14-51 A local ventilation system (a hood and duct system) is used to remove air and contaminants from a pharmaceutical lab (Fig. P14-51). The inner diameter (ID) of the duct is D = 150 mm, its average roughness is 0.15 mm, and its total length is L = 24.5 m. There are three elbows along the duct, each with a minor loss coefficient of 0.21. Literature from the hood manufacturer lists the hood entry loss coefficient as 3.3 based on duct velocity. When the damper is fully open, its loss coefficient is 1.8. The minor loss coefficient through the 90° tee is 0.36. Finally, a one-way valve is installed to prevent contaminants from a second hood from flowing "backward" into the room. The minor loss coefficient of the (open) one-way valve is 6.6. The performance data of the fan fit a parabolic curve of the form
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Fluid Mechanics: Fundamentals and Applications
- y aer. A Pitot tube is used to measure the air flow rate in a eircular duct 8.5 m I.D. The "riowing air temperature is 65.5°C. The Pitot tube is placed at the center of the duct and the reading R on the manometer is 1.2 cm of water. A static pressure measurement obtained at the Pitot tube position is 2.0 cm of water above atmospheric. Take Cp 0.98,9ter ase press u = 2.03 x 10 Pa.s, if U- Ux ( 1-0.17). Calculate The velocity at the center and the average velocity. The volumetric flow rate of the flowing air in the ductarrow_forwardA local ventilation system (a hood and duct system) is used to remove air and contaminants from a pharmaceutical lab (Fig. 1). The inner diameter (ID) of the duct is 129 mm, its average roughness is 0.15 mm, and its total length is L = 24.5 m. There are three elbows along the duct, each with a minor loss coefficient of 0.21. Literature from the hood manufacturer lists the hood entry loss coefficient as 3.3 based on duct velocity. When the damper is fully open, its loss coefficient is 1.8. The minor loss coefficient through the 90° tee is 0.36. Finally, a one-way valve is installed to prevent contaminants from a second hood from flowing “backward” into the room. The minor loss coefficient of the (open) one-way valve is 6.6. The performance data of the fan fit a parabolic curve of the form Havailable = H0 - aV2, where shutoff head H0 = 60.0 mm of water column, coefficient a = 2.50 x 10-7 mm of water column per (Lpm)2 ,available head Havailable is in units of mm of water column, and…arrow_forwardof áir 12.8/ A radial bush seal consists of a cylinder with an inner radius of 20 mm and an outer radius of 40mm. The axial gap is 0.2mm. Determine the flow rate of oil through the clearance if the pressure inside the cylinder 1Is 6 bar and the pressure outside the cylinder is 5.2 bar. Take the viscosity of oil as 0.022 Pa s.arrow_forward
- Q-2 ) ) A boiler house has natural draught chimney of 20 m height. Flue gases are at temperature of 380°C and ambient temperature is 27°C. Determine the draught in mm of water column for maximum discharge through chimney and also the air supplied per kg of fuel. Ans. [11.77 mm of water, 11.32 kg/kg of fuelarrow_forwardthe tube length is 1m.arrow_forward# 8-34. A 12 in diameter galvanized steel (smooth) straight duct section conveys air at 1000 ft /min. It is 100 ft long. a. Determine the pressure loss, in inches of w.c. b. Determine the average velocity of air flowing through the duct. c. Identify a cost-effective rectangular duct section with an equivalent pressure loss that has a side depth of 8 in.arrow_forward
- O WHATSAPP now Malek @ MENG370 Lab - Spring "O A aw D T me Te T00... Not yet answered Question 7 Marked out of 10 In ideal case and knowing that the area of the Venturi at the inlet and outlet is the same, the pressure head at the inlet and outlet of the Venturi will: Select one: a. Remain constant b. It depends on the velocity of water c. Increase d. Decrease Clear my choice Not yet answered Question 8 Marked out of 10 IIarrow_forwardlast three digits of your number for the upstream pressure: 754arrow_forwardSelect duct sizes for the rectangular duct system shown in the Figure, using the equal friction method. The total pressure available for the duct system is 0.12 in. wg (30 Pa), and the loss in total pressure for each diffuser at the specified flow rate is 0.02 in. wg (5 Pa). Assume the velocity in mean duct 600 fpm. 150 che 25 Boo ae und torectang a5On e S. 150 ct 0.095 mi 071 15marrow_forward
- State the three characteristics of each of the following I. Laminar II. Turbulentarrow_forwardA simply supported E C Search Textbook Solu My Questions | bartle s://ethuto.cut.ac.za/ultra/courses/_9063_1/cl/outline v Question Completion Status: The temperture e, radius The thro and of a pipe with inner 02 and outer radius are given by -In () 2 пkL and ®2 = Incr2) 2 пkL i= 1 whe where Q is the heat transfer rate, L is the length the of the pipe and k is thermal conductivity. tem The answer of e,-02 Mak A In 2 пkL A 12 01-02: In (r-r2) 2 пkL | 2 In 2 пkL C C D None of the above is correct V D N A. Option A is correct S. B.arrow_forwardThermal power plant burns 200 kilolitres diesel per day. In ideal conditions, burning of 1.0 kg diesel requires 14.2 kg of air. Parallel plate type ESP is installed to remove the particulates. If the height of channels is 4.5 m and the spacing between electrodes is 0.25 m, calculate: (i) Flue gas discharge in m3 per day (ii) The number of channels required (iii) Number of discharge electrodes provided (iv) Number of chambers requiredarrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning