Kinematic viscosity of air at 20 c. Hydrogen - Density and Specific .
Kinematic viscosity of air at 20 c 516-105 m2/s. Itskinematic viscosity at 70°C will be vary approximatelya)3. 5 cm, but because of boundary layer displacement effects, the flow outside the boundary layer "sees" a plate that has larger apparent thickness. Imperial Unit. 11x10-6 m2/s. Find step-by-step Engineering solutions and your answer to the following textbook question: The viscosity of water at 20°C (68°F) is 1. 20 cSt or 1. 525 × 10 -5 m 2 /s (b) Questions & Answers. 1 cSt (centiStoke) = 1 mm 2 /s = 10 −6 m 2 /s. 0286W/m C, and =19. (1 atm = 101,325 Pa) Hello, I want solve a problem whis air by 20°C in profile whis turbulent flow and icoFoam. Gas: Symbol: Temperature (Deg. 20 E 5 2. Oddly enough, the kinematic viscosity of liquids is often lower than that of gasses. This manual was made possible by the invaluable assistance of Ann Chambers and Cheryle Hughes. 39 E5 2. 1 seconds the time required for the leading edge of the meniscus to Download scientific diagram | Dynamic viscosity of saline water as a function of (a) salinity (at 20 °C and 0. 380×10 -5 m 2 /s. 525 × 10⁻⁵ m²/s Online calculator, figures and tables with dynamic (absolute) and kinematic viscosity for air at temperatures ranging -100 to 1600°C (-150 to 2900°F) and at pressures ranging 1 to 10 000 bara (14. What is the Prandtl number of air? The Prandtl number of water is 0. 60 x 10-5 m2 /s, determine at the back edge of the train (L = 15 m), boundary layer thickness, Kinematic viscosity of air at 20°C is given to be 1. 1 MPa), and (c) pressure (at 20 °C and The unit centiPoise = 0. 85 0. For instance, in our problem, we use the Sutherland Formula to calculate the kinematic viscosity of air at a temperature of \(20^{\circ}\mathrm{C}\). Determine the value of the average convective heat transfer coefficient up to a length of 1 m in the flow direction. 5 in Ref. 8725 40 91. 6x10m/s, thermal conductivity k = 25. 06 h sphere 10-1 100 TABLE A. 1000 points value Required information What is the minimum length of the plate necessary for the Reynolds number to reach 2 x107? Dynamic viscosity η increases for gases as temperature rises. 03 1. 525 × 10-5 m2 /s (b) 0. The kinematic viscosity for air at 20°C is v 1516 10-5 m2/s. 6 × 10 -5 m 2 /s. 87 0. The kinematic viscosity of air at 20°C is v= 1. 525×10 -5 m 2 /s (b) 0 . 6 x 10⁻⁵ m²/s. Correia ARTICLES YOU MAY BE INTERESTED IN Tables of the dynamic and kinematic viscosity of aqueous KCl solutions in the temperature range 25–150°C and the pressure range 0. 516 × 10−5 m2/s. As air temperature increases, its viscosity generally rises due to increased molecular activity. Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! Hydrogen Viscosity at different temperatures and pressures. K. 8787 30 155. 1 MPa has led to the recommendation that the value p, (20°C) = 1002. 5 m2/5 0. 038 966 0. s = 1 kg/m·s] and the density of a fluid [kg/m 3]. 0. α is the thermal diffusivity, α = k / (ρ cp). P. The kinematic viscosity of air at this state is. The kinematic viscosity of air at 20°C is V= 1. Calculating a new, corrected period in air from the experimental data in Fig. Dynamic Viscosity µ, kg / m · s. The kinematic viscosity of air at 15℃ is 1. Ammonia - Dynamic and Kinematic Viscosity vs. Also, make an estimate from ( c ) Fig. Its Correct answer is option 'D'. Example: 1. calculate orbital velocity and period of revolution of an altitude 200km radius =6400km mass of earth =6*10^26 Q. 81 0. The Kinematic Viscosity Of Air (In M²/S) At This State Is Select One: 0. 189: 0. Contact. Metric unit. 6 × 10 ∴ C. The kinematic viscosity is a measure of how rapidly momentum di↵uses into a flow. 9982 21 0. 83×10 -5 m 2 /s (e) 0 . 6 0. ) The kinematic viscosity of the same blends of camelina FAME and fossil kerosene cut K1 were measured at 40°C and 100°C, and extrapolated to −20°C according to the literature [41]. Tabulated values of ethane viscosity and viscosity units conversion Kinematic viscosity of air as alternative calibration gas media was evaluated at various pressure which suitable with gas CNG operation. 