Q. A perforated plate has holes of diameter dₙ arranged in a pitch pₕ. Each hole has a tube of I.D. dₜ passing through it. The ligament efficiency is given by

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Q. __________ is the determining factor for the number of bubble caps to be used per tray.

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Q. Pick out the wrong statement about distillation operation

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Q. Tube wall thickness depends on the cor-rosiveness of the fluids and their operating pressure & temperature and is specified by Birmingham wire gauge (B.W.G)-a number which varies from 8 to 18 with the numbers 14 and 16 being more commonly used. Outside diameter of tubes varies from about 15 to 50 mm; however a tube of less than __________ mm outside diameter is generally not recommended for fouling fluids.

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Q. Angled baffles are preferred in the agitation tank to control the swirling action; if the viscosity of the liquid to be mixed is about 200 poise. However, the baffle may be completely eliminated for mixing liquids having viscoisty above __________ poise.

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Q. Ratio of tube length to shell diameter for a shell and tube heat exchanger is

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Q. The dust collection efficiency of a cyclone separator

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Q. In a shell and tube heat exchanger, the overall heat transfer co-efficient is proportional to the tube side (volumetric flow rate)^0.8. This is valid, only when the ratio of the tube side film resistance to the total resistance is almost equal to

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Q. For a given fluid, as the pipe diameter increases, the pumping cost

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Q. Maximum acceptable total liquid gradient over a tray is about __________ mm.

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Q. In case of a 'thin' pressure vessel, the ratio of its diameter to wall thickness is

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Q. High pressure fluid in a shell and tube heat exchanger should preferably be routed through the

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Q. Bubble cap tray is the most commonly used tray in large distillation column, because

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Q. In the design of a paddle agitator, the ratio paddle dia/tank dia is normally taken as

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Q. The design stress, which is more than the damaging stress, is the least unit stress that will render a member unfit for service before the end of its normal life. The design stress factor or factor of safety indicates the margin between design stress and the __________ stress.

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Q. Hole diameter of the seive trays in the distillation column ranges from __________ mm.

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Q. Factor of safety (i.e., overdesign factor) in heat transfer equipments is about __________ percent more than the actual/theoretical design factor.

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Q. In actual operation of distillation column, the vapour is not distributed uniformly among the bubble caps, primarily because of the

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Q. The minimum shell thickness for tank ≤ 15 metres diameter is limited to __________ mm, for reasons of elastic stability.

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Q. If 'D' is the inside diameter of the shell of a shell and tube heat exchanger, then the baffle spacing is usually in the range of

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