Device and method for detecting a volume while receiving and/or discharging a fluid having a gas portion
The invention relates to a device for detecting an amount while receiving and/or discharging a fluid having a gas portion comprising a measurement line for conducting the fluid, a flow measuring unit for the fluid, which is in fluid connection with the measurement line, a degree of filling measuring unit for the fluid, which is in fluid connection with the measurement line and which comprises an electrode arrangement for determining electrical properties of the fluid present in the measurement line, and an evaluation unit for determining the fluid amount conveyed which is in a signal connection with the degree of filling measuring unit and the flow measuring unit. According to the invention it is provided that the electrode arrangement of the degree of filling measuring unit has a plurality of electrode plates which form a plate stack in the region of the measurement line.
1. Device for detecting an amount of fluid flowing between two points and having a gas portion, comprising:
a measurement line for conducting the fluid between the two points, the measurement line including:
a flow measuring unit for measuring the rate of flow of the fluid in the measurement line,
a degree of filling measuring unit for measuring the degree of filling in the measurement line, wherein the degree of filling measuring unit comprises an electrode arrangement for determining electrical properties of the fluid present in the measurement line, wherein the electrode arrangement has a plurality of electrode plates which form a plate stack and determine electrical properties that vary according to the gas portion of the fluid flowing through the plate stack,
an evaluation unit in a signal connection with the degree of filling measuring unit and the flow measuring unit for determining the fluid amount conveyed through the measurement line based on the measurements made by the flow measuring unit and the degree of filling measuring unit,
means for stopping the fluid flow in the measurement line at least at times, and
means for determining a remaining fluid amount present in the measurement line downstream of the flow measuring unit and the degree of filling measuring unit based on the results of the measurements made by the flow measuring unit and the degree of filling measuring unit.
2. Method for detecting an amount of a fluid, having a gas portion at least at times, using the device according to claim 1 , wherein the fluid is flowing in the measurement line, the method comprising the steps of:
carrying out a degree of filling measurement in the measurement line by means of the degree of filling measuring unit,
carrying out a flow measurement in the measurement line by means of the flow measuring unit,
calculating the amount of fluid conveyed from the results of the flow measurement step and the results of the degree of filling measurement step, using the evaluation unit,
intermittently stopping the fluid flow in the measurement line, and
determining a remaining fluid amount present in the measurement line downstream of the flow measuring unit and the degree of filling measuring unit from the results of the flow measurement step and the results of the degree of filling measurement step, using the means for determining a remaining fluid amount.
3. Method according to claim 2 ,
wherein
at least one of the temperature, the pressure and the speed of the fluid in the measurement line is determined and the results are included in the step of calculating the amount of fluid conveyed.
4. Method according to claim 2 , further comprising the steps of:
deducting the amount of remaining fluid, as determined in the step of determining a remaining fluid amount, from the amount of fluid conveyed, as calculated in the calculating the amount of fluid conveyed step and
adding the amount of remaining fluid, as determined in the step of determining a remaining fluid amount, to the amount of fluid conveyed, as calculated in the calculating the amount of fluid conveyed step, determined after resumption of the fluid flow.
5. Method according to claim 2 , further comprising the step of:
recalibrating the degree of filling measuring unit with an ongoing degree of filling measurement.
6. Device according to claim 2 , wherein the fluid is one of milk and fuel.
7. Device according to claim 1 ,
wherein
at least one of the electrode plates of the plate stack is arranged inside the measurement line,
at least two electrode plates of the plate stack extend parallel to each other,
the electrode plates of the plate stack are arranged equidistantly,
the electrode plates of the plate stack have at least approximately the same surface size and
the electrode plates of the plate stack are flat rectangular plates.
8. Device according to claim 1 ,
wherein
the electrode plates extend in the longitudinal direction of the measurement line, and
through channels for the fluid which extend in the longitudinal direction of the measurement line are formed between the electrode plates.
9. Device according to claim 1 ,
wherein
the measurement line has a rectangular inner cross-section, and
the outer cross-section of the plate stack corresponds at least approximately to the rectangular inner cross-section of the measurement line.
10. Device according to claim 1 ,
wherein
the electrode plates of the plate stack are electrically connected to form two groups of plates which form an interdigitated structure.
11. Device according to claim 1 ,
wherein
the degree of filling measuring unit is a capacitive measuring unit and
the electrode plates are electrically insulated in relation to the inside of the measurement line.
12. Device according to claim 1 ,
wherein
the flow measuring unit is a turbine flow meter.
13. Device according to claim 1 ,
further comprising a tank, wherein the tank is in fluid connection with the measurement line.
14. Device according to claim 1 ,
wherein
the measurement line is formed in a straight line, in the region of the flow measuring unit and the degree of filling measuring unit and
the measurement line extends at an angle to the horizontal, in the region of the flow measuring unit and the degree of filling measuring unit, and wherein the height of the measurement line decreases with increasing distance from the tank.
15. Device according to claim 1 ,
wherein
the flow measuring unit and the degree of filling measuring unit are arranged directly one behind the other in the course of the measurement line.
16. Device according to claim 1 ,
further comprising a control unit for controlling a flow through the measurement line in dependence upon the measured degree of filling.
17. Device according to claim 1 ,
further comprising a reducing unit provided in the measurement line for reducing gas pockets in the fluid before the fluid reaches the degree of filling measuring unit and the flow measuring unit.
18. Device according to claim 1 , wherein the fluid is one of milk and fuel.
19. Device according to claim 17 , wherein the reducing unit is one of a sieve and a filter.