7: Kinematic viscosity is the ratio of absolute (or dynamic) viscosity to density. 000018 N•s/m² How to calculate the viscosity of air? First, determine the temperature. 2 K Fundamental Proper TABLE 1. Find viscosity tables and charts for water at multiple temperatures (viscosity and density values with their source). 137 kg/m³) and 101. (Total: 25 pts. C) 0: 100: 250: 500: (20 deg C) dynamic viscosity = 0,001 Pa. 83 x 10 kg/m-s. Re x = xv 1 = (3 ft) 20 ft s 0:1505 2 cm s 1Zin 2:54 cm 2 1 ft 12Zin 2 ˇ 4 105 Because the local Reynolds number is much greater than 1, the formula for the drag force is expected to be very accurate. Water at 20 °C has a kinematic viscosity of about 1 cSt. Can you explain this answer? in English & in Hindi are available as part of our courses for Mechanical Engineering. 9321 0. 07 E 52. Its kinematic viscosity at 70°C will be varying approximately[1999]a)2. 83×10−5 m2/s. Financial Accounting; Cost Management; Managerial Accounting; Advanced Accounting; Auditing; Air at 20⁰C and with 1 bar pressure is flowing over a flat plate at velocity of 2. The kinematic viscosity of air at a temperature and pressure of 25°C and 100 kPa is around 1. Determine the drag force exerted on a 163-m-long section of the wire during a windy day when the air is at 1 atm and 15°C and the wind is blowing across the transmission line at 50 km/h. 900m. The kinematic viscosity of air at this state is 0. For that reason, we created this calculator. 1–35 MPa Cite as: Journal of Physical and 2009 Joseph Kestin, H. 6 × 10 −3 Pa s at 37 °C, and that of air at room temperature (18 °C) is only 1. 00m. 34 1. 470 10-5 m2/s where: ν is the kinematic viscosity, ν = μ / ρ. Attention Mechanical Engineering Students! Question: The dynamic viscosity of air at 20°C and 200 kPa is 1. 6$. Markus Golbs Hamm AG. If the specific gravity at 20°C is 0. 77 × 10-5 m2 /s (c) 1. Determine the velocity with which air must flow over flat plate along 1. Compare with the accepted value of $\mu \approx 3. 132: 275: 1. 2-146 The dynamic viscosity of air at 20°C and 200 kPa is 1. Moreover, the dynamic viscosity of air remains same at constant temperature. 21: Air - Dynamic and Kinematic Viscosity Online calculator, figures and tables with dynamic (absolute) and kinematic viscosity for air at temperatures ranging -100 to 1600 The kinematic viscosity of water at 20 °C is about 1 cSt. 8663 50 57. 53 E 5 3. Do you agree? A million newtons is a lot, so this sounds like an awfully high flow rate. This must be calculated from the known viscosity and density of air and subtracted from the measured damping and period in air, since this drag vanishes when the cylinder is immersed in water. 51×10−5 m2/s. It is Consider a flat plate positioned inside a wind tunnel, and air at 1 atm and 20°C is flowing with a free stream velocity of 45 m/s. What is the kinematic viscosity of air at 20 degrees Celsius? What is the value of the kinematic viscosity of air at 300 K in m2 S? Temperature (K) Specific Heat Kinematic Viscosity1) – ν – (10-5 m2/s) – cp – (kJ/kgK) 250: 1. 5 Answer of The dynamic viscosity of air at 20°C and 200 kPa is 1. Estimate thedistance from the entrance where the hydrodynamic boundary layers of the two plates meet andverify if at that distance the flow is characterized by a laminar or turbulent regime. 38 Ns/m 2 and a specific gravity of 0. The kinematic viscosity of air at this state is (a) 0. 20°C. 6 × 10-5 °C is 1. 81: Methane: CH4: 0. Compute the absolute viscosity in lb-sec/ft². The kinematic viscosity is the dynamic viscosity divided by the density of the fluid. Determine the velocity gradient at the surface. 13 1. 29 E 5 2. Liquids - Latent Heat of Evaporation Latent heat of vaporization for fluids like alcohol, ether, nitrogen, water and more. 0182 mPa⋅s, thermal conductivity of 0. 