Virtual sensing system
A heating system includes at least one electric heater disposed within the fluid flow system. A control device includes a microprocessor and is configured to determine a temperature of the at least one electric heater based on a model and at least one input from the fluid flow system. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.
1. A heating system for a fluid flow system, the heating system comprising:
at least one electric heater disposed within the fluid flow system; and
a control device including a microprocessor and configured to determine a temperature of
the at least one electric heater based on a model and at least one fluid flow system input and at least one heater input, wherein:
the at least one fluid flow system input includes a mass flow rate of a fluid flow within a fluid flow pathway, a flow velocity of the fluid flow, a flow temperature upstream of the at least one electric heater, a flow temperature downstream of the at least one electric heater, and combinations thereof,
the at least one heater input includes at least one physical characteristic of the heating system, the at least one physical characteristic includes a resistance wire diameter, a heater insulation thickness, a heater sheath thickness, a conductivity, a specific heat and density of the material of the heater, an emissivity of the heater and the fluid flow pathway, or combinations thereof, and
the control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.
2. The heating system according to claim 1 , wherein the at least one electric heater is one of a band heater, a bare wire resistive heating element, a cable heater, a cartridge heater, a layered heater, a strip heater, and a tubular heater.
3. The heating system according to claim 1 , wherein the temperature of the at least one electric heater is a sheath temperature.
4. The heating system according to claim 1 , wherein the control device is configured to determine the temperature of the at least one electric heater based on the model and at least one further input including at least one of a set point, a mass flow rate, an inlet temperature, and radiation effects.
5. The heating system according to claim 4 , wherein the mass flow rate is determined based on at least one of a torque demand, a pedal position, a manifold absolute pressure (MAP), a boost timing, an engine timing, a fuel consumption, and an inlet air mass flow rate.
6. The heating system according to claim 1 , wherein the at least one physical characteristic further includes heat transfer coefficients.
7. An engine system comprising the heating system according to claim 1 .
8. The engine system according to claim 7 , wherein the control device is configured to receive engine inputs that include engine parameters, fluid flow parameters, electrical power output, heater parameters, or a combination thereof, and the control device is configured to generate an output that includes a power consumption, a fluid flow temperature, a heater temperature, a diagnostic, a fluid flow mass flow rate, or combination thereof.
9. The engine system according to claim 7 , wherein the heating system is configured to diagnose degrading engine system components.
10. The engine system according to claim 7 , wherein the heating system is in communication with an engine control unit and configured to trigger a diagnostic trouble code when a determined parameter is mismatched with a preset parameter.
11. The heating system according to claim 1 , wherein the at least one electric heater includes a resistive heating element.
12. The heating system according to claim 1 , wherein the temperature of the at least one electric heater is a sheath temperature, and wherein the control device is configured to determine the sheath temperature based on the following equation
T
s
=
T
o
u
t
+
(
k
W
A
s
)
K
D
{
C
2
·
C
·
Pr
0.36
(
P
r
Pr
s
)
0.25
[
D
μ
(
S
T
S
T
-
D
)
(
M
i
n
+
M
fuel
A
c
)
]
m
}
where:
A c is a heater cross-sectional area,
A s is a sheath area,
C is a first constant based on Reynolds number,
C 2 is an offset based on the number of heater elements in the at least one electric heater,
D is a heater element diameter,
K is a thermal conductivity of air,
kW is a total heater power,
M fuel is a mass flow rate of fuel,
M in is an inlet mass air flow rate,
m is a second constant based on Reynolds number,
Pr is a Prandtl number of air taken at gas temperature,
Pr s is a Prandtl number of air taken at sheath temperature;
S T is a transverse distance between heater elements,
T out is a heater outlet temperature, and
μ is a viscosity of air.
13. The heating system according to claim 1 , wherein the temperature of the at least one electric heater is a sheath temperature, and wherein the control device is configured to determine the sheath temperature based on the following equation
T
s
=
T
o
u
t
+
T
in
2
+
(
C
P
·
m
.
(
T
o
u
t
+
T
in
)
A
s
)
K
D
{
C
2
·
C
·
Pr
0.36
(
P
r
Pr
s
)
0.25
[
D
μ
(
S
T
S
T
-
D
)
(
M
i
n
+
M
fuel
A
c
)
]
m
}
where,
A c is a heater cross-sectional area,
A s is a sheath area,
C is a constant based on Reynolds number,
C 2 is an offset based on the number of heater elements in the at least one electric heater,
C p is a specific heat of air at constant pressure,
D is a heater element diameter,
K is a thermal conductivity of air,
M fuel is a mass flow rate of fuel,
M in is an inlet mass air flow (MAF) rate,
m is a constant based on Reynolds number,
{dot over (m)} is a mass flow rate,
Pr is a Prandtl number of air taken at gas temperature,
Pr s is a Prandtl number of air taken at sheath temperature,
S T is a transverse distance between heater elements,
T in is a heater inlet temperature,
T out is a heater outlet temperature, and
μ is a viscosity of air.
