Natural or industrial flows of a fluid often involve droplets or bubbles of another fluid, pinned by physical or chemical impurities or by the roughness of the bounding walls. Here we study numerically one drop pinned on a circular hydrophilic patch, on an OSCILLATING incline whose angle is proportional to sin(ω t). The resulting deformation of the drop is measured by the displacement of its center of mass, which behaves similarly to a driven over-damped linear oscillator with amplitude A(ω ) and phase lag φ (ω ). The phase lag is O(ω ) at small ω like a linear oscillator, but the amplitude is O(ω − 1) in a wide range of large ω instead of O(ω − 2) for a linear oscillator. A heuristic explanation is given for this behaviour. The simulations were performed with the software Comsol in mode Laminar Two-Phase Flow, Level Set, with fluid 1 as engine oil and fluid 2 as water.

This paper presents an experimental study of the effect of a directionally porous wing TIP on the TIP vortex using particle image velocimetry (PIV) on a half wing model with NACA 653218 as its airfoil section. Four different configurations of the directionally porous wing TIP are tested. The vortex generated by the wing TIPs are examined at four different measuring planes downstream perpendicular to the flow axis. The flow field over the porous wing TIP surface along the streamwise direction is obtained as well to understand the effects of the porosity on the flow which in the end affects the vortex downstream. Furthermore, the aerodynamic performance of all different configurations is compared to study their effects on the aerodynamic coefficients of the wing. The results show a high reduction in vorticity, up to 90%; tangential velocity reduction up to 67% and a significant reduction in vortex circulation in the near-far field. Effect on the lift to drag ratio is up to 20 %.

Background and Aims: Numerous surgical procedures have been used to correct distal hypospadias, but in past 8 years repair of urethra with" Tubularized Incised Plate" technique or TIP has become prefered technique for distal hypospadias repair. In this study we report our experience about this procudure.Materials and Methods: This study was a descriptive retrospective study, patients, including 37 child boy with hypospadias with age range 9 months to 12 years, that between 2001 - 2003 years in Emam and Children hospitales of Tabriz under went to hypospadias repair with "TIP" procudure. All of the patients followed during hospitalization in first step and then 6 months post operation. This technique was the first repair to correct of hypospadias in all of these children.Results: Mean age of patients at the first repair was 44.19 months. The location of meatus was cronal in 2 patients, distal shaft in 27 patients, mid shaft in 5 patients and mega meatus with intact prepuce (MIP) in 3 patients. Mean operation time was 94 minutes. Mean hospitalization time was 5.9 days. 1 patient (2.70%) had bleeding from operation site during hospitalization. During follow up urethro cutaneus fistulas occurred in 3 patients (8%). During follow up all of the patients was voiding from a single urinary tract and in the straight stream.The total success rates of surgery was 92%. No significant difference in results was between this study and similar reports.Conclusion: Currently repair of urethra with TIP procudure is one of the most popular procudures for hypospadias repair. This procedure is potentially applicable in all cases of distal and mid shaft hypospadias.

Introduction: Today, we are seeing change in the manufacturing process of mechanisms as a multi-purpose device with the dramatic growth of technology. It both helps in saving space and the cost of the product decreases considerably. Today, due to the cost of providing places for jobs, smaller and more compact multifunctional devices are designed. The proposed device is a du-al-use Laboratory Mixer. This device is designed for mixing liquid with determined viscosity, which has various options to enhance the quality and comfort of the operator.Materials & Methods: The device uses a combination of two methods while the process of mixing is separate in other devices, i.e. the mixer device is either radial or OSCILLATING. One of the importing points in the design of the device is that both systems are combined in one device and it is equipped with control and timing speed system. So far, the roller or Rocker device have not been made and designed in Iran and they are built for the first time. Their main use is for professional mixing experiments in the laboratory of Immunology and medical diagnostics.Findings: The results of the electrical and mechanical performance of the device are acceptable according to the inventions used in various parts and it is economical.Discussion & Conclusion: We could significantly reduce blood clots while it is mixing up by designing the angle of the device. This problem is the result of blood into the vial with the vial cap that causes the so-called "lysis". Another achievement of this device is the combining of both the roller and Rocker devices which provides new mixing methods in the lab for operator.

