Flow sensor devices and systems

A flow rate assembly comprising:

• a sensor body configured to be positioned at least partially outside of a pipe when the flow rate assembly is installed on the pipe the sensor body having:
• a first end;
• a second end opposite the first end;
• a fluid passage positioned entirely within the sensor body and extending from an inlet in the second end, toward the first end, and back through an outlet in the second end;
• a fluid flow interface portion connected to the second end of the sensor body and configured to be positioned at least partially within an interior of the pipe when the flow rate assembly is installed on the pipe, the fluid flow interface portion comprising an inlet passage in direct fluid communication with the inlet of the fluid passage of the sensor body, an outlet passage separate from the inlet passage and in direct fluid communication with the outlet of the fluid passage of the sensor body, a plurality of inlet apertures extending through a wall of the fluid flow interface portion into the inlet passage, and an outlet aperture extending through a wall of the fluid flow interface portion on a side of the fluid flow interface portion opposite the inlet apertures into the outlet passage;
• and
• a float positioned at least partially within the fluid passage of the sensor body, wherein a position of the float between the first and second ends of the sensor body indicates a flow rate of fluid into the plurality of inlet apertures of the fluid flow interface portion.

A flow rate assembly comprising:

• a sensor body positioned at least partly outside a pipe when the flow rate assembly is installed on the pipe;
• and
• a fluid flow interface portion connected to the sensor body and positioned at least partially when the pipe when the flow rate assembly is installed on the pipe, the fluid flow interface portion comprising:
• a first end connected to the sensor body;
• a second end;
• a length measured from the first end of the fluid flow interface portion and the second end of the fluid flow interface portion;
• a front face extending at least partially between the first and second ends of the fluid flow interface portion;
• a rear face extending at least partially between the first and second ends of the fluid flow interface portion opposite the front face;
• an inlet passage within the fluid flow interface portion and extending along at least a portion of the length of the fluid flow interface portion;
• an outlet passage within the fluid flow interface portion and separated from the inlet passage, the outlet passage extending along at least a portion of the length of the fluid flow interface portion;
• a first plurality of inlet apertures extending through the front face into the inlet passage;
• a second plurality of inlet apertures extending through the front face into the inlet passage, the second plurality of inlet apertures spaced from the first plurality of inlet apertures along the length of the fluid flow interface portion;
• and
• an outlet aperture extending through the rear face into the outlet passage;
• wherein an average position of the first plurality of inlet apertures along the length of the fluid flow interface portion is between 2/9 and ⅝ of a radius of the pipe from an axial centerline of the pipe and an average position of the second plurality of inlet apertures along the length of the fluid flow interface portion on an opposite side of the axial centerline of the pipe is between 2/9 and ⅝ of the radius of the pipe from an axial centerline of the pipe when the flow rate assembly is installed on the pipe, and wherein each of the first plurality of inlet apertures is positioned on one side of the axial centerline of the pipe and each of the second plurality of inlet apertures is positioned on another side of the axial centerline of the pipe.

A fluid flow assembly comprising:

• a sensor body positioned at least partly outside a pipe when the flow rate assembly is installed on the pipe;
• and
• a fluid flow interface portion connected to the sensor body and positioned at least partially when the pipe when the flow rate assembly is installed on the pipe, the fluid flow interface portion comprising:
• a first end connected to the sensor body;
• a second end;
• a length measured from the first end of the fluid flow interface portion and the second end of the fluid flow interface portion;
• a front face extending at least partially between the first and second ends of the fluid flow interface portion;
• a rear face having a length extending at least partially between the first and second ends of the fluid flow interface portion opposite the front face;
• a recess formed along at least a portion of the length of the rear face;
• an inlet passage having a length within the fluid flow interface portion and extending along at least a portion of the length of the fluid flow interface portion;
• an outlet passage within the fluid flow interface portion and separated from the inlet passage, the outlet passage extending along at least a portion of the length of the fluid flow interface portion;
• a first plurality of inlet apertures extending through the front face into the inlet passage;
• a second plurality of inlet apertures extending through the front face into the inlet passage, the second plurality of inlet apertures spaced from the first plurality of inlet apertures along the length of the fluid flow interface portion;
• and
• an outlet aperture extending through the rear face into the outlet passage;
• and
• a plug configured to mate with the recess of the fluid flow interface portion, the plug forming at least a portion of a wall of the inlet passage and extending along at least ⅓ of the length of the inlet passage.