Abstract: A process for delivering a predetermined ratio of a compressible fluid and a non-compressible fluid which comprises the measurement of only the flowrate of the compressible fluid, the activation of an air-driven positive displacement pump at appropriate times, the pumping of a non-compressible fluid with the air-driven pump, mixing the supercritical fluid and non-compressible fluid and depositing the mixture onto a substrate.

Abstract: In accordance with an illustrative embodiment of the present invention, an expansible chamber device includes a piston movable within a cylinder, a head on the cylinder having intake and exhaust ports, a normally-open intake valve for closing the intake port automatically when the flow rate or velocity of a working medium entering the cylinder reaches a predetermined value, variable restraining means for inhibiting closing of the intake valve in response to flow, an exhaust valve for preventing escape of working medium from the cylinder until cylinder pressure is reduced to a set level, spring means for opening the exhaust valve at that level, and means operable near the top-dead-center position of the piston for automatically opening the intake valve and for closing the exhaust valve to enable the cycle to repeat. A unique system for controlling the variable restraining means, as well as methods for regulating the flow or working medium through said valves, also is disclosed.

Abstract: A pipe flow detector for activating a solenoid to automatically close a pipe shutoff valve in the event of a leak. The detector comprises a piezoelectric film transducer attached to the pipe, the transducer producing a fluctuating electrical signal in response to pipe vibration. An amplifier amplifies the signal, which is then passed to a tunable low-pass filter. The output from the filter is passed to an averaging circuit to produce an electrical signal representative of the total voltage changes of the fluctuating electrical signals. An LED is connected to the output of the averaging circuit to provide a means to tune the filter.

Abstract: Method and apparatus for controlling fluid leakage from sections of a pressurized fluid system adapted to provide fluid at line pressure to equipment associated therewith includes means for sensing first and second conditions indicative of non-use and of a usage demand respectively of the equipment and for generating a signal indicative of one of the conditions and control unit means for selectively isolating and effecting communication between line pressure of the fluid system and the system section in response to the condition-indicating signal. According to a first embodiment, the first non-use and second usage demand conditions are constituted by respective lower and higher rates of fluid flow through the section of the fluid system in which leakage is to be controlled. According to a second embodiment of the invention, the first non-use and second usage demand conditions are constituted by support and non-support of the equipment respectively or non-movement and movement of the equipment respectively.

Abstract: A process for performing a series of hydrodynamic functions or operation on a flow of fluids comprised of at least two phases includes the following steps: separating the fluid phases that comprise the initial flow; reducing the turbulence of the flows of each of the fluid phases which have been separated from each other; and recombining the fluid phases to form a new polyphasic flow with a predetermined structure.

Abstract: Method and system for controlling fluid transportation in a pipe network are disclosed. Pressures and flow rates at a predetermined number of points in the pipe network which number is smaller than the number of demand nodes in the pipe network are detected, demand volumes at the demand nodes are estimated based on known flow and pressure balance requirements for the pipe network and the detected flow rates and pressures, and the flow transportation in the pipe network is controlled in accordance with the estimated demand volumes such that the pressures at the demand nodes are brought to a reference pressure so that the pressures at the demand nodes at points other than the predetermined points are also brought to the reference pressure.

Abstract: A method of controlling the duty ratio of operation of a solenoid control valve in a fluid passage to control the flow rate of fluid in the fluid passage to a desired value. A flow rate value range is divided into a plurality of flow rate value regions between first and second extreme flow rate values which the fluid can assume when the duty ratio assumes corresponding minimum and maximum values. A first predetermined duty ratio value is preset corresponding to each of the divided regions and dependent upon the magnitude of manufacturing variations of the duty ratio-to-flow characteristic of the valve. A second larger predetermined duty ratio value is preset corresponding to each of the divided regions.

Abstract: To measure the flow rate of a fluid in a pipe, a heat pulse is injected into the fluid by a heat pulse generator, and the time of flight of the pulse between the generator and a sensor is measured. Arrival of the pulse at the sensor is determined by detecting a selected temperature level of the ascending flank of the pulse, and a predetermined temperature level of the descending flank is then detected to initiate generation of the next subsequent pulse. Since the temperature of the descending flank generally represents the temperature of the fluid between the heat pulse generator and sensor, the technique ensures that the accuracy of each successive flow rate measurement is not affected by residual heat from the preceding measurement, and yet enables measurements to be obtained at maximum frequencies. In one embodiment the measurements are used to control the flow rate of the measured fluid, and in another the flow rate of fluid in one or more additional pipes.

Abstract: Apparatus and method for producing a slurry. The apparatus includes a slurry reservoir, a closed circuit and a pump for circulating slurry from the reservoir through the closed circuit and back to the reservoir. Means are provided for introducing both particulate and liquid materials into the closed circuit for forming the slurry. A first control circuit provides a particulate flow rate signal indicating the rate of flow of particulate material into the closed circuit. A flow meter provides a liquid flow rate signal indicative of the actual flow rate of liquid material into the closed circuit. A density measuring and control circuit measures the density of slurry flowing within the closed circuit and provides a density signal indicative of the difference between the measured density of slurry and a desired desity based upon data inputted to the density measuring and control circuit.

Abstract: Apparatus for combining fluid flows in variable proportions is adapted for blending an active constituent gas and a diluent gas to calibrate gas analyzers used in monitoring pollution.Diluent gas passes from source 34 through a downstream differential pressure regulator 17 and a constant flow restrictor 12 to outlet 14 which communicates with control port 20 of regulator 17. Active gas passes from source 35 through differential pressure regulator 23, through three fixed parallel flow restrictors 22, 29 and 30 to combine with the diluent gas upstream of restrictor 12. Control port 26 of regulator 23 communicates with the input to restrictor 12. Switching of valves 31, 32 and 33 varies the rate of flow along conduit 16 and hence the proportions of gases combined upstream of restrictor 12. Regulator 23 maintains flow along 16 substantially constant for given valve settings, and regulator 17 maintains flow along outlet 14 substantially constant despite changes in flow rate in the conduit 16.

Abstract: The method is based on the fact that the particular components are conveyed through separate pipes into a mixing chamber. By measuring the transit time in at least one of the pipes the flowrate can be measured. The flow in the other pipes which is in a fixed ratio to the first flow is then adjusted automatically. For measuring the transit time a heat pulse is injected in at least one of the pipes and the transit time of the heat impulse is measured. The so-measured transit time is converted into an inversely proportional voltage and the flowrate in the other pipes is adjusted proportionally to this voltage. An apparatus is provided for practicing the method. The apparatus comprises flow measuring elements which are electrical connected to control devices which operate flow control devices in the pipes leading to the mixing chamber.

Abstract: A method and apparatus for the diversion of fluid flow at reduced pressure out of a high pressure fluid delivery system when the discharge of the system is closed. A bypass valve having a movable piston oriented transverse to the flow direction and a slidable seal oriented parallel to the flow direction is located between the system pump and discharge. The movable piston has two working surfaces of different areas which define planes parallel to the flow direction so that the working surfaces and therewith the piston are generally responsive only to static fluid pressure. The slidable seal is responsive to dynamic fluid pressure so that when the discharge is closed and the dynamic fluid pressure thereby reduced, the seal moves to interrupt fluid communication between the two working surfaces of the piston.