Why does the viscosity of a gas generally decrease with decreasing temperature whereas for a liquid its viscosity generally increases? Calculate and plot using Matlab the variation in the coefficient of dynamic viscosity of air in USC units from 35•F to 120•F. Sutherland's Law can be expressed as 1.5 T To+S µ= µ0 То To T+S

Why does the viscosity of a gas generally decrease with decreasing temperature whereas for a liquid its viscosity generally increases? Calculate and plot using Matlab the variation in the coefficient of dynamic viscosity of air in USC units from 35•F to 120•F. Sutherland's Law can be expressed as 1.5 T To+S µ= µ0 То To T+S

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.13P: 5.13 The torque due to the frictional resistance of the oil film between a rotating shaft and its...

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The Table below shows the following data for a fluid to be constant temperature: du/dy (rad*s-1) 0,2 0,4 0,6 0,8 (N*m-2) 1,0 1,9 3,1 4,0 (a) Determine the behavior of the fluid and its viscosity. (b) Explain why the viscosity of a liquid decreases while the viscosity of a gas increases with increasing temperature.
According to the Newton's cooling law, the temperature of any substance is directly related to the distinction between the substance temperature and its environment (ambient) temperature dT =-k(T – T,)k(T-T) dt where Tis the substance temperature (C) T is the time (minute) k is constant T. is environmental temperature A casting ladle of molten metal has 290 °C, By using Euler methodology, evaluate the temperature from t=0 to 35 min with a step size of 2 min. If, T, is 25°C and k is 0,009/min.
For most gases at standard or near standard conditions, the relationshipamong pressure, density, and temperature is given by the perfect gasequation of state: p = ρRT, where R is the specific gas constant. For airat near standard conditions, R = 287 J/(kg · K) in the International System of Units and R = 1716 ft · lb/(slug · ◦R) in the English Engineering System of Units. Using the above information, consider the following two cases: a. At a given point on the wing of a Boeing 727, the pressure andtemperature of the air are 1.9 × 104 N/m2 and 203 K, respectively.Calculate the density at this point.b. At a point in the test section of a supersonic wind tunnel, the pressureand density of the air are 1058 lb/ft2 and 1.23 × 10−3 slug/ft3,respectively. Calculate the temperature at this point.
The kinematic viscosity of liquid oil is 20 stoke and relative density = 0.85. Find the dynamic viscosity of this liquid oil in Sl and British systems. (1 stoke = 1 cm/s, 1m 3.28 ft, 1ft 30.48 cm and 1kg = 2.2 lb). Choose the correct answer: a- In SI system 25 kg/m.s and in British system 16.6 Ib/ft.s b- In SI System 17 kg/m.s and in British system 1.17 Ib/ft.s c- In Sl system 20 kg/m.s and in British system 8.15 Ib/ft.s
%AY |I1, 76% fTV s INTV Uo 10:21 یلیجرام 2.pdf Q1 1. How can recognize an extensive or intensive properties such as density, colour of gold, Volume of water in a graduated cylinder. 2. Drive the relation 1-x = Vavg - 3. A glycerin pump is powered by a 5-kW electric motor. The pressure differential between the outlet and the inlet of the pump at full load is measured to be 211 kPa. If the flow rate through the pump is 18 L/s and the changes in elevation and the flow velocity across the pump are negligible, the overall efficiency of the pump is (a) 69 percent (b) 72 percent (c) 76 percent (d) 79 percent (e) 82 percent. Q2 1. While solving a problem, a person ended up with the following equation at some stage: E 25 kJ +7 kJ/kg where E is the total energy and has the unit of kilojoules. Determine how to correct the error and discuss what may have caused it. 2. Define isolated system, specific gravity and thermal equilibrium. 3. Initially P-400 kPa and T-400 °C, as shown in FigQ2-1. What is…
A graduate student wants to use van der Waals' equation to express the pressure-volume- temperature relations for a gas. Her project requires a reasonable degree of precision in the p-V-T calculations. Therefore, she made the following experimental measurements with her setup to get an idea of how easy the experiment would be: Temperature, K Pressure, atm Volume, ft'/lb mol 273.1 273.1 200 1.860 1000 0.741 Determine values of constants a and b to be used in van der Waals' equation that best fit the experimental data.
