Bell mouth

About: Bell mouth is a research topic. Over the lifetime, 603 publications have been published within this topic receiving 1624 citations.

Centrifugal fan and ventilation fan

Abstract: A centrifugal fan includes: an impeller driven by a drive motor to rotate; a scroll casing including an inlet-port face having an opening and a wall portion having positions at which distances from an axis line that is a rotation center of the impeller differ from each other, and changing an air flow in a centrifugal direction generated by rotation of the impeller into an air flow in one direction; an air admitting portion including a bell mouth portion having a large-diameter side end placed on an inlet-air-flow upstream side of the inlet-port face; and a protruding portion extending from the air admitting portion in a direction orthogonal to the axis line, which is the rotation center of the impeller, and in a direction away from the rotation center and surrounding part of the bell mouth portion.

Outdoor unit for large size air-conditioner having decreased difference of flow distribution between upper and lower parts

Abstract: An outdoor unit for a large-sized air conditioner is provided to facilitate heat exchange at a lower section of a heat exchanger for obtaining enhanced heat exchange efficiency corresponding to the size of the heat exchanger, by having bell mouths with elongated vertical widths. An outdoor unit for a large-sized air conditioner comprises more than two bell mouths(35,45), a blower fan(30,40), and a partition wall for a flow guide(50). The bell mouths are indented on an upper surface(5) of a body unit(10). The blower fan is provided with the same numbers as the bell mouths and installed in the center of each bell mouth. The partition wall is downwardly extended in a predetermined height, from the position between the bell mouths adjacent the upper surface of the body unit to divide an upper section of internal space. Each width of the bell mouth is larger than a vertical width of each blower fan.

Experimental Study on Quadrilateral Floor Splitter for Reducing Sub-surface Vortices in Pump Sump

Abstract: An experimental investigation on the effective shape of a quadrilateral floor splitter to reduce sub-surface vortices and cavitation is performed. A test model sump was designed based on the Froude number similitude for the recommended structure layout by HI Standard. To obtain an effective shape of the splitter as an anti-vortex device, 3 types of quadrilateral submerged bar with different shape and dimension in sectional area are considered. From the experimental results with and without the splitter, it was confirmed that the installation of the anti-vortex device is very effective to reduce abnormal vortices including sub-surface vortices, pre-swirls and other undesirable hydraulic phenomena. Because of the splitter, sub-surface vortices under the bell mouth did not appear anymore and the swirl was dramatically weakened. The evaluation of the splitter was made by the measurement of swirl angles. Splitters with square sections showed partly large swirl angles exceeding the acceptable criteria of HI standard. Meanwhile, the splitter with trapezoidal section was showed swirl angle values of less than 5 degrees in all cases of pump operation. Among the 3 types of anti-vortex device, the trapezoidal splitter is the most effective one to suppress the vortices. It is very useful to reduce the occurrence of submerged vortices and to obtain stable inflow condition for designing a high performance pump sump.

Heat pump water cooler and water warmer

Abstract: PROBLEM TO BE SOLVED: To provide a heat pump water cooler and water warmer capable of performing a smooth draining of water while preventing liquid droplets of dew condensation water from being dispersed through rotation of an impeller of a blower fanSOLUTION: A tray member 42 arranged at an outdoor unit 2 collects at least a part of dew condensation water generated at a cold water or hot water circulation circuit 22 and drips it as liquid droplet from above a bell mouth 43 covering an outer circumference part of an impeller 10a of an outdoor fan 10 Then, in order to avoid splashing when the liquid droplets from above drop onto the bell mouth 43, the bell mouth 43 is provided with a water receiver part P and a flowing-down part R The liquid droplets dripped from the tray member 42 are received at the water receiver part P, the received liquid droplets flow down the flowing-down part R and are smoothly guided downward With this arrangement as above, it is possible to perform a smooth water discharging while preventing liquid droplets of dew condensation water from being dispersed under rotation of the impeller 10a of the outdoor fan 10SELECTED DRAWING: Figure 8

Batch drilling well wellhead design and assembling-disassembling method for modular drilling machine

Abstract: The invention discloses a batch drilling well wellhead design and assembling-disassembling method for a modular drilling machine. The wellhead design comprises the following design of supporting facilities: wellhead deck design, split bell mouth design, bell mouth fixing mode design, bell mouth fixed suspension design, grouting pipeline fixed design of bell mouths, reflux pipes and metering pumps, bell mouth variable diameter design, bell mouth variable diameter hoisting special tool design, telescopic inner and outer drum horn tube design, sealing design of special pressure plate sealing or gas inflatable pneumatic tires, lifting pipe hoisting special design, and special lifting pipe suspending channel design which are easy enough to operate. The batch drilling well wellhead design and matched wellhead assembling-disassembling method for the modular drilling machine provided by the invention can solve the problem of time consumption caused by frequently moving of a derrick in batch drilling operation of the modular drilling machine, reduce hoisting risks and risks of high falling objects caused by dissembling and throwing wellhead parts and optimize assembling and disassembling method of wellheads, and further are simple and convenient in design and simple in operation mode.