US 4,384,792 A · Process and apparatus for the combustionless measurement and/or control of the amount of heat fed to gas consumption devices

Abstract

A process and apparatus for the combustion-less measurement and/or regulation of the feeding of quantities of heat to gas combustion devices, particularly natural-gas combustion devices. A fuel gas or a partial stream of the fuel gas is fed through a fuel gas line containing at least one flow resistor which produces a laminar flow and a pressure drop. The gas volume flow and/or the pressure drop over at least one flow resistor is measured by a volume flow metering device and a difference pressure regulator, respectively, the pressure drops and/or volume flows which are not measured being maintained constant. A device compensates for the influence of temperature on the system is compensated. The measured value(s) in accordance with the formula described in the specification f (H)= a+b.multidot.n.sup.c .multidot..rho..sup.d is a measure of the heat content of the flowing gas and results in a signal which serves for measurement and/or regulation.

Claims34

Dependent claims

A process for the combustionless measurement and/or regulation of the feeding of quantities of heat to gas combustion devices, comprising the steps of

conducting at least a partial stream of a fuel gas through at least one flow resistance which produces a laminar flow and a pressure drop,
measuring at least one of the gas volume flow and the pressure drop over at least one flow resistance,
maintaining constant at least one of the pressure drops and the gas volume flow which are not measured,
compensating for the influence of temperature on the system, and
deriving a signal for at least one of measurement and regulation utilizing the measured value(s) as a measure of the heat content of the flowing gas according to the formula:
f(H)=a+b.multidot.n.sup.c .multidot..rho..sup.d
where:
f (H) being a function of heat of reaction of the gas;
a, b, c, and d are constants;
n is the dynamic gas viscosity which is obtained from the equation n.about.(.DELTA.p.sub.1 /V.sub.1)
where .DELTA.p.sub.1 is the pressure difference with laminar flow and V.sub.1 is the volumetric flow;
and
.rho. is the operating gas density which is obtained from the equation .rho..about.(.DELTA.p.sub.t /V.sub.t.sup.2) where .DELTA.p.sub.t and V.sub.t are the pressure difference and volumetric flow respectively with turbulent flow.

10 more elements

A method for the combustionless measurement and/or regulation of the quantity of heat fed to gas consumption devices, comprising the steps of

conducting at least a partial stream of fuel gas through at least two flow resistances, at least one of which produces a laminar flow and another a turbulent flow and corresponding pressure drops,
maintaining a constant pressure drop over all of said flow resistances together,
measuring the pressure drop over at least one flow resistance,
compensating for the influence of temperature,
deriving a signal for at least one of measurement and regulation utilizing the measured value(s) as a measure of the heat content of the flowing gas according to the formula:
f(H)=a+b.multidot.n.sup.c .multidot..rho..sup.d
where:
f (H) being a function of heat of reaction of the gas;
a, b, c, and d are constants;
n is the dynamic gas viscosity which is obtained from the equation n.about.(.DELTA.p.sub.1 /V.sub.1)
where .DELTA.p.sub.1 is the pressure difference with laminar flow and V.sub.1 is the volumetric flow;
and
.rho. is the operating gas density which is obtained from the equation .rho..about.(.DELTA.p.sub.t /V.sub.t.sup.2) where .DELTA.p.sub.t and V.sub.t are the pressure difference and volumetric flow respectively with turbulent flow.

10 more elements

An arrangement for the combustionless measurement and/or regulation of the feeding of quantities of heat to gas combustion devices, comprising

means for conducting at least a partial stream of a fuel gas through at least one flow resistance which produces a laminar flow and a pressure drop,
means for measuring at least one of the gas volume flow and the pressure drop over at least one flow resistance,
means for maintaining constant at least one of the pressure drops and the gas volume flow which are not measured,
means for compensating for the influence of temperature on the system, and
means for deriving a signal for at least one of measurement and regulation utilizing the measured value(s) as a measure of the heat content of the flowing gas according to the formula:
f(H)=a+b.multidot.n.sup.c .multidot..rho..sup.d where:
f(H) being a function of heat of reaction of the gas;
a, b, c, and d are constants;
n is the dynamic gas viscosity which is obtained from the equation n.about.(.DELTA.p.sub.1 /V.sub.1), where .DELTA.p.sub.1 is the pressure difference with laminar flow and V.sub.1 is the volumetric flow;
and .rho. is the operating gas density which is obtained from the equation .rho..about.(.DELTA.p.sub.t /V.sub.t.sup.2), where .DELTA.p.sub.t and V.sub.t are the pressure difference and volumetric flow respectively with turbulent flow, and wherein
said conducting means is a fuel gas line,
said means for maintaining constant includes a volume flow-metering device, and
said at least one flow resistance includes at least one laminar resistor arranged in a flow path in the fuel gas line,
said measuring means comprises difference pressure measuring means operatively connected with said laminar resistor for the measuring of the pressure drop,
said means for compensating for the influence of temperature on the system includes a thermostat,
a first of said at least one laminar resistor in the flow path is partially surounded by said thermostat.

13 more elements

An arrangement for the combustionless measurement and/or regulation of the feeding of quantities of heat to gas combustion devices, comprising

means for conducting at least a partial stream of a fuel gas through at least one flow resistance which produces a laminar flow and a pressure drop,
means for measuring at least one of the gas volume flow and the pressure drop over at least one flow resistance,
means for maintaining constant at least one of the pressure drops and the gas volume flow which are not measured,
means for compensating for the influence of temperature on the system, and
means for deriving a signal for at least one of measurement and regulation utilizing the measured value(s) as a measure of the heat content of the flowing gas according to the formula:
f(H)=a+b.multidot.n.sup.c .multidot..rho..sup.d where:
f(H) being a function of heat of reaction of the gas;
a, b, c, and d are constants;
n is the dynamic gas viscosity which is obtained from the equation n.about.(.DELTA.p.sub.1 /V.sub.1), where .DELTA.p.sub.1 is the pressure difference with laminar flow and V.sub.1 is the volumetric flow;
and .rho. is the operating gas density which is obtained from the equation .rho..about.(.DELTA.p.sub.t /V.sub.t.sup.2), where .DELTA.p.sub.t and V.sub.t are the pressure difference and volumetric flow respectively with turbulent flow, and wherein
said conducting means is a fuel gas line,
said measuring means comprises a volume-flow measuring device,
said at least one flow resistance includes at least one laminar resistor and at least one difference pressure regulator means arranged in a flow path in said fuel gas line, said regulator means constitutes said means for maintaining constant and is for maintaining constant the pressure drop on said laminar resistor,
said means for compensating for the influence of temperature includes a thermostat,
a first of said at least one laminar resistor in the flow path is partially surrounded by said thermostat.

12 more elements