You have been moved into the laboratory for the fluid testing for hydraulic devices, where your job is to illustrate the results of a viscosity test on a Newtonian fluid at various temperatures and explain discrepancies after completing the following given data-sheet in Table A. A considerable amount of research has been carried out in an attempt to understand the exact nature of the temperature variation of viscosity. One relatively simple model assumes that the viscosity obeys an 'Arrhenius-like' equation of the form n = Xe(k)r Хе --------Equation 1 where X = 1.7419 and (E/R) = -0.018 are constants for a given fluid. You are required to carry out appropriate calculations on the effect of changes in temperature given in table A by using equation 1 for Ethanol on the viscosity of a fluid. Table A NO Temperature viscocity n T°C cP 10 3 20 30 40 6. 50 7 60 8. 70 2. 4) 5.
Q1. Honey is a very widely used ingredient in cooking all around the world. Many commercial honey manufacturers heat treat honey to remove harmful bacteria that may be present. The density and viscosity of the honey varies with temperature, as shown in table 1. Temperature K 293 298 303 308 313 318 323 Density kg/m³ 1403 1398 1393 1388 1383 1378 1373 Viscosity Pas 55.66 46.45 37.99 30.28 23.32 17.11 11.65 Table 1: Fluid properties of honey. A particular processing facility heats and sterilises 500 kg of unprocessed honey every 30 minutes. The unpro- cessed honey is stored in large vats, then pumped though pipes into heating units before being pumped through another pipe to be bottled. The pipe carrying the honey from a storage container, which is 11 m tall, to a heating unit is 5 m long and has a diameter of 10 cm. Prior to being heated the honey is kept at 25°C. (a) What is the pressure difference between the top and bottom of a storage vat when it is full? (b) What is the volume flow…
The heat flux for stable film boiling on the outside of a horizontal cylinder or sphere of diameter D, in m, is given below. What should be the value of "n", for the equation above to be dimensionally consistent? Use dimensional analysis: q=heat flux, W m² W k = thermal conductivity of vapor, 'm °C hgf - [g kỷ Pv(P₁ − Pv)[hfg + 0.4 Cpv (Ts − Tsat)]] à = Cf MyD (Ts - Tsat) Pv = density of vapor, P₁ = density of liquid,- kg m³ kg 'm³ Cpv = enthalpy of vaporization, kg g = gravitatioinal acceleration, C = experimental constant, dimensionless m J kg °C Ts = surface temperature of the heater, °C Tsat = saturation temperature of vapor, °C kg Hv = viscosity of vapor, ms = specific hear of vapor, (Ts - Tsat)
Assignment 3 On Viscosity Calculation - Word TOUT REFERENCES MAILINGS REVIEW VIEW Hyperlink P Bookmark tArt Chart Screenshot Apps for Office Online Video Cross-reference Comment Header Footer Page Number Text Quick WordA Box Parts - ns Apps Media Links Comments Header & Footer (2) Referring to the following figure, the distance between plates is Ay = 0.5 cm, Av: = 10 cm/s, and the fluid is ethanol at 273 K having a viscosity of 1.77cp (0.0177 g/cm s). (a) Calculate the shear stress ty and the velocity (b) gradient of shear rate -/dy using cgs units. (c) Repeat using SI units. A Torce Fdshear berween teoparailel plates
valg, (21535mm 1.15 The pressure difference, Ap, across a partial blockage in an artery (called a stenosis) is approximated by the equation μV Ap - K. 4 + K.(A-1) pv² = K₂ A s.r to zogy nish190 32\V as bonb dignol a 3 basiy noft where V is the blood velocity, u the blood viscosity (FL-2T), p the blood density (ML), D the artery diameter, Ao the area of the unobstructed artery, and A, the area of the stenosis. Determine the dimensions of the constants K, and K. Would this equation be valid in any system of units?
The Reynolds number is a dimensionless group defined for a fluid flowing in a pipe as Re = Duplu where Dis pipe diameter, u is fluid velocity, p is fluid density, and u is fluid viscosity. When the value of the Reynolds number is less than about 2100, the flow is laminarthat is, the fluid flows in smooth streamlines. For Reynolds numbers above 2100, the flow is turbulent, characterized by a great deal of agitation. Liquid methyl ethylketone (MEK) flows through a pipe with an inner diameter of 2.067 inches at an average velocity of 0.48 ft/s. At the fluid temperature of 20°C the density of liquid MEK is 0.805 g/cm? and the viscosity is 0.43 centipoise [1 cP = 1.00 x 10-³ kg/(m-s)]. Without using a calculator, determine whether the flow is laminar or turbulent. Show your calculations.