US20160018131A1

US20160018131A1 - Venturi disk non-exposed flame and electronic controls heater

Info

Publication number: US20160018131A1
Application number: US14/773,205
Authority: US
Inventors: Christopher J. MESO; Mark P. Henry
Original assignee: MOBILE AIR Inc
Current assignee: Mobile Air LLC
Priority date: 2013-03-15
Filing date: 2014-03-14
Publication date: 2016-01-21
Also published as: CA2903884A1; WO2014143976A1

Abstract

A portable heating apparatus includes a housing, a heat source, a fan, and a heat shield. The housing includes a fluid inlet and a fluid outlet. The fluid inlet is in fluid communication with the fluid outlet. The heat source is located within the housing. The fan creates a flow of fluid from the inlet to the outlet and is disposed between the heat source and the outlet. The heat shield is disposed between the heat source and the fan and is operable to restrict the flow of fluid between the heat source and the fan.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application the benefit of U.S. Provisional Application No. 61/798,611, filed on Mar. 15, 2013. The entire disclosure of the above application is incorporated herein by reference.

FIELD

The present disclosure relates to mobile or otherwise portable heater, and more particularly to a portable heater including a non-exposed burner and flame.

BACKGROUND

This section provides background information related to the present disclosure which is not necessarily prior art.
Portable heaters are often used to provide heat to building or facility. Such heaters may be utilized as a main heat source or a supplemental heat source. For example, when constructing or renovating a building, it may be desirable to heat the facility with a portable heat source before, during or after construction of the building's permanent heat source has begun. In such situations, it may be desirable to provide a sufficient amount of heat, while also controlling the level of humidity in the heated space, and reducing the risk of fire in and around the heated space.
Many portable heaters utilize an open flame or burner. In an open flame system, a fan or blower, located upstream of the burner, may pull air through an inlet, and push the air over or through the burner and through an outlet to heat the space. In such a system, the flame may be visible or otherwise exposed through both the inlet and the outlet. In some situations, it may be desirable to enclose the flame, or otherwise prevent the flame from being visible or otherwise exposed, in order to reduce the risk of fire in and around the heated space. However, enclosing the burner or flame may produce other undesirable results. For example, in some closed flame systems, the fan may be located downstream of the burner. In a closed flame system, the fan or blower may be located downstream of the burner, and may pull air through the inlet, over or through the burner, and through the outlet. In such a system, the burner and the heated air exiting the burner and entering the fan may damage the fan or otherwise reduce its useful life.
While existing portable heaters have proven suitable for their intended purposes, a continuous need for improvement in the relevant art remains.

SUMMARY

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
According to one particular aspect, a portable heating apparatus is provided. The portable heating apparatus includes a housing, a heat source, a fan, and a heat shield. The housing includes a fluid inlet and a fluid outlet. The fluid inlet is in fluid communication with the fluid outlet. The heat source is located within the housing. The fan creates a flow of fluid from the inlet to the outlet and is disposed between the heat source and the outlet. The heat shield is disposed between the heat source and the fan and is operable to restrict the flow of fluid between the heat source and the fan.
According to another particular aspect, a portable heating apparatus is provided. The portable heating apparatus may include a housing, a heat source, a fan, and a heat shield. The housing may include a fluid inlet and a fluid outlet. The fluid inlet may be in fluid communication with the fluid outlet. The heat source may be disposed within the housing. The fan may create a flow of fluid from the inlet to the outlet and may be disposed between the heat source and the outlet. The heat shield may be disposed between the heat source and the fan and may include a first conical construct having a first apex and a second conical construct having a second apex. The first apex may generally face the heat source and the second apex may generally face the fan.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1 is a perspective view of one configuration of a heater in accordance with the principles of the present disclosure;

FIG. 2 is a schematic cross-sectional view of the heater of FIG. 1, including a heat shield in accordance with the principles of the present disclosure;

FIG. 3A is a perspective view of one configuration of the heat shield of FIG. 1;