000000045 The kinematic viscosity of air at a temperature and pressure of 25°C and 100 kPa is around 1. 998, compute the kinematic viscosity in ft²/sec. the temperature range 20–150 °C and the pressure range 0. 306 cP at 10°C (1 cP = mPa⋅s), it can vary enormously with temperature. You might witness dynamic viscosity denoted in 'centipoise' (cP), where 1 cP equals 0. If you need to learn more about the difference between Air at 25°C and 1 atm is flowing over a long flat plate with a velocity of 13 m/s. 83 X 10-5 kg/m•s. 3 a. Estimate/calculate the local, gas-side mass transfer coefficient for CO2 transport at 20°C in the tower if it is packed with 12-inch Raschig rings (ceramic) and the following apply: the superficial gas (air) velocity is 0. 0 m/s at the test section inlet, by how much will the centerline air speed accelerate by the end of the test section? The kinematic viscosity of air at 20°C is v 1. 25 1. 09 1. 4 0. which delays the mixing of air and fuel in the combustion chamber (Dharma et al. Part (b) Ethylene - Dynamic and Kinematic Viscosity vs. 1 MPa), and (c) pressure (at 20 °C and 3 Kinematic viscosity of seawater x 107 P0 (~ 1 atm or 0. 269 kg/m3 and v = 1. 77×10 -5 m 2 /s (c) 1 . 95 cm, but because of boundary layer displacement effects, the flow outside the boundary layer "sees" a plate that has larger apparent thickness. The density of the air can be estimated with the Ideal Gas Law ρ = p / (R T) There are 2 steps to solve this one. Here’s the best way to solve it. 1–35 MPa Question: Find the kinematic and dynamic viscosities of air and water at a temperature of 40 degree C (104 degree F) and an absolute pressure of 170 kPa (25 psia). Hello, %PDF-1. 52 m and width W = 2 m. There are 3 steps to solve this one. There is not a linear relationship, so you can't simply extrapolate the viscosity at different temperatures without additional information or tables. 204 kg/m2; kinematic viscosity is 1. Engine Oil SAE 15W-40 - kinematic viscosity and density over temperature SAE 10W-40. 000000010 0. 2. G. Question: What is the ratio of dynamic viscosity of air to that of water at standard atmospheric pressure and a temperature of 20°C? What is the ratio of kinematic viscosity of air to that of water for the same conditions? 5. Hydrogen - Density and Specific If the specific weight of a liquid at o degree Cis 9810 N/m and its kinematic viscosity is 1. 77×10 -5 m 2 Air - Dynamic and Kinematic Viscosity Online calculator, figures and tables with dynamic (absolute) and kinematic viscosity for air at temperatures ranging -100 to 1600°C (-150 to 2900°F) and at pressures ranging 1 to 10 000 bara (14. New Member . 98 E 5 3. 02437: 1025: 4. 7 0 0 m and a span of 1 4. Dynamic viscosity of seawater x 103, kg/m s P = P0 ( 1 atm for t <=100°C, Seawater vapor pressure for t > 100 °C) 2 The kinematic viscosity of air at a temperature and pressure of 25°C and 100 kPa is around 1. Dynamic viscosity of air at 170kpa and 40 C is = 19. 0038: Download scientific diagram | Kinematic viscosity values at 40 °C of acetone (ACE)/ sunflower oil (SO) and ACE/ castor oil (CO) double blends with different proportions of acetone; cSt Example value Air (0 deg C) dynamic viscosity = 17 X 10-6 Pa. 47×10 -5 m 2 /s (d) 1 . The apparent thickness of the plate is _____ cm. 5 cm wide and at 60⁰C, calculate the value of boundary layer thickness, average fraction coefficient, shear stress due to friction, local convective heat transfer coefficient, average heat transfer coefficient, rate of heat transfer by convection and total drag on the plate. 0 m/s at the test section inlet, The kinematic viscosity of air at 20oC is ? = 1. 01171 4. Density =1. Solution. 1000 points value Required information What is the minimum length of the plate necessary for the Reynolds number to reach 2 x107? Assume air at 20°C and atmospheric pressure on a smooth flat plate with a speed free current of 25 m/s (kinematic viscosity of 1. 01 0. 047934: 21: 0. operating at . It is estimated that the accuracy of the tabulated values is ±0. Question: The dynamic viscosity of air at 20°C and 200 kPa is 1. 47×10−5 m2/s (b) 0. P6. Engineering; Civil Engineering; Civil Engineering questions and answers; 4. 9565 0. Temperature and Pressure The plate thickness is h-0. 2 × Solution for The dynamic viscosity of air at 20°C and 200 kPa is 1. A c-cordingly, The formulas for calculating dynamic and kinematic viscosity are: * Dynamic viscosity: μ = ρ × T^3/2 * Kinematic viscosity: ν = μ / ρ At standard conditions (20°C, 1 atm), the kinematic viscosity of air is approximately 15. Additionally, dynamic viscosity can be expressed in terms of the fluid's mass density (\( \rho \)) and kinematic viscosity Question: A packed column (tower) is to be used to remove CO2 from a gas flowing in the column alongside a liquid. 51 × 10^-5 m^2/s. If we look at air now, we see that at 15 °C, the viscosity of air is $ \mu_{air}=1. If the pressure is decreased to 20 kPa, but the temperature remains the same, the kinematic viscosity of air is nearest (Hint: assume air as an ideal gas. 199217 kg/m 3 at 40 °C = 1. a. 86 E-5 2. 11 4 4 bronze badges $\endgroup$ Diffusion coefficients (D 12) for gases in large excess of air at temperatures ranging 0 - 400 °C. 9775 0. temperature of 20C and a pressure of 1 atm. 562x10 m/s. 289: 0. Kinematic viscosity has the dimensions of a di↵usion coecient. The dynamic viscosity of air at 20 ° C and 200 kPa is 1. 4 cSt at 40 C and 11. 83×10 -5 kg/m ⋅ s . Tasks. A fluid at 20°C flows at 0. 0001 m 2 /s) Variation of viscosity with temperature: Dynamic viscosity η increases for gases as temperature rises. [°C] Dyn. Engine Oil. Plate The dynamic viscosity of air at 20°C and 200 kPa is 1. A flat plate 1m wide and 1. Can you explain this answer?, a detailed solution for Kinematic viscosity of air at 20°C is given to be 1. The air is at 20 °C. Can you explain this answer? Kinematic viscosity of air at 20°C is given to be 1. 65*10-5 Kg/M S. 27. The plate is 2 m long and 2 m wide. The kinematic viscosity of air in this state is. 158 3 1026 8. 287[kJ / kg - K] A laminar flow wind tunnel has a cylindrical test section that is 30 cm in diameter and 80 cm in length. 1 Physical Properties of Air at Standard. Join Date: Nov 2009. 5 KB) Viscosity (SI). 525×10−5 m2/s (c) 1. All properties are under 1 atm (1. nu = mu / r Re = V * L / nu The units of nu are length^2/sec. 2 m. 0°C. The density and kinematic viscosity of air at 1 atm and 25°C are p = 1. Temperature and Pressure Ethylene - Dynamic and Kinematic Viscosity vs. For a dynamic viscosity of 0. 0031: 1. 08 x 104 m2/s) Air (kinematic viscosity, v= 1. Calculate the apparent thickness of the plate (include both sides) at downstream distance x = 10 cm. 111770 kg/m 3. The viscosity on this page is the dynamic (absolute) viscosity. in the UBBELOHDEviscometer. (AU2013) Given: Fluid temperature T inf = 20 o C . 83 × 10⁻⁵ kg/m⋅s. icoFoam >> density >> kinematic viscosity for air 20°C #1: mgolbs. 7246 2 100 2. b) 5. 1 MPa), (b) temperature (at 32. The dynamic viscosity of air at 20° C and 200 kPa is 1. Posts: 26 Rep Power: 17. The properties of air at 110oC are: density = 1 kg/m3, kinematic viscosity = 21 × 10-6m2/s, thermal conductivity = 0. Properties of saturated liquid Mercury - Hg - density, specific heat capacity, kinematic viscosity, thermal conductivity and Prandtl number. 6959 psi) unless specified otherwise. Tsai, Y. 155 C/so 3. Glycerin:-20°C. Centipoise is frequently used because water, a common reference fluid, has a dynamic viscosity of approximately 1 cP at 20°C. b. 96 17. 2 × 10-5m2/sb)1. Gas constant for air: 287 Nm/(kg K) 1. , (water at 20°C 1 mPas). Question: d) Air at 20 °C (Kinematic Viscosity, 9 = 1. 0034 0. Other units for kinematic viscosity Question: Air at 25°C and 1 atm is flowing over a long flat plate with a velocity of 8 m/s. 83′10−5 kg/m×s(R=0. View a sample solution. 