Abstract: A portable electrohydraulic servo valve analyzer, which has microprocessor-based electronic controller and is operable in a fully automatic mode and a manual mode, is disclosed. The system also includes: a hydraulic manifold block and an adapter block for receiving different servo valve; a servo amplifier and electrical hook-up to the servo valve; pressure gages and hydraulic shut-off valves; a keypad for entering operating input commands and values; two digital displays indicating the current supplied to the valve and the resulting hydraulic flow rate through the valve, and a special turbine flowmeter capable of highly accurate operation of at least three orders of magnitude of flow rates. Most of the system is housed in a single small portable aluminum suitcase. Hydraulic flow is measured by digitally timing the periods between detection of the successive rotating vanes of the turbine, and compensating for nonlinearities in turbine rotation rate at low flows.

Abstract: An electronic flowmeter system including a turbine flowmeter and a digital controller for making highly accurate flow measurements over a wide range of fluid flows and pressures is disclosed. The flowmeter preferably includes a body having a cylindrical bore in which is mounted a turbine having multiple vanes which rotate transversely to the direction of fluid flow. The clearance between the bore and vanes is selected for minimum resistance to fluid flow at extremely low flow rates. Rotation of the turbine vanes is detected by use of a proximity sensor or an optical sensor employing an artificial light and a photodetector. Flow measurements are made by digitally measuring the time periods between successive input pulses generated by detection of the rotating vanes of the turbine. For high temperature or intrinsically safe applications, the optical sensor is used with a fiber optic cable so that the light source and photodetector can be located remotely from the flowmeter.

Abstract: An electronic flowmeter system including a turbine flowmeter and a digital controller for making highly accurate flow measurements over a wide range of fluid flows and pressures. The flowmeter preferably includes a housing or body having a cylindrical bore in which is mounted a turbine having multiple vanes, and which preferably rotates transversely to the direction of fluid flow. The clearance between the bore and outer edge of the vanes is selected for minimum resistance to extremely low flow rates. Rotation of the turbine vanes is detected by use of a proximity sensor or an optical sensor employing an artificial light source and a photodetector. Fiber optics may be used to locate the light source and photodetector at a location remote from the flowmeter for high temperature or intrinsically safe applications. Flow measurements are made by digitally measuring the time periods between successive input generated by detection of the rotating vanes of the turbine.