Abstract: Methods and apparatus for a flow ratio controller are provided herein. In some embodiments, a flow ratio controller includes an inlet; a plurality of channels extending from the inlet to a corresponding plurality of outlets; a bypass pipe extending from each channel of the plurality of channels that diverts a small portion of a flow from that channel and then returns the small portion of the flow back to that channel; and a thermal mass flow meter coupled to the bypass pipe having a first temperature sensor, a second temperature sensor, and a heating element disposed therebetween. A controller is configured to determine a flow rate through each of the plurality of channels based on a measured temperature difference between the first temperature sensor and the second temperature sensor.

Abstract: A feed pump to increase the pressure in a line includes a pumping chamber for a pumping medium. At least one temperature sensor, which is arranged in the feed pump, is allocated to the pumping chamber and is in thermal contact with the pumping chamber for determining a temperature of the pumping medium in the pumping chamber. A temperature control device is allocated to the at least one temperature sensor and by which defined temperature conditions can be created in an area surrounding the at least one temperature sensor. An evaluation device to which the at least one temperature sensor is coupled for signal purposes uses the data from the at least one temperature sensor to determine whether pumping medium is flowing through the pumping chamber or not.

Abstract: A cooling circuit for a fuel cell includes at least one channel, a mechanical support, a first sensor, and a second sensor. Each channel is formed in a bipolar plate of the fuel cell, and is adapted to permit a cooling fluid to flow. The first sensor senses a flow rate of the cooling fluid. The second sensor senses an electrical conductivity of the cooling fluid. Both the first sensor and the second sensor are installed on the mechanical support.

Abstract: A gas distribution system may include a gas mass flow sensor with a resistive element configured to be heated, a thermally conductive shell surrounding the resistive element and heat-transfer control elements. The shell may include a leading surface oriented substantially orthogonal to a direction of gas flow. The heat-transfer control elements may be positioned to focus heat transfer from the resistive element through the leading surface of the shell so that a rate of heat transfer is independent from the variations in flow configuration.

Abstract: Microprocessor-based thermal dispersion mass flow meters (i.e., thermal anemometers) are described that use temperature sensing elements in its flow sensor probe(s) in addition to the two elements commonly used. Such systems allow for automatically managing changes in gas selection, gas temperature, gas pressure, and outside temperature. One mass flow meter described has a flow sensor with four temperature sensing elements, wherein one pair is provided in a temperature sensor probe and another pair in a velocity sensor probe. Another variation operates without a separate temperature sensor probe and integrates all function into a single three-sensor probe. Such a device may also be used in conjunction with a one- or two-sensor temperature probe.

Abstract: A temperature insensitive mass flow controller comprising a main flow line, a capillary tube coupled to the main flow line across a bypass a thermal sensing element coupled to the capillary tube and a mass flow controller housing adapted to at least cover the capillary tube. A first heat sink has been coupled to the mass flow controller internal to the mass flow controller housing and coupled to the capillary tube. The heat sink being adapted to control a temperature of a gas in the capillary tube.

Abstract: A liquid droplet measurement apparatus has: a first laser light source emitting a laser light; a first optical device which makes, in terms of a beam cross-section of the laser light, a beam width in a direction perpendicular to a direction of ejection of a liquid droplet, greater than a beam width in the direction of ejection of the liquid droplet, and makes light intensity of the laser light fall within a prescribed range within a range where variation in a position of the liquid droplet occurs in the direction perpendicular to the direction of ejection of the liquid droplet, at a position where the laser light from the first laser light source is irradiated onto the liquid droplet ejected; a first light receiving device which receives the laser light that has been irradiated onto the liquid droplet by the first optical device and generates a determination signal; and a first liquid droplet characteristics calculation device which calculates at least one of a volume of the liquid droplet and a velocity of t

Abstract: Systems and methods for measuring the flow of a liquid along a conduit are disclosed. A heat source applies thermal energy to a portion of a liquid flowing along a conduit thereby elevating its temperature. A light source generates a first beam that passes through the liquid in the conduit downstream from the position of application of the thermal energy and an optical detector receives this beam in combination with a second beam that is not passed through the liquid in the conduit and measures a change in intensity of a combined beam. The time required for the heated portion of the liquid to move from the point of application of thermal energy to the point at which the beam passes through the liquid is measured. This measured time, along with the distance of separation of the heat source and the optical sensing means permits calculation of the velocity of the liquid in the conduit.

Abstract: A device for measuring the flow rate of a fluid confined by a wall member, and wherein the device comprises contacting apparatus for contacting the wall member, the contacting apparatus being formed of a material having a first heat transfer coefficient so that heat may be exchanged between the wall member and the contacting apparatus. The device further comprises heating apparatus for supplying heat to and draining heat from the contacting apparatus so that heat is being supplied to the wall member when heat is being supplied to the contacting apparatus and so that heat is being drained from the wall member when heat is being drained from the contacting apparatus. Bridging apparatus for providing thermal contact between the heating apparatus and the contacting apparatus are provided.

Abstract: A sensor can be configured to generally include a flow channel block having a flow channel formed therein, and a sensor chip for sensing fluid flow, wherein a fluid in the flow channel surrounds the sensor chip. Alternatively, the sensor chip can be fastened at one side to a substrate and on another side of the substrate to a core tube inserted into the flow channel. This core tube provides electrical insulation and corrosion protection to the sensor chip, reduces flow noise, (and by the non-intrusive nature of the measurement) essentially eliminates the risk of fluid leakage, and maintains the fluid super-clean and contamination-free while improving structural integrity for the thermal measurements derived from the sensor chip. The use of such a core tube configuration also can protect the sensor from corrosion, radioactive or bacterial contamination, overheating, or freeze-ups.