01582 Tabulated values of the dynamic and kinematic viscosity of aqueous sodium chloride solutions are given. 5 m long is to be maintained at 90°C in air with a free stream temperature of 10°C. All samples were filled at +20°C. 03 39 Air at 20°C is flowing along a heated plate at 200°C at a velocity of 4 m/s. 6×10 ° 1. Use the following material properties of air: kinematic viscosity 15. s = 0,017 cPoise. Dynamic viscosity measured was then converted into kinematic viscosity (υ, Eq. 90 0. 104 stokes. 11×10-6m2s2. However, most measurements are still made in centistokes, e. Find step-by-step Engineering solutions and your answer to the following textbook question: Knowing the value of $\mu$ for air at $20 \degree C$ from Table $1. 2 kg/m3). 6 × 10–5 m2/s. 12. 1. Calculate the lift force generated by a NACA1408 airfoil with a chord of 1 meter and a . 10 0. Air - Dynamic and Kinematic Viscosity Online calculator, figures and tables with dynamic (absolute) and kinematic viscosity for air at temperatures ranging -100 to 1600°C (-150 to 2900°F) and at pressures ranging 1 to 10 000 bara (14. 156 x105 m2/s flows parallel to a smooth, thin flat plate at 4. Viscosity [mm²/s] Density [g/cm³ Steam at boiling point properties - density, specific heat, viscosity If the dynamic viscosity of water at 20°C is 1 x 10-3N-s/m², what is the kinematic viscosity in the English units? Similitude Water flows through a 5 inch diameter pipe at 10 ft/s. Determine whether the flow is laminar or turbulent if the fluid is: - i) ii) iii) iv) Hydrogen (kinematic viscosity, v= 1. 2 x 10-5m2/sb)1. At 25 ℃, the kinematic viscosity of Kinematic viscosity of air at 20°C is given to be 1. 2 6 105 b) 1. s (x 10’) Air (dry) 26 28. 287 kJ/kg−K). Determine the distance from the leading edge of the plate where the flow becomes turbulent and the thickness of the boundary layer at a location when Xct. 7×10-6m2s, Prandtl number The dynamic viscosity of air at 20°C and 200 kPa is 1. Rent/Buy; Read; Return; Sell; Study. Ezzat Khalifa, and Robert J. At a uniform air speed of 2. Kinematic find it's air at 20°c viscosity q Kinematic viscosity at 70°c. 2 m×0. 205 kg/m3. Air - Humidity Ratio The mass of water vapor present in moist air - to the mass of dry air. 0 0 m operating at 5 0 m s and an angle of attack of 8 degrees in air at a Question: The dynamic viscosity of air at 20∘C and 200kPa is 1. Equation: ν = η / ρ. 516 × 10^(-5) m^2/s. 6 × 10-5m2/s. 01325×10 5 Pa; 760 mmHg; 14. 134. 0 32 5 41 10 50 15 59 -20 68 25 77 30 86 40 104 50 Show transcribed image text Here’s the best way to solve it. 001 Pa. 3 kPa pressure. com. s] Kin. Methanol - Dynamic and Kinematic Viscosity vs. The air is at 20°C. Kinematic viscosity of air at 20°C is given to be 1. S unit of kinematic viscosity is cm 2 /s or, Stoke. The heating profile for the temperature controller was set up as: heat from 23°C until the smoke point of each oil (200°C, except olive oil 180°C) in increments of 20°C and holding at each temperature for 5 min. The density and kinematic viscosity of air at 1 atm and 25°C are p= 1. The drag force was 0. 287[kJ / k * g - K] (i) 0. In cgs units the unit is called the centistoke. (Round the final answer to the nearest whole. View this answer View this answer View this answer done loading. 07 E 5 2. 946% of the air volume. The viscosity of air at 20° C is 0. 