14. A heating system for a fluid flow system, the heating system comprising:
at least one electric heater disposed within a fluid flow pathway; and
a control device including a microprocessor and configured to receive at least one fluid flow system input and at least one heater input, the at least one fluid flow system input including a mass flow rate of the fluid flow system, a fluid inlet temperature, an outlet temperature, or combination thereof, the at least one heater input includes at least one physical characteristic of the heating system, wherein the at least one physical characteristic includes a resistance wire diameter, a heater insulation thickness, a heater sheath thickness, conductivity, a specific heat and density of the material of the heater, an emissivity of the heater and the fluid flow pathway, or combinations thereof;
wherein the control device is configured to determine a temperature of the at least one electric heater based on a model, the at least one fluid flow system input, and the at least one heater input, wherein the control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.
15. The heating system according to claim 14 , wherein the temperature of the at least one electric heater is a sheath temperature, and wherein the control device is configured to determine the sheath temperature based on the following equation:
T
s
=
T
o
u
t
+
(
k
W
A
s
)
K
D
{
C
2
·
C
·
Pr
0.36
(
P
r
Pr
s
)
0.25
[
D
μ
(
S
T
S
T
-
D
)
(
M
i
n
+
M
fuel
A
c
)
]
m
}
where:
A c is a heater cross-sectional area,
A s is sheath area,
C is a first constant based on Reynolds number,
C 2 is an offset based on the number of heater elements in the at least one electric heater,
D is a heater element diameter,
K is a thermal conductivity of air,
kW is a total heater power,
M fuel is a mass flow rate of fuel,
M in is an inlet mass air flow rate,
m is a second constant based on Reynolds number,
Pr is a Prandtl number of air taken at gas temperature,
Pr s is a Prandtl number of air taken at sheath temperature;
S T is a transverse distance between heater elements,
T out is a heater outlet temperature, and
μ is a viscosity of air.
16. The heating system according to claim 14 , wherein the temperature of the at least one electric heater is a sheath temperature, and wherein the control device is configured to determine the sheath temperature based on the following equation
T
s
=
T
o
u
t
+
T
in
2
+
(
C
P
·
m
.
(
T
o
u
t
+
T
in
)
A
s
)
K
D
{
C
2
·
C
·
Pr
0.36
(
P
r
Pr
s
)
0.25
[
D
μ
(
S
T
S
T
-
D
)
(
M
i
n
+
M
fuel
A
c
)
]
m
}
where,
A c is a heater cross-sectional area,
A s is a sheath area,
C is a constant based on Reynolds number,
C 2 is an offset based on the number of heater elements in the at least one electric heater,
C p is a specific heat of air at constant pressure,
D is a heater element diameter,
K is a thermal conductivity of air,
M fuel is a mass flow rate of fuel,
M in is a inlet mass air flow (MAF) rate,
m is a constant based on Reynolds number,
{dot over (m)} is a mass flow rate,
Pr is a Prandtl number of air taken at gas temperature,
Pr s is a Prandtl number of air taken at sheath temperature,
S T is a transverse distance between heater elements,
T in is a heater inlet temperature,
T out is a heater outlet temperature, and
μ is a viscosity of air.
17. The heating system according to claim 14 , wherein the temperature of the at least one electric heater is an outlet temperature, and wherein the control device is configured to determine the outlet temperature based on the following equation
T
o
u
t
,
1
=
2
·
m
.
·
C
P
·
T
in
,
1
+
h
·
A
s
(
2
T
s
-
T
in
,
1
)
2
·
m
.
·
C
P
+
h
·
A
s
where:
A s is a sheath surface area;
C p is a specific heat of air at constant pressure;
h is a convective heat transfer coefficient;
{dot over (m)} is a mass flow rate;
T out,1 is an outlet temperature after a first component;
T in,1 is an inlet temperature of the first component; and
T S is a sheath temperature.
18. The heating system according to claim 14 , wherein the at least one electric heater is one of a band heater, a bare wire resistive heating element, a cable heater, a cartridge heater, a layered heater, a strip heater, and a tubular heater.
19. The heating system according to claim 14 , wherein the control device is configured to determine the temperature of the at least one electric heater based on the model and at least one further input including at least one of a set point and radiation effects.
20. The control system according to claim 14 , wherein the mass flow rate of the fluid flow system is determined based on at least one of a torque demand, a pedal position, a manifold absolute pressure (MAP), a boost timing, an engine timing, a fuel consumption, and an inlet air mass flow rate.
21. The heating system according to claim 14 , wherein the at least one physical characteristic further includes heat transfer coefficients.
22. An engine system comprising the heating system according to claim 14 .
23. The engine system according to claim 22 , wherein the control device is configured to receive engine inputs that include engine parameters, fluid flow parameters, electrical power output, heater parameters, or a combination thereof, and the control device is configured to generate an output that includes a power consumption, a fluid flow temperature, a heater temperature, a diagnostic, or combination thereof.
24. The engine system according to claim 22 , wherein the heating system is configured to diagnose degrading engine system components.
25. The engine system according to claim 22 , wherein the heating system is in communication with an engine control unit and configured to trigger a diagnostic trouble code when a determined parameter is mismatched with a preset parameter.
26. The heating system according to claim 14 , wherein the at least one electric heater includes a resistive heating element.
27. The heating system according to claim 14 , wherein the at least one heater input includes a power input to the at least one electric heater.