the mounting flange 12 (at Fig.26 The same straight portion 42 extends on the opposite side of the circumference of the drawing (shown in FIG. 1 ).

[0141] It should be noted that the present disclosure is not limited to the embodiments described and shown as examples. A variety of modifications have been described, and more modifications are part of the knowledge of those skilled in the art. These and further modifications and any replacement of technical equivalents may be added to the description and drawings without departing from the scope of protection of the present disclosure and this patent.

Claims

1. A continuous spiral baffle heat exchanger, characterized in that: include: a flow guide defining a continuous geometric spiral disposed about a longitudinal axis of the continuous spiral baffle heat exchanger, the flow guide defining a plurality of perforations in a predetermined pattern, the plurality of perforations extending in a longitudinal direction through a first longitudinal length of the geometric spiral, the longitudinal direction being parallel to the longitudinal axis, the first longitudinal length being less than a full longitudinal length of the geometric spiral; and a plurality of resistive heating elements extending through the plurality of through-holes, Wherein, for each of the multiple resistive heating elements, the length of the resistive heating element and the pitch of the geometric spiral at the distal end of the resistive heating element are set so that the distance between the distal end of the resistive heating element and the geometric spiral at the distal end of the resistive heating element is X, wherein the distance X refers to the distance along the longitudinal direction, and the distance X is less than or equal to 40% of the pitch of the geometric spiral at the distal end of the resistive heating element.

2. The continuous spiral baffle heat exchanger according to claim 1, characterized in that: The plurality of resistance heating elements include a plurality of different groups of resistance heating elements, and the length of each group of resistance heating elements extending along the longitudinal direction is different from the length of other resistance heating elements extending along the longitudinal direction.

3. The continuous spiral baffle heat exchanger according to claim 2, characterized in that: The multiple groups of different resistive heating elements include a first group of resistive heating elements, a second group of resistive heating elements, a third group of resistive heating elements and a fourth group of resistive heating elements, wherein the first group of resistive heating elements, the second group of resistive heating elements, the third group of resistive heating elements and the fourth group of resistive heating elements are each located in a corresponding quadrant about the longitudinal axis.

4. The continuous spiral baffle heat exchanger according to claim 3 is characterized in that: The first group of resistive heating elements, the second group of resistive heating elements, the third group of resistive heating elements, and the fourth group of resistive heating elements all have the same number of heating elements.

5. The continuous spiral baffle heat exchanger according to claim 3, characterized in that: The fourth group of resistive heating elements extends further in the longitudinal direction than the third group of resistive heating elements, the third group of resistive heating elements extends further in the longitudinal direction than the second group of resistive heating elements, and the second group of resistive heating elements extends further in the longitudinal direction than the first group of resistive heating elements.

6. The continuous spiral baffle heat exchanger according to claim 5, characterized in that include: a tubular body comprising a first inlet / outlet opening into the interior of the tubular body at a first end of the tubular body and a second inlet / outlet opening into the interior of the tubular body at a second end of the tubular body, Wherein, the guide portion is arranged in the tubular body, and The fourth group of resistance heating elements overlaps with the second inlet / outlet in the longitudinal direction, and the first group of resistance heating elements does not overlap with the second inlet / outlet in the longitudinal direction.

7. The continuous spiral baffle heat exchanger according to claim 6, characterized in that: The second set of resistive heating elements does not overlap the second inlet / outlet in the longitudinal direction.

8. The continuous spiral baffle heat exchanger according to claim 7, characterized in that: The third set of resistive heating elements does not overlap the second inlet / outlet in the longitudinal direction.

9. The continuous spiral baffle heat exchanger according to any one of claims 2 to 8, characterized in that include: a tubular body comprising a first inlet / outlet opening into the interior of the tubular body at a first end of the tubular body and a second inlet / outlet opening into the interior of the tubular body at a second end of the tubular body, wherein the flow guide is arranged in the tubular body so that the geometric spiral and the tubular body define a spiral flow path between the first inlet / outlet and the second inlet / outlet, and Wherein, the multiple groups of different resistance heating elements are arranged such that different groups of resistance heating elements gradually extend farther in the longitudinal direction as the position along the spiral flow path increases.

10. The continuous spiral baffle heat exchanger according to any one of claims 1 to 8, characterized in that: Each of the plurality of resistive heating elements comprises a resistive wire, an insulating material and a sheath, wherein the sheath surrounds the resistive wire, the insulating material is disposed between the resistive wire and the sheath and electrically insulates the resistive wire from the sheath, wherein the sheath comprises a first straight portion, a second straight portion and a curved portion connecting a distal end of the first straight portion to a distal end of the second straight portion.

11. The continuous spiral baffle heat exchanger according to any one of claims 1 to 8, characterized in that: Each of the plurality of resistive heating elements includes a resistive wire, an insulating material and a sheath, the sheath surrounding the resistive wire, the insulating material being disposed between the resistive wire and the sheath and electrically insulating the resistive wire from the sheath, wherein the sheath includes a straight portion terminating at a distal end of the resistive heating element.

12. The continuous spiral baffle heat exchanger according to any one of claims 1 to 8, characterized in that: The distance X is less than or equal to 10% of the pitch of the geometric helix at the distal end of the resistive heating element.

13. The continuous spiral baffle heat exchanger according to any one of claims 1 to 8, characterized in that include: a tubular body comprising a first inlet / outlet opening into the interior of the tubular body at a first end of the tubular body and a second inlet / outlet opening into the interior of the tubular body at a second end of the tubular body, wherein the flow guide is arranged in the tubular body such that the geometric spiral and the tubular body define a spiral path between a first inlet / outlet and a second inlet / outlet, wherein the second inlet / outlet is further in the longitudinal direction than the first inlet / outlet, and Wherein none of the plurality of resistive heating elements terminates in a region rotationally beyond the helical path of the second inlet / outlet.

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