FIG. 3B is a perspective view of another configuration of the heat shield of FIG. 1;

FIG. 3C is a perspective view of another configuration of the heat shield of FIG. 1;

FIG. 3D is a perspective view of another configuration of the heat shield of FIG. 1;

FIG. 3E is a perspective view of another configuration of the heat shield of FIG. 1;

FIG. 3F is a perspective view of another configuration of the heat shield of FIG. 1;

FIG. 4A is a front view of the heat shield of FIG. 3A;

FIG. 4B is a front view of the heat shield of FIG. 3B;

FIG. 4C is a front view of the heat shield of FIG. 3F;

FIG. 5 is a cross-sectional view of the heat shield of FIG. 3F.

Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference to the accompanying drawings.
With reference to FIGS. 1 and 2, a heating unit 10 is provided. The heating unit 10 may be a mobile or otherwise portable heater that can be transported from and between different locations, such as buildings or other facilities. In this regard, the heating unit 10 may include a plurality of wheels 11. In one application, the heating unit 10 may be used to provide heat to a building or other heated space (not shown) that is under construction. In this regard, the heating unit 10 may be utilized as the primary heat source for the building, or as a secondary or supplemental heat source for the heated space.
The heating unit 10 may include a frame 12, a control system 14, and a heater 16. The frame 12 may carry or otherwise support the control system 14 and the heater 16. The control system 14 may include multiple sensors, switches, processors, controllers (not shown) and other similar electronics for controlling various characteristics or qualities of the air within the heated space. For example, the sensors may be operable to detect the temperature, humidity, cleanliness (e.g., dust or other particulate concentration), or other various measures of air quality. The switches or other controls may be operable to set and otherwise adjust a desired level of the particular measure, and the processors and controllers may be operable to vary the operation of the heater 16 to achieve the desired level of the particular measure.
The heater 16 may include a shell or housing 20, a heat source 22, a blower or fan 24, and a heat shield 26. The housing 20 may define a fluid flow path 28 extending between an inlet 30 and an outlet 32. The housing 20 may define a substantially cylindrical flow path 28 having a diameter D1 at a first cross-sectional area A1 located upstream of the heat shield 26. The diameter D1 may be between six hundred fifty millimeters and seven hundred seventy millimeters. In one configuration, the diameter D1 of the flow path 28 is substantially equal to seven hundred eleven millimeters. The inlet 30 may be in fluid communication with an air source, such as the exterior environment of the building or an interior environment of the building, such as the heated space. The outlet 32 may be in fluid communication with the interior of the building, including the heated space. A neck portion 34 of the housing 20 may be located between the inlet 30 and the outlet 32. The neck portion 34 may define a second diameter D2 at a second cross-sectional area A2 of the fluid flow path 28. The housing 20 may also define a third diameter D3 at a third cross-sectional area A3 of the fluid flow path 28 located downstream of the heat shield 26. The second cross-sectional area A2 may be smaller than the first and third cross-sectional areas A1, A3. In this regard, the second diameter D2 may be between four hundred fifty millimeters and five hundred fifty millimeters. In one configuration, the diameter D2 is substantially equal to five hundred millimeters.
The heat source 22 may be located within the housing 20. In one configuration, the heat source 22 may be located between the inlet 30 and the neck portion 34. The heat source 22 may be a closed or concealed flame heat source having a burner 36 and a flame operable to produce between one hundred fifty thousand and four million BTU's of heat. In this regard, the heater 16 may include a conduit 37 for transporting fuel from a fuel source (e.g., a fuel tank or fuel supply line) to the burner 36.
The fan 24 may be located within the housing 20 and may be operable to pull air through the inlet 30, over the heat source 22, and through the fluid flow path 28, such that the fan 24 provides heated air to the heated space from the outlet 32. In this regard, the fan 24 may be operable to provide a flow rate between four thousand and twenty thousand cubic feet per minute through the fluid flow path 28. As illustrated, in one configuration, the fan 24 may be located between the outlet 32 and the neck portion 34.