Introduction & Objective: In most anatomic references, the shape of the lower lateral cartilage (LLC) is described as a two-dimensional structure. However, the authors have found different forms of LLC in at least 40% of their open rhinoplasty cases in the last 20 years. We found this cartilage to have a threedimensional hemispheric appearance that was connected to the upper lateral cartilage (ULC) at scroll area by an inward limb of this hemisphere. This inward limb may have an important role in producing asymmetry and flare of the nostril. Materials & Methods: The LLC of 286 patients was evaluated during open rhinoplasty over a two-year period, with the main focus on the shape of this structure, especially at the LLC-ULC junction (scroll area). Results: A dome-shaped appearance of the LLC was noted in 40.9% of cases, and 11.5% of cases had bilateral LLC variation. This different anatomic form was seen mostly in patients with a strong bulbous TIP, although it was observed less frequently in narrow nasal TIPs as well.Conclusions: At least one-third of the LLCs that were analyzed had a medial wall in addition to the lateral wall, which significantly increased the flare and recoil force of this structure. This makes this cartilage more redundant to reshaping procedures (straightening); thus, special attention must sometimes be paid to this common anatomic variation in order to produce symmetric nostrils and obtain a more aesthetically acceptable alar TIP.

This paper describes a preliminary investigation into the use of normal form theory for modelling large non-linear dynamic systems. Limit cycle oscillations are determined for simple two-degree-of-freedom double pendulum systems. Such a system is reduced into its centre manifold before computation of normal forms, which are obtained using a period averaging method applicable to non-autonomous systems and more advantageous than the classical methods. A good agreement was observed between the predicted results from the normal form theory and the numerical simulations of the original system.

One of the important ways of improving axial compressor performance is to control the TIP leakage flow near the endwall region. Numerical computations were conducted to investigate the impact of blade TIP suction on the axial compressor cascade performance in current paper. Three suction schemes located on the blade TIP with different chordwise coverage were investigated in total. The results show that the cascade overall performance can be effectively enhanced by the proper suction scheme on the blade TIP and the best scheme should be arranged at slightly downstream of the onset point of the TIP leakage vortex (TLV). The control effectiveness and mechanisms are different for the different suction schemes. For the suction scheme covering the starting point of TLV, the onset point of TLV is shifted downstream, while an additional induced leakage flow near the blade leading edge is generated resulting in the increase of mixing loss. It is more effective when the structure of the main TLV is destroyed and divided into different parts by applying the blade TIP suction arranged slightly behind the onset point of TLV. In addition, the blade loading is redistributed near the blade TIP after the blade TIP suction and the total pressure loss caused by the suction slots should also be considered in the design process.

The system consisting of two rigid bodies in a viscous fluid is considered. The main body with mass M is placed in a viscous incompressible fluid, and the body with mass m moves inside the main body. This system is known as vibrobot which can be used in arbitrary inspection fluid mechanic objects such as oil industries pipes and tanks, as well as marine industries, medicine, etc. In this paper, the interaction between the vibrobot and viscous fluid is studied to achieve the motion laws of the vibrobot with the harmonic oscillation of internal mass. Also the flow structure around vibrobot and its effects on the hydrodynamic force acting on the vibrobot are investigated. Analyses are carried out by direct numerical simulation of the vibrobot motion in a viscous fluid by OpenFOAM package. Calculations are performed for the following combinations of control parameters; The ratio of the viscous fluid mass to the vibrobot mass m_1=0.35, the ratio of the internal mass to the vibrobot mass m_2=0.325 and dimensionless oscillation frequency f=1.5, when Reynolds number takes values in the range of 50<Re<250. Calculations have been performed with different initial approximations, determined by different initial velocities of the incident flow.