Building acoustic beamformers is a problem whose solution is hindered by the wide-band nature of audible sound. In order to achieve a consistent directional response over a wide range of frequencies, a conventional acoustic beamformer needs a high number of discrete loudspeakers and be large enough to achieve a desired low-frequency performance. The acoustic beamformer design described in this ...

the effect of γ-al2o3 nanoparticles on heat transfer rate, baffle spacing and pressure drop in the shell side of small shell and tube heat exchangers was investigated numerically under turbulent regime. γ-al2o3-water nanofluids and pure water were used in the shell side and the tube side of heat exchangers, respectively. since the properties of γ-al2o3-water nanofluids were variable, they were ...

OBJECTIVES The total cavopulmonary connection (TCPC), the current palliation of choice for single-ventricle heart defects, is typically created with a single cylindrical tunnel or conduit routing inferior vena caval (IVC) flow to the pulmonary arteries. Previous studies have shown the haemodynamic efficiency of the TCPC to be sub-optimal due to the collision of vena caval flow, thus placing an ...

This paper presents a method for calculating the directivity of the radiation of sound from a panel or opening, whose vibration is forced by the incidence of sound from the other side. The directivity of the radiation depends on the angular distribution of the incident sound energy in the room or duct in whose wall or end the panel or opening occurs. The angular distribution of the incident sou...

Presence of salts in water has been one of the biggest problems of industrial equipment such as evaporators, boilers, and pipes. These salts gradually form scales on evaporators and boilers tubes and reduce their efficiency. Pretreatment processes are conducted to remove these salts; with sedimentation tanks being one of the essential equipment used in these processes. This study numerically si...

The demand for liquid carriers, such as liquefied natural gas (LNG), has increased in recent years. One of the most common types LNG carriers is membrane type, which often built by a shipyard with prismatic tank shape. This carrier commonly known its effective ways to mitigate sloshing using baffle. Therefore, this study was performed evaluate vertical and T-shape baffles. conducted 25% 50% fil...

We report a case of a 27-year-old man with Senning repair of D-transposition of the great arteries. A dual-chamber pacemaker was placed for syncope due to sinoatrial node dysfunction 3 years before this presentation. He had no further syncope but complained of dyspnea on exertion and mild exercise intolerance. A routine chest x-ray and transthoracic echocardiography suggested the presence of a ...

Equations describing the radiation characteristics of a rigid disk in a finite open baffle are derived using a method similar to that used by Streng for a circular membrane based upon the dipole part of the Kirchhoff–Helmholtz boundary integral formula. In this case, however, a power series solution to the radiation integral is derived in order to eliminate the need for numerical integration. H...

Forty-nine patients with transposition of the great arteries who underwent a Mustard atrial baffle repair between 1964 and 1971 were assessed late postoperatively. There have been five late deaths: two related to baffle obstruction, two from noncardiac causes, and one sudden and unexpected. Hemodynamic data were available in 42 patients and autopsy in four. Obstruction of the lower venous chann...