The heat shield 26 may be located between the heat source 22 and the fan 24. Specifically, the heat shield 26 may be located along a linear portion of the flow path 28 that extends from and between the heat source 22 and the fan 24. In this regard, the heat shield 26 may be located between one hundred fifty millimeters and four hundred seventy five millimeters from the fan 24. As illustrated, in one configuration the heat shield 26 is located between the heat source 22 and the neck portion 34, and generally centered within an inner peripheral surface 39 of the housing 20. In the example configuration, the heat shield 26 may be constructed of stainless steel. It will be appreciated, however, that the heat shield 26 may be constructed of other materials such as ceramic, aluminum, titanium, or steel within the scope of the present disclosure.
As illustrated in FIGS. 2, 3A and 4A, in one configuration, the heat shield 26 a may be defined by edges 40 a, 40 b, 40 c and 40 d of equal length. An angle α1 between edge 40 a and edge 40 b and an angle α2 between edge 40 c and edge 40 d may be between forty degrees and one hundred degrees. In one configuration, the angles α1 and α2 may be substantially equal to sixty-eight degrees. Likewise, an angle α3 between edge 40 a and edge 40 d and an angle α4 between edge 40 b and edge 40 c may be between seventy-one degrees and one hundred forty degrees. In one configuration, the angles α3 and α4 may be substantially equal to one hundred ten degrees.
The heat shield 26 a may include a thickness T1 extending along and in the direction of the flow path 28. The thickness T1 may be between two hundred seventy five millimeters and three hundred eighty millimeters. In one configuration, the thickness T1 may be substantially equal to two hundred thirty millimeters. Accordingly, it will be appreciated that the heat shield 26 a may be substantially defined by a first square pyramid 44 a and a second square pyramid 44 b, such that an apex 46 a of the first square pyramid 44 a generally faces the heat source 22 and an apex 46 b of the second square pyramid 46 b generally faces the fan 24.
While the heat shield 26 is generally illustrated and described herein as being defined by first and second square pyramids 44 a, 44 b it will be appreciated that the profile of the heat shield 26 may have other shapes within the scope of the present disclosure. For example, the heat shield 26 may be defined by other first and second pyramidal shapes. In one configuration, the heat shield 26 b may be defined by first and second tetrahedrons (FIGS. 3B and 4B). In other configurations, the heat shield 26 may be defined by first and second pentaganol pyramids (not shown) or first and second hexagonal pyramids (not shown).
It will also be appreciated that the heat shield 26 may be defined by other non-pyramidal shapes within the scope of the present disclosure. In this regard, the heat shield 26 may include various shapes such that a first non-planar surface of the heat shield 26 generally faces the heat source 22 and a second non-planar surface of the heat shield 26 generally faces the fan 24. As illustrated in FIG. 3C, in one configuration, the heat shield 26 c may be defined by a substantially cubic shape, such that a leading edge 48 a of the heat shield 26 c generally faces the heat source 22 and a trailing edge 48 b of the heat shield 26 c generally faces the fan 24. As illustrated in FIG. 3D, in yet another configuration the heat shield 26 d may be defined by a substantially conical shape having an arcuate, or otherwise non-planar surface 50 d, and an apex 52 d. The heat shield 26 d may be located within the housing 20 such that the non-planar surface 50 d generally faces the heat source 22 and the apex 52 d generally faces the fan 24. With reference to FIG. 3E, in yet another configuration, the heat shield 26 e may be a substantially cylindrical construct. The heat shield 26 e may be located within the housing 20 such that the non-planar peripheral surface 54 e of the heat shield 26 e generally faces the heat source 22 and the fan 24.
With reference to FIG. 3F, FIG. 4C and FIG. 5, in yet another configuration, the heat shield 26 f may include a first conical member 56 a and a second conical member 56 b. The first conical member 56 a may include a first base 58 a and a first apex 60 a. The second conical member 56 b may include a second base 58 b and a second apex 60 b. The first base 58 a may be concentrically aligned with, and mounted to, the second base 58 b, such that the first apex 60 a generally opposes the second apex 60 b. In one configuration, the first and second bases 58 a, 58 b may be substantially circular in shape, such that the first and second conical members 56 a, 56 b generally define circular right angle cones. Accordingly, it will be appreciated that a cross section of the first and second conical members 56 a, 56 b may generally define a rhombus-shaped construct (FIG. 5). In other configurations, the first and second bases 58 a, 58 b may define other shapes, such as an oval, or other multi-sided polygon. The first conical member 56 a may be similarly sized and shaped as the second conical member 56 b. In this regard, the first and second conical members 56 a, 56 b may define a cone angle β. The cone angle β may be between fifteen degrees and seventy degrees. In one configuration, the cone angle β may be substantially equal to fifty-one degrees.