Abstract: A non-intrusive sensor for measuring mass flow of a medium flowing through a tube comprises: a probe having a predetermined length disposed along an external wall of the tube; a heater for heating the probe at a first point along the length thereof; a first temperature measuring device disposed at the first point for measuring a temperature of the probe and for generating a first signal Th representative thereof; a second temperature measuring device disposed at a second point along the length of the probe for measuring another temperature of the probe and for generating a second signal Tt representative thereof; a third temperature measuring device disposed along the external wall of the tube a distance away from the probe for measuring an ambient temperature and for generating a signal Ta representative thereof; and circuitry coupled to the first, second and third temperature measuring devices for generating a mass flow signal based on a ratio of temperature differential signals (Th?Ta)/(Tt ?Ta).

Abstract: A mass fluid flow sensor for determining the amount of fluid inducted into an internal combustion engine, for example, is disclosed. The mass fluid flow sensor includes an external intake fluid temperature element which improves the accuracy of the mass fluid reading. An external cold wire element is further provided which improves response time. The mass fluid flow sensor has an improved aerodynamic design which provides a lower system pressure drop. A molded one-piece isolated jet nozzle having a hot element disposed therein is included in a fluid sampling portion. The fluid sampling portion has a tubular sampling channel, wherein the sampling channel has one bend having a constant bend radius. Consequently, an improved lower internal flow passage pressure drop is achieved. Additionally, an improved signal to noise ratio, as well as a larger dynamic range is an advantageous consequence of the present invention.

Abstract: A slosh suppressor prevents damage to electronic components and wire bonds of a circuit module contained in a circuit chamber formed by the housing of a sensor module. The circuit module is positioned within the circuit chamber and has a silicon gel layer positioned thereon for protecting the circuit module from the environment. A housing cover is structured to engage the sensor housing and close the circuit chamber. The housing cover has a projection extending into the circuit chamber and engaging the silicon gel layer to reduce vibration in the silicon gel layer and protect the circuit module.

Abstract: A mass fluid flow sensor for determining the amount of fluid inducted into an internal combustion engine, for example, is disclosed. The mass fluid flow sensor includes an external intake fluid temperature element which improves the accuracy of the mass fluid reading. An external cold wire element is further provided which improves response time. The mass fluid flow sensor has an improved aerodynamic design which provides a lower system pressure drop. A molded one-piece isolated jet nozzle having a hot element disposed therein is included in a fluid sampling portion. The fluid sampling portion has a tubular sampling channel, wherein the sampling channel has one bend having a constant bend radius. Consequently, an improved lower internal flow passage pressure drop is achieved. Additionally, an improved signal to noise ratio, as well as a larger dynamic range is an advantageous consequence of the present invention.

Abstract: A method and device, employing positive-temperature-coefficient material, for sensing plural properties of a fluid, such as temperature and flow rate. Can be used in a wind gauge or in a device for sensing position of mechanical elements such as valve diaphragms. Single sensor device, with energy and ohmic resistors, produces two voltages which completely characterize temperature and flow rate of fluid under study.

Abstract: A measuring instrument for measuring mass of a flowing medium in which a measuring body extends across the flowing medium and has a rectangular flow channel through which the medium flows. The flow channel has a constricted inlet, a central portion with parallel sides and a widened outlet. A measuring element is supported in the measuring body such that the medium flows thereon. The measuring element carries temperature and heating sensors.

Abstract: A mass fluid flow sensor for determining the amount of fluid inducted into an internal combustion engine, for example, is disclosed. The mass fluid flow sensor includes an external intake fluid temperature element which improves the accuracy of the mass fluid reading. An external cold wire element is further provided which improves response time. The mass fluid flow sensor has an improved aerodynamic design which provides a lower system pressure drop. Moreover, the sensor is smaller and lighter and has fewer parts, thus providing better manufacturability. A molded one-piece isolated jet nozzle having a hot element disposed therein is included in the fluid sampling portion. Consequently, an improved lower internal flow passage pressure drop is achieved. Additionally, an improved signal to noise ratio, as well as a larger dynamic range is an advantageous consequence of the present invention. The present invention further provides improved electromagnetic interference performance.

Abstract: A mass flow sensor is disclosed comprising: a heated probe having a predetermined length for disposition in the path of mass flow; at least two first temperature measuring devices disposed at different points along the probe length for measuring temperatures of the heated probe at such points in the presence of the mass flow; a second temperature measuring device for disposition in the path of mass flow for measuring the temperature of the mass flow; and a processing unit for determining mass flow as a function of the temperature measurements of the first and second temperature measuring devices.

Abstract: A sensor for measuring changes in mass air flow is described that uses one or more thermoelectric devices, each of which serves both as a heating element and as a differential temperature sensor. The thermoelectric device or devices are sandwiched between two surface plates. The sensor operates the device or devices in constant current or in pulsed current mode. The operation in constant current mode involves passing the current through one thermoelectric device to create a temperature differential between the two surfaces. A second thermoelectric device generates a voltage in response to the differential, the voltage being proportional to the air flow rate. In another embodiment, the device contains a single thermoelectric device that operates in a pulsed mode, first to create a temperature differential using an applied current, and then to measure the voltage. When the voltage reaches zero, the cycle is repeated. The cycle time determines the air flow rate.