Systems and techniques are described for a fluid diode. In some examples, a fluid diode can include a first fluid path for a first flow of fluid to traverse the fluid diode via a first flow direction and a second fluid path for a second flow of fluid to traverse the fluid diode via a second flow direction. The first flow direction can be associated with a first pressure drop and the second flow direction can be associated with a second pressure drop that is different than the first pressure drop. Moreover, the first fluid path and the second fluid path can be configured to remain open to the first flow and the second flow in the first flow direction and the second flow direction.

A viscometer includes a viscosity sensor with a liquid flow channel and at least two pressure sensors positioned along the liquid flow channel and configured to measure a pressure drop of a liquid flowing through the liquid flow channel, and a dispensing mechanism configured to cause dispensing of a liquid from the syringe to the viscosity sensor at a known flow rate. The dispensing mechanism and the viscosity sensor are configured to couple with a syringe configured to contain a liquid. The viscometer further includes an electronic controller configured to control operations of the dispensing mechanism and receive and process data from the viscosity sensor. The viscometer includes a sample loading interface, included in the syringe, through which the viscometer is configured to receive the liquid. The sample loading interface includes a selection valve coupled with, and located between, the viscosity sensor and the syringe.

A viscometer includes a viscosity sensor with a liquid flow channel and at least two pressure sensors positioned along the liquid flow channel and configured to measure a pressure drop of a liquid flowing through the liquid flow channel, and a dispensing mechanism configured to cause dispensing of a liquid from the syringe to the viscosity sensor at a known flow rate. The dispensing mechanism and the viscosity sensor are configured to couple with a syringe configured to contain a liquid. The viscometer further includes an electronic controller configured to control operations of the dispensing mechanism and receive and process data from the viscosity sensor. The viscometer includes a sample loading interface, included in the syringe, through which the viscometer is configured to receive the liquid. The sample loading interface includes a selection valve coupled with, and located between, the viscosity sensor and the syringe.

The present application provides a high-voltage cable insulation material continuous extrusion processing characteristic evaluation and optimization method and apparatus. The method comprises: continuously extruding a material under test as a melt, measuring and recording an inlet pressure P. a mass growth rate w, and the diameter D of a melt sample strip, and obtaining apparent shear viscosity .sub.a(t) (step A1); obtaining an outlet expansion rate (step A2); recording and displaying curves .sub.a(t) and (t), and treating the time corresponding to an increase of a set percentage on the curves as a cross-linking starting time TX (step A3); selecting a reference sample for testing, and determining a cross-linking reaction starting time T.sub.S according to .sub.a(t) and (t) curves of the reference sample (step A4); and defining an index according to T.sub.X and T.sub.S.

The present application provides a high-voltage cable insulation material continuous extrusion processing characteristic evaluation and optimization method and apparatus. The method comprises: continuously extruding a material under test as a melt, measuring and recording an inlet pressure P. a mass growth rate w, and the diameter D of a melt sample strip, and obtaining apparent shear viscosity .sub.a(t) (step A1); obtaining an outlet expansion rate (step A2); recording and displaying curves .sub.a(t) and (t), and treating the time corresponding to an increase of a set percentage on the curves as a cross-linking starting time TX (step A3); selecting a reference sample for testing, and determining a cross-linking reaction starting time T.sub.S according to .sub.a(t) and (t) curves of the reference sample (step A4); and defining an index according to T.sub.X and T.sub.S.

A fluid flows through a flowmeter system including a first conduit, a U-bend, and a second conduit. Various differential pressures of the fluid flowing through the flowmeter system are measured. The differential pressures of the fluid are measured by various pressure sensors (for example, differential pressure sensors) installed on the flowmeter system. Rheology of the fluid is characterized by performing calculations using the measured differential pressures of the fluid and relative positions of the pressure sensors throughout the flowmeter system.

A fluid flows through a flowmeter system including a first conduit, a U-bend, and a second conduit. Various differential pressures of the fluid flowing through the flowmeter system are measured. The differential pressures of the fluid are measured by various pressure sensors (for example, differential pressure sensors) installed on the flowmeter system. Rheology of the fluid is characterized by performing calculations using the measured differential pressures of the fluid and relative positions of the pressure sensors throughout the flowmeter system.

The present application provides a high-voltage cable insulation material continuous extrusion processing characteristic evaluation and optimization method and apparatus. The method comprises: continuously extruding a material under test as a melt, measuring and recording an inlet pressure P, a mass growth rate w, and the diameter D of a melt sample strip, and obtaining apparent shear viscosity .sub.a(t) (step A1); obtaining an outlet expansion rate (step A2); recording and displaying curves .sub.a(t) and (t), and treating the time corresponding to an increase of a set percentage on the curves as a cross-linking starting time TX (step A3); selecting a reference sample for testing, and determining a cross-linking reaction starting time TS according to .sub.a(t) and (t) curves of the reference sample (step A4); and defining an index according to Tx and Ts.

The present application provides a high-voltage cable insulation material continuous extrusion processing characteristic evaluation and optimization method and apparatus. The method comprises: continuously extruding a material under test as a melt, measuring and recording an inlet pressure P, a mass growth rate w, and the diameter D of a melt sample strip, and obtaining apparent shear viscosity .sub.a(t) (step A1); obtaining an outlet expansion rate (step A2); recording and displaying curves .sub.a(t) and (t), and treating the time corresponding to an increase of a set percentage on the curves as a cross-linking starting time TX (step A3); selecting a reference sample for testing, and determining a cross-linking reaction starting time TS according to .sub.a(t) and (t) curves of the reference sample (step A4); and defining an index according to Tx and Ts.

The invention relates to a method and device for measuring viscosity. A sample from a process tube (4) is drawn into a measuring unit (2) via a measurement capillary (1) or a gap or hole in the tube wall (5). The measuring unit (2) is located outside the wall (5). A sample is taken automatically by underpressure generated by a piston (3) moving within a cylinder (6). Viscosity is measured during the piston's opposite motion, which returns the sample to the process through the same measurement capillary, gap, or hole. The device includes a sampling/measurement capillary tube (1) and a measuring unit (2) comprising a cylinder (6) and a piston (3). The cylinder (6) is positioned at a gap or hole in the wall (5) to take a sample, measure viscosity, and return the sample, with the measurement capillary, gap, or hole serving as the sampling path.