The heat shield 26 may be operable to produce a Venturi flow pattern in the air moving through the flow path 28. Specifically, the heat shield 26 may produce a Venturi effect in the flow pattern around the heat shield 26. In this regard, the flow path 28 may include the cross-sectional area A1 upstream of the heat shield 26 and the cross-sectional area A3 downstream of the heat shield 26, as described above. The heat shield 26 may have a cross-sectional area A4 measured in a plane that is substantially perpendicular to the flow path 28, such that the heat shield 26 creates a partial restriction in the flow path 28. Accordingly, a cross-sectional area A5 of the flow path 28 around the heat shield 26 may be calculated as:
A5=A1−A4
The cross-sectional area A5 may be between twelve percent and seventy-five percent of the cross-sectional area A1. In one configuration, the cross-sectional area A5 may be substantially equal to twenty-one percent of the cross-sectional area A1.
As the air flows from a portion of the flow path 28 having a larger cross-sectional area A1 to a portion of the flow path 28 having the smaller cross-sectional area A5, a fluid pressure P2 at the area A1 is greater than a fluid pressure P5 at the area A5. In order to satisfy the principle of conservation of energy, the fluid may accelerate toward the area A5, such that a velocity of the air flowing through the area A5 is greater than a velocity of the air flowing through the area A1. As will be explained in more detail below, the acceleration and greater velocity at the area A5 may allow the heated air from the burner 36 to cool before it reaches the fan 24. Specifically, a temperature T3 of the air at the area A3 (downstream of the heat shield 26) may be lower than a temperature T1 of the air at the area A1 (upstream of the heat shield 26).
Operation of the heating unit 10 will now be described in more detail. In one mode of operation, the heating unit 10 may be placed in an exterior location, or otherwise outside of the heated space. In other modes of operation, the heating unit 10 may be placed in any suitable location such that the inlet 30 is in fluid communication with a space outside of, or exterior to, the heated space (or within the heated space, depending on the application), and the outlet 32 is in fluid communication with the heated space. Various temperature, humidity, and air quality sensors may be placed in the heated space, and in communication with (e.g., wired or wireless) the heating unit 10. In this regard, the control system 14 may be programmed such that the heating unit 10 operate when one of the sensors sends a signal to the heating unit 10 that the temperature, humidity, or other measure of air quality has deviated from a pre-programmed or user-specified value.
Operation of the heating unit 10 may include providing fuel, such as natural gas or propane, to the burner 36 in order to produce a flame. Power may be supplied to the fan 24, such that the fan produces a flow of air through the flow path 28. The fan 24 may draw the air through the inlet 30, over the burner 36, around the heat shield 26, through the neck portion 34, through the fan 24, and out the outlet 32. As the air is drawn around the heat shield 26, it may experience the Venturi effect, such that the temperature T3 is less than the temperature T2, as described above. In this way, the heat shield 26 is able to protect the fan 24 from the high temperatures of the heat produced by the burner 36, and from damage that might otherwise be caused thereby. In addition, the location of the heat shield 26 between the heat source 22 and the fan 24 can protect the fan 24 from the radiant heat produced by the flame on the burner 36. In this way, the heat shield 26 can act as a shield to hide or otherwise block the burner 36 from the fan 24 along all linear paths therebetween.
By ensuring that the temperature T3 downstream of the heat shield 26 is lower than the temperature T2 upstream of the heat shield, the heat shield also allows for the use of a housing 20 having a shorter overall length X1. Specifically, the housing 20 may require a shorter overall length X1 to obtain the same value of temperature reduction that would otherwise be obtained in a heating unit 10 that is operating without a heat shield 26. In this regard, the housing 20 may be sized such that a distance X2 from the burner 36 to the heat shield 26 is between three hundred thirty millimeters and five hundred forty-six millimeters, and a distance X3 from the heat shield 26 to the fan 24 is between three hundred four millimeters and five hundred eight millimeters. In one configuration the distance X2 (FIG. 1) may be substantially equal to four hundred seventy millimeters and the distance X3 may be substantially equal to four hundred thirty-one millimeters.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Claims