331 μ ≈ 1. Temperature and Pressure Online calculator, figures and tables showing dynamic and kinematic viscosity of ethylene, C 2 H 4, also called ethene or acetene, at varying temperature and pressure - Imperial and SI Units. To start, locate the dynamic viscosity of air at 40°C and an absolute pressure of 170 kPa in the property tables for air. Temperature and Pressure Kinematic viscosity measured at 40 • C with the use of four different devices, (moisture, air dust, air, and other gases) at 20 C and mixed before the measurement. Given Data - Kinematic viscosity of air at 20°C: ν = 1. Financial support was provided by grants from the Department of Zoology, Wisconsin Alumni Research Foundation, ERDA (Contract EY-76-5-02-2270), and NSF (Grant Nos. xls (105 KB) This material was prepared as an account of work sponsored by an agency of the United States Government. Density Heat c p Conductivity Diffusivity Viscosity Viscosity Number T, 8C r, kg/m3 J/kg·K k, W/m·K a, m2/s m, kg/m·s n, m2/s Pr 2 150 2. Other units for kinematic viscosity The bath temperature is to be maintained at 40 ± 0. 06 1. The data shown yellow can be changes to recallate the selected variables. Properties of fluids Air: at 25°C: Kinematic viscosity: v= 15. For instance, air at 20 C and 1 atmosphere, It takes about 20 min at 38°C, 25 mm at 100°C and 30 miii at 135°C. : 2. Step 4 For example, the viscosity of water, μ water, is 10 −3 Pa s at 20 °C, while that of plasma is 1. With filling, cleaning and drying at -20°C, which requires a supply of Assume air at 20°C and atmospheric pressure on a smooth flat plate with a speed free current of 25 m/s (kinematic viscosity of 1. Here's a JavaScript program to calculate the coefficient of viscosity and the Reynolds number for different altitude, length, and speed. 0 p,Pa s be adopted as a standard [1, 3, 4]. Therefore, it's a quantity that represents the dynamic viscosity of a fluid per unit density and is expressed in m ² / s \rm Dynamic Viscosity Air @ 1 atm vs Temperature . temperature and frequency. Air - Dynamic and Kinematic Viscosity Online calculator, figures and tables with dynamic (absolute) and kinematic Density of hydrocarbons like alcohols and acids as function of carbon number at 20°C / 68°. 4$, calculate its viscosity at $500\degree C$ by ( a ) the power law and ( b ) the Sutherland law. Step 2 of 4. Temperature and Pressure The air is at 20°C. 6: nitrogen: 0: 16. 83 × 10-5 m2 /s (e) 0. 20\\\\deg C. 1. (Boundary layer pinch-off) Air at 20 °C flows at 1 m/s between two parallel flat plates spaced 5 cm apart. For example, the viscosity of water, μ water, is 10 −3 Pa s at 20 °C, while that of plasma is 1. Methane - Dynamic and Kinematic Viscosity vs. Related Resources: The properties listed are density, viscosity specific heat capacity, thermal conductivity and Prandtl number. 770 X 10-5 m/s 1. 612: 0. The density and kinematic viscosity of air at 1 atm and 15 C are p 1. 1, Q. From Table 1. Air at 1 atm and 20°C (density of air is 1. 1 0. 2 × Viscosity of gas increases with increasing temperature. 12 cSt at 100 C. ) The kinematic viscosity of air at this state is (a) 0 . 013 3 1026 0. MrBellamy MrBellamy. Please provide SI units. 14 E 52. Calculate the lift force generated by a NACA 1 4 0 8 airfoil with a chord of 1. There are 2 steps to solve this one. Viscosity Converting Chart Convert between viscosity units like Centiposes, milliPascal, CentiStokes and SSU. Concept: Variation of viscosity with temperature: On this page, you can find the dynamic (absolute) and kinematic viscosity of air at different temperature values in both SI (cP) (cSt) and US customary (lbf·s/ft 2) (ft/s 2) units, taken at 1 atmospheric (atm) pressure. Welcome to the water viscosity calculator, a tool that will let you calculate water viscosity (kinematic or dynamic viscosity) within the 0-370°C temperature range. 437: 0. 1–35 MPa and is the concentration range 0–6 molal. Jet A1 JF1411 and reference standard Jet N2B were tested as tables scan with variable steps from -20°C to -56°C. 998 22 0. 83 × 10 -5 kg/m·s. Users who prefer Standard or other unit systems rather than SI units, please click the amount (number) of the specific material property for unit conversion. Calculate the lift force generated by a NACA 1408 airfoil with a chord of . Air at 20 o C flows over a flat plate at 60 o C with a free stream velocity of 6 m/s. 000000045 Obtain the properties of air at a temperature of from Table B. Air 1 m/s- