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A SIGNIFICANT NUMBER of the helicopters presently in the US Army inventory are inherently unstable and use pressurised hydraulic fluid in the hydromechanical flight control system. The development of a hydrofluidic stability‐augmentation system which can be integrated into the helicopter primary control system, offering promise of improved reliability, maintainability, and reduced cost over conventional electromechanical stability augmentation systems, has been accomplished.

Monodisperse microfluidic emulsions – droplets in another immiscible liquid – are beneficial to various technological applications in analytical chemistry, material and chemical engineering, biology and medicine. Upscaling the mass production of micron-sized monodisperse emulsions, however, has been a challenge because of the complexity and technical difficulty of fabricating or upscaling three-dimensional (3 D) microfluidic structures on a chip. Therefore, the authors develop a fluid dynamical design that uses a standard and straightforward 3 D printer for the mass production of monodisperse droplets.

The authors combine additive manufacturing, fluid dynamical design and suitable surface treatment to create an easy-to-fabricate device for the upscaling production of monodisperse emulsions. Considering hydrodynamic networks and associated flow resistance, the authors adapt microfluidic flow-focusing junctions to produce (water-in-oil) emulsions in parallel in one integrated fluidic device, under suitable flow rates and channel sizes.

The device consists of 32 droplet-makers in parallel and is capable of mass-producing 14 L/day of monodisperse emulsions. This convenient method can produce 50,000 millimetric droplets per hour. Finally, the authors extend the current 3 D printed fluidics with the generated emulsions to synthesize magnetic microspheres.

Combining additive manufacturing and hydrodynamical concepts and designs, the authors experimentally demonstrate a facile method of upscaling the production of useful monodisperse emulsions. The design and approach will be beneficial for mass productions of smart and functional microfluidic materials useful in a myriad of applications.

The purpose of this paper is to simulate the thermal performance of fluidic momentum controller (FMC) actuators in two case, with and without thermal distribution system on a three-axis configuration of FMC actuators to an orbital period of satellite. The results show the effectiveness of using a storage with FMC actuators.

One of the challenges during a satellite’s orbital mission is unpredictable external temperature perturbations. This system used as a collaborative thermal subsystem for microsatellite temperature passive control. The operating principles of the system are that each fluid rings are used in a microsatellite surface with pumps to stabilize the satellite. All fluid rings are connected to the satellite thermal distribution system (storage).

Simulation results show that with using of thermal distribution system, damping of satellite different surfaces temperature is rapidly possible to the event of thermal disturbances.

Numerical simulation is obtained by ANSYS Fluent software and pressure-velocity coupling is SIMPLE method and spatial discretization is second order accurate and first order in time, viscous model is k-e. In this regard, a solver algorithm is also developed.

In space research fields about FMC application as actuators to satellite system design, main goal is to research about role of this system to attitude and determination control system (ADCS) of satellites, and no study is performed on its role to satellite temperature damping. This study is exclusively simulated thermal distribution system (includes a storage and its connections) of a microsatellite equipped with FMC actuators. The idea of using a storage for FMC actuators is the innovative step of this research.

The purpose of this article is to present numerical investigations of flow control with piezoelectric actuators on a backward facing step (BFS) and fluidic vortex generators on a NACA0015 aerofoil for the reattachment and separation control through the manipulation of the Reynolds stresses.

The unsteady flow phenomena associated with both devices are simulated using Spalart–Allmaras-based hybrid Reynolds averaged Navier-Stokes (RANS)/large eddy simulation (LES) models (detached eddy simulation (DES), delayed detached eddy simulation (DDES) and improved delayed detached eddy simulation (IDDES)), using an in-house computational fluid dynamics (CFD) solver. Results from these computations are compared with experimental observations, enabling their reliable assessment through the detailed investigation of the Reynolds stresses and also the separation and reattachment.

All the hybrid RANS/LES methods investigated in this article predict reasonable results for the BFS case, while only IDDES captures the separation point as measured in the experiments. The oscillating surface flow control method by piezoelectric actuators applied to the BFS case demonstrates that the Reynolds stresses in the controlled case decrease, and that a slightly nearer reattachment is achieved for the given actuation. The fluidic vortex generators on the surface of the NACA0015 case force the separated flow to fully reattach on the wing. Although skin friction is increased, there is a significant decrease in Reynolds stresses and an increase in lift to drag ratio.

The value of this article lies in the assessment of the hybrid RANS/LES models in terms of separation and reattachment for the cases of the backward-facing step and NACA0015 wing, and their further application in active flow control.

Microfluidic or “lab‐on‐a‐chip” technology is seen as a key enabler in the rapidly expanding market for medical point‐of‐care and other kinds of portable diagnostic device. The purpose of this paper is to discuss two proposed packaging processes for large‐scale manufacture of microfluidic systems.

In the first packaging process, polymer overmoulding of a microfluidic chip is used to form a fluidic manifold integrated with the device in a single step. The anticipated advantages of the proposed method of packaging are ease of assembly and low part count. The second process involves the use of low‐frequency induction heating (LFIH) for the sealing of polymer microfluidics. The method requires no chamber, and provides fast and selective heating to the interface to be joined.

Initial work with glass microfluidics demonstrates feasibility for overmoulding through two separate sealing principles. One uses the overmould as a physical support structure and providing sealing using a compliant ferrule. The other relies on adhesion between the material of the overmould and the microfluidic device to provide a seal. As regards LFIH work on selection and structuring of susceptor materials is reported, together with analysis of the dimensions of the heat‐affected zone. Acrylic plates are joined using a thin (<10 μm) nickel susceptor providing a fluid seal that withstands a pressure of 590 kPa.

Microfluidic chips have until now been produced in relatively small numbers. To scale‐up from laboratory systems to the production volumes required for mass markets, packaging methods need to be adapted to mass manufacture.

A characteristic feature of LTCC is good workability. In some cases a LTCC‐based microsystem can be a good alternative to microsystems made in silicon or other technologies. Reasons for choosing LTCC‐Technology may be financial considerations or specific material properties. A main problem is to simplify a mechanical component in such a way, that it is possible to integrate this component in a planar structure with a small height in consideration of the restrictions of the LTCC‐Technology. In contrast to LTCC‐based substrates with only electrical circuits the integration of mechanical components make other demands on the different technological steps of the LTCC‐Process. In this paper some 3D‐structures made in LTCC‐like fluidic channels, membranes usable for micropumps or pressure sensors – and some aspects of required special technological demands are described.

The purpose of this paper is to report a simple, room temperature approach to assemble dense, vertically aligned single‐walled carbon nanotubes (SWNTs) between a chip and its substrate acting as a kind of thermal interface material by virtue of better mechanical and thermal properties.

Two silicon chips, with shallow trenches about 2 μm deep on the surface, were pressed together face to face with the trench direction perpendicular to each other. SWNT aqueous solution was driven into the gap between the two chips by capillary force. Later, the sample was baked to remove the moisture completely.

SWNTs beams were found to be assembled in the gap and have their two ends bonding with the interface of the two chips, respectively. The shear strength of the two chips was measured, and the thermal conductivity of the stacked chip‐SWNTs‐chip was tested using a laser flash method. In result, shear strength up to about 100 kPa, and an average thermal conductivity of 19.3 W·m⁻¹·K⁻¹ were demonstrated.

The paper proposes an approach to grown dense SWNT array bridging a chip and its substrate, and these SWNTs have potential capability to provide mechanical strength and higher thermal conductance instead of commercial thermal interface materials.

This paper aims to study the fluid flow and heat transfer within the Casson nanofluid confined between disk and cone both rotating with distinct velocities. For a comprehensive investigation, two distinct nano-size particles, namely, silicon dioxide and silicon carbide, are submerged in ethanol taken as the base fluid.

This paper explores the disk and cone contraption mostly encountered for viscosity measurement in various industrial applications such as lubrication industry, hydraulic brakes, pharmaceutical industry, petroleum and gas industry and chemical industry.

It is worth mentioning here that the radially varying temperature profile at the disk surface is taken into the account. The effect of prominent emerging parameters on velocity fields and temperature distribution are studied graphically, while bar graphs are drawn to examine the physical quantities of industrial interest such as surface drag force and heat transfer rate at disk and cone.

To the best of the authors’ knowledge, no study in literature exists that discusses the thermal enhancement of nano-fluidic transport confined between disk and cone both rotating with distinct angular velocities with heat transfer.

The purpose of this paper is to present the research activity and results to research and development society on the field of ceramic microsystems.

The chemical reactor was developed as a non-conventional application of low temperature co-fired ceramic (LTCC) and thick-film technologies. In the ceramic reactor with a large-volume, buried cavity, filled with a catalyst, the reaction between water and methanol produces hydrogen and carbon dioxide (together with traces of carbon monoxide). The LTCC ceramic three-dimensional (3D) structure consists of a reaction chamber, two inlet channels, an inlet mixing channel, an inlet distributor, an outlet collector and an outlet channel. The inlet and outlet fluidic barriers for the catalyst of the reaction chamber are made with two “grid lines”.

A 3D ceramic structure made by LTCC technology was successfully designed and developed for chemical reactor – methanol decomposition.

Research activity includes the design and the capability of materials and technology (LTCC) to fabricate chemical reactor with large cavity. But further dimensions-scale-up is limited.

The technology for the fabrication of LTCC-based chemical reactor was developed and implemented in system for methanol decomposition.

The approach (large-volume cavity in ceramic structure), which has been developed, can be used for other type of reactors also.