What is claimed is:

1. A portable heating apparatus comprising:

a housing including a fluid inlet and a fluid outlet, the fluid inlet in fluid communication with the fluid outlet;

a heat source disposed within the housing;

a fan for creating a flow of fluid from the inlet to the outlet, the fan disposed between the heat source and the outlet; and

a heat shield disposed between the heat source and the fan, the heat shield operable to restrict the flow of fluid between the heat source and the fan.

2. The portable heating apparatus of claim 1, further comprising a structure separating a first volume of fluid from a second volume of fluid, wherein the outlet is in fluid communication with the first volume of fluid and the inlet is in fluid communication with the second volume.

3. The portable heating apparatus of claim 1, wherein the heat shield includes a first square pyramid having a first apex and a second square pyramid having a second apex, and wherein the first apex generally faces the heat source and the second apex generally faces the fan.

4. The portable heating apparatus of claim 1, wherein a cross-sectional shape of the heat shield substantially defines a rhombus.

5. The portable heating apparatus of claim 1, wherein the housing includes a Venturi flow pattern between the inlet and the outlet.

6. The portable heating apparatus of claim 1, wherein the heat shield includes a first non-planar surface and a second non-planar surface, and wherein the first non-planar surface generally faces the heat source and the second non-planar surface generally faces the fan.

7. The portable heating apparatus of claim 1, wherein the heat source includes a flame.

8. The portable heating apparatus of claim 1, wherein a fluid temperature on an upstream side of the heat shield is greater than a fluid temperature on a downstream side of the heat shield.

9. The portable heating apparatus of claim 1, further comprising a control system, wherein the control system is in communication with at least one sensor disposed within the second volume.

10. A portable heating apparatus comprising:

a heat source disposed within the housing;

a heat shield disposed between the heat source and the fan, the heat shield including a first conical construct having a first apex and a second conical construct having a second apex,

wherein the first apex generally faces the heat source and the second apex generally faces the fan.

11. The portable heating apparatus of claim 10, further comprising a structure separating a first volume of fluid from a second volume of fluid, wherein the outlet is in fluid communication with the first volume of fluid and the inlet is in fluid communication with the second volume.

12. The portable heating apparatus of claim 10, wherein a cross-sectional shape of the heat shield substantially defines a rhombus.

13. The portable heating apparatus of claim 10, wherein the housing includes a Venturi flow pattern between the inlet and the outlet.

14. The portable heating apparatus of claim 10, wherein the heat shield includes a first non-planar surface and a second non-planar surface, and wherein the first non-planar surface generally faces the heat source and the second non-planar surface generally faces the fan.

15. The portable heating apparatus of claim 10, wherein the heat source includes a flame.

16. The portable heating apparatus of claim 10, wherein a fluid temperature on an upstream side of the heat shield is greater than a fluid temperature on a downstream side of the heat shield.

17. The portable heating apparatus of claim 10, further comprising a control system, wherein the control system is in communication with at least one sensor disposed within the second volume.