Loading a fluidic element
The present invention relates to a method of loading a fluid into a fluidic element, wherein the method is performed in a fluidic system comprising the fluidic element, wherein the method comprises determining a volume that has flown into the fluidic element since a start time t start , and at a switching time t switch , switching the fluidic system to an operating state to stop flow into the fluidic element. The present invention also relates to a fluidic system configured for performing the method, and to a corresponding computer program product.
1 . A method of loading a fluid into a fluidic element of a fluidic system comprising the fluidic element and a loading pump, wherein the method comprises determining a volume that has flown into the fluidic element since a start time t start ;
at a switching time t switch , switching the fluidic system to an operating state to stop fluid flow into the fluidic element; and
operating the loading pump in a loading state from the start time t start to the switching time t switch , with the pressure between the loading pump and the fluidic element exceeding atmospheric pressure, and with the loading pump causing fluid to flow into the fluidic element in the loading state.
2 . The method according to claim 1 ,
wherein the switching the fluidic system to an operating state to stop fluid flow into the fluidic element comprises switching the loading pump to a stop state, wherein the pressure between the loading pump and the fluidic element equals atmospheric pressure in the stop state.
3 . The method according to claim 1 , further comprising determining the switch time t switch .
4 . The method according to claim 1 , wherein the determining the switch time t switch is based on the determined volume flown into the fluidic element since the start time t start .
5 . The method according to claim 1 , further comprising sensing a pressure in the loading pump or fluidly connected thereto, and wherein the determining the volume flown into the fluidic element since the start time t start is based on the sensed pressure.
6 . The method according to claim 3 , wherein the determining the switch time t switch is based on an expected fluid flow (V red ) into the fluidic element after the switch time t switch .
7 . The method according to claim 1 , wherein the loading pump is a non-continuous pump.
8 . The method according to claim 2 , further comprising switching a flow out of the fluidic element to zero, varying a pressure of the loading pump and measuring a volume of fluid compressed.
9 . The method according to claim 1 , further comprising,
at the start time t start , increasing the pressure in the loading pump to compress the fluid such that no fluid flows out of the fluidic element, and measuring a compression volume V lag , and comparing the measured compression volume V lag to an expected compression volume at a corresponding pressure.
10 . The method according to claim 1 , wherein the maximum pressure between the loading pump and the fluidic element in the loading state exceeds the atmospheric pressure by a maximum differential pressure,
wherein 0.2 s to 15 s after the switching time t switch , the pressure between the loading pump and the fluidic element minus the atmospheric pressure is less than 10% of the maximum differential pressure.
11 . The method according to claim 5 , wherein the determining the switch time t switch is based on a compressibility of the fluid at the sensed pressure.
12 . The method according to claim 6 , wherein the expected fluid flow (V red ) is obtained by integrating the flow running through the fluidic element during depressurization.
13 . The method according to claim 6 , wherein the expected fluid flow (V red ) is based on a fluidic resistance of the fluidic element.
14 . The method according to claim 13 , further comprising experimentally determining the fluidic resistance for different pressure values.
15 . A non-transitory computer-readable storage medium comprising instructions which, when executed on a control unit of a fluidic system, cause the fluidic system to
determine a volume flown into the fluidic element since a start time tstart;
at a switching time t switch , switch the fluidic system to an operating state to stop fluid flow into the fluidic element; and
operate the loading pump in a loading state from the start time tstart to the switching time t switch , with the pressure between the loading pump and the fluidic element exceeding atmospheric pressure, and with the loading pump causing fluid to flow into the fluidic element in the loading state.