A
(a) Write the differential equation and boundary conditions that govern the species A mass density distribution,
(b) What is the heat transfer analog to this problem? From this analog, write an expression for the average Sherwood number associated with mass exchange over the region
(c) Beginning with application of conservation of species to a differential control volume of extent
(d) Consider conditions for which species B is air at
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Fundamentals of Heat and Mass Transfer
- ANSWER this, please.With the formula derived and the conditions applied in problem statement # 1, calculate for the heavier liquidoverflow leg, the diameter, and the volume of the tank in separating liquid B from liquid A having densities of 1278kg/m3 and 794 kg/m3, respectively. The volumetric flow rate of the mixture entering the tank is 30 m3/hr and the viscosity of the lighter liquid (continuous phase) is the same as the viscosity of water @ 35oC. Volume of heavier liquid is twice the volume of the lighter liquid and having a tank diameter to height as 1:2 ratio. Assume for 10% from the tank volume allotted for the vapor space having a pressure of 50 kPa. REFERENCE: (problem 1) Derive a formula to calculate for the height, ZC of the heavier liquid overflow leg in a continuous vertical cylindrical decanter. The pressure at the discharge point of the heavier liquid is given as 90% of the pressure on top of the fluid mixture. Express the height of the heavier liquid as ZB and the…arrow_forwardAs a process engineer, you are designing a new drinking water treatment plant using conventional treatment process including Two Trains of Flocculators as follows: The design flow is 0.35 m³/s. The average temperature of water is 5°C with a dynamic viscosity, μ = 1.519 x 10-3 Pa.S and p = 999.967 kg/m³. The major target of the WTP is to remove color from water using alum as coagulant. GAvg 0 = 120,000. In each train of flocculators, it includes three same size compartments in series with the tappered velocity gradients G: 80, 50, and 20 Sec-¹. Length = Width = Depth for each Comparment. The type of impeller is axial-flow with three blades. The available impeller diameters are 1.0, 1.8 and 2.7 m. The water depth below the impeller, B = 1/3 H. H is the water depth in flocculator.arrow_forwardQ6/ It is required to enhance the wear resistance of steel part by Nitriding process. To perform such task, the nitrogen surface concentration must be increased to 0.5 wt% while the initial value was 0.002 wt%. The nitrogen gas with constant temperature is provided from external source. To optimize the diffusion process; the subsurface layer of 0.4 mm depth, must has nitrogen content of 0.1 wt%. Find out the required process temperature to accomplish this treatment at 1.6 hour. The values of activation energy and preexponential for the nitrogen in iron at this temperature are 76,150 J/mol and 3 x 107 m2/s, respectively. erf(z) erf(z) erf(z) 0.55 0.5633 1.3 0.9340 0.025 0.0282 0.60 0.6039 1.4 0.9523 0.05 0.0564 0.65 0.6420 1.5 0.9661 0.10 0.1125 0.70 0.6778 1.6 0.9763 0.15 0.1680 0.75 0.7112 1.7 0.9838 0.20 0.2227 0.80 0.7421 1.8 0.9891 0.25 0.2763 0.85 0.7707 1.9 0.9928 0.30 0.3286 0.90 0.7970 2.0 0.9953 0.35 0.3794 0.95 0.8209 2.2 0.9981 0.40 0.4284 1.0 0.8427 2.4 0.9993 0.45 0.4755…arrow_forward
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- The liquid food is flowed through an uninsulated pipe at 90 ° C. The product flow rate is 0.4 kg / s and has a density of 1000 kg / m³, specific heat 4 kJ / (kg K), a viscosity of 8 x 10-6 Pa s, and a thermal conductivity of 0.55 W / (m) K). Assume that the change in viscosity is negligible. The internal diameter of the pipe is 20 mm with a thickness of 3 mm made of stainless steel (k = 15 W / [m ° C]). The outside temperature is 15 ° C. If the outer convective heat transfer coefficient is 18 W / (m² K), calculate the heat loss at steady state per meter of pipe length. a.Find the convection coefficient in the pipe = AnswerW / m² ° C. b. Calculate heat loss per meter pipe length = Answerwatt.arrow_forwardB- A continuous separating tank is to be designed to follow after a water washing plant for liquid oil. Estimate the necessary area for the tank if the oil, on leaving the washer is in the form of small spherical particles 5.1 * 105 m diameter, the feed concentration is 4 Kg water to 1 Kg oil, and the leaving water is effectively oil free. The mass rate of feed of solids is 200 Kg/h. Viscosity of water = 0.7*10³ N.s/m². Density of water = 1000 Kg/m³. Pol 894kg/m²arrow_forwardBerlin, 1963, 67-77. 2B Problem 2: Average Velocity for Mass Balance in Flow down a Vertical Plate For a layer of liquid flowing in a laminar flow in the z direction down a vertical plate or surface, the velocity profile is: నgరా Where dis the thickness of the layer, x is the distance from the free surface of liquid toward the plate, and vz is the velocity at a distance x from the free surface. Consider the wall to have a depth of w in the y-direction and a length L in the z-direction. (a) Provide a sketch of the system described above with appropriate coordinates and origin point (b) What is the maximum velocity vz-max? Show that the expression you get has the units of velocity. (c) Derive the expression for the average velocity vz-av and relate that to Vz-max (d) Derive an expression for the total volumetric flow rate down the wall. Show that the expression you get has the units of m/s. (e) Calculate the shear acting on the x-surface at x=8. You are given the relationship between…arrow_forward
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