Related papers: Optimal standoff distance for a highly focused mic…
The development of needle-free drug injection systems is of great importance to global healthcare. However, in spite of its great potential and research history over many decades, these systems are not commonly used. One of the main…
Injecting with needles causes fear, pain and contamination risks. Billions of injections every year also cause environmental burden in terms of material consumption and waste. Controlled microfluidic-jet injection systems offer a…
This study compares the penetration characteristics of impact-induced jets with those of laser-induced jets, focusing on the underlying penetration mechanism rather than device performance for needle-free injection. Using an impact-induced…
Needle-free injector technology (NFIT) has drawn attention due to their advantages. By using NFIT, it can be used several time unlike a conventional needle. Also, it makes patients free from pain. Since NFIT by jet injection is achieved by…
The amount of air entrained by vertical water jets impacting a large pool is revisited. To test available phenomenological models, new data on the jet deformation at impact and on the entrained air flow rate were collected both on a…
This paper describes a simple yet novel system for generating a highly viscous microjet. The jet is produced inside a wettable thin tube partially submerged in a liquid. The gas-liquid interface inside the tube, which is initially concave,…
In this paper, we have experimentally, numerically and theoretically investigated the water jet cleaning process. Very high speed water jets (~80-200 m/s) are typically used in such cleaning operations. These jets diffuse in the surrounding…
High speed imaging was used to capture the fast dynamics of two injection methods. The first one and perhaps the oldest known, is based on solid needles and used for dermal pigmentation, or tattooing. The second, is a novel needle-free…
The mechanics of puncture and soft solid penetration is commonly explored with the assumption of frictionless contact between the needle (penetrator) and the specimen. This leads to the hypothesis of a constant penetration force.…
In this paper we investigate the mechanical problem of piercing a soft solid body with a needle. This phenomenon is controlled by the critical condition of needle insertion. Needle insertion involves physical and geometrical nonlinearities…
We present physics-based nozzle design rules to achieve high-throughput and stable jetting in drop-on-demand liquid metal 3D printing. The design rules are based on scaling laws that capture the change of meniscus oscillation relaxation…
The development of needle-free injection systems utilizing high-speed microjets is of great importance to world healthcare. It is thus crucial to control the microjets, which are often induced by underwater shock waves. In this contribution…
This paper investigates the relationship between the contact angle of a spherical bubble attached to a tube submerged in a container and the jet speed induced by an impulsive acceleration at its base. While it has been well established that…
The base of a jet impinging on an ultrapure water bath is studied experimentally. At the impact point, a train of capillary waves develops along the jet. By performing Particle Tracking Velocity measurements, we show that there is a…
High speed microfluidic jets can be generated by a thermocavitation process: from the evaporation of the liquid inside a microfluidic channel, a rapidly expanding bubble is formed and generates a jet through a flow focusing effect. Here, we…
The stability of high-speed liquid jets is crucial for applications ranging from precision printing to needle-free drug delivery, yet it is fundamentally limited by capillary-driven breakup. A common strategy to stabilize jets is to use…
We conduct systematic experiments to investigate the dynamics of liquid jet breakup and the resulting droplet size distribution, emphasizing the influence of liquid jet velocity and needle exit diameter. We precisely control jet formation…
Impulsively generated focused jets play a significant role in various applications, including inkjet printing, needle-free drug delivery, and microfluidic devices. As the demand for generating jets and droplets from medium to highly viscous…
Numerical solutions of high-speed microdroplet impact onto a smooth solid surface are computed, using the interFoam VoF solver of the OpenFOAM CFD package. Toward the solid surface, the liquid microdroplet is moving with an impinging gas…
Breakup of a liquid jet in a high speed gaseous crossflow finds wide range of engineering and technological applications, especially in the combustors of the gas turbine engines in aerospace industry. In this study, we present…