Micro Coriolis mass flow sensor for chemical micropropulsion systems

We have designed a micromachined micro Coriolis flow sensor for the measurement of hydrazine (N2H4, High Purity Grade) propellant flow in micro chemical propulsion systems [1]. The sensor measures mass flow up to 6 mg/s for a single thruster or up to 24 mg/s for four thrusters. The sensor will first be used for measurement and characterization of the micro thruster system in a simulated space vacuum environment. Integration of the sensor chip within the micro thruster flight hardware will be considered at a later stage. The new chip has an increased flow range because of an integrated on-chip bypass channel

Micro Coriolis mass flow censor with extended range for a monopropellant micro propulsion system

We have designed and realised a micromachined micro Coriolis flow sensor for the measurement of hydrazine (N2H4, High Purity Grade) propellant flow in micro chemical propulsion systems. The sensor should be able to measure mass flow up to 6 mg/s for a single thruster or up to 24 mg/s for four thrusters. The sensor will first be used for measurement and characterisation of the micro thruster system in a simulated space vacuum environment. Integration of the sensor chip within the micro thruster flight hardware will be considered at a later stage. The new chip has an increased flow range because of an integrated on-chip bypass channel. First measurement results have demonstrated an increase in flow range which corresponds well to the designed bypass ratio

A compact micro Coriolis mass flow sensor with flow bypass for a monopropellant micro propulsion system

We have designed, fabricated and tested a micromachined Coriolis flow sensor for the measurement of hydrazine (N2H4) propellant flow in a micro chemical propulsion system (uCPS). The sensor will be used for measurement and characterization of the uCPS in a simulated space vacuum environment. To reach the required flow range a bypass system is integrated. Initial measurements demonstrate an increase of the flow range in accordance with the designed bypass ratio. The sensor is operated as a two-port resonator in an oscillator circuit to improve frequency stability

Single chip flow sensing system with a dynamic flow range of more than 4 decades

We have realized a micromachined single chip flow sensing system with an ultra-wide dynamic flow range of more than 4 decades, from less than 0.1 up to more than 1000 μl/h. The system comprises both a thermal and a micro Coriolis flow sensor with partially overlapping flow ranges

A novel capacitive detection principle for Coriolis mass flow sensors enabling range/sensitivity tuning

We report on a novel capacitive detection principle for Coriolis mass flow sensors which allows for one order of magnitude increased sensitivity. The detection principle consists of two pairs of comb-structures: one pair produces two signals with a phase shift directly dependent on the mass flow, the other pair is used to cancel the actuation signal. This results in larger phase shifts for the same mass flows. The range and sensitivity of the sensor can be tuned by changing the amount of cancellation of the actuation frequency, e.g. the size ratio between the comb-pairs

A versatile technology platform for microfluidic handling systems, part I:fabrication and functionalization

Many microfluidic devices are made using specialized fabrication processes, limiting the ability to integrate those devices on the same chip. In this paper, a versatile technology platform is presented that allows for integration of many different devices. It provides a method to design channels in a wide range of sizes and shapes with different functionalization options in close proximity to the fluid in the channels. The latter includes release of the channels for thermal isolation or mechanical movement and metal or piezoelectric layers for actuation and read-out. The channel walls are made using silicon-rich silicon nitride to provide durable, strong, chemically inert and thermally stable channels directly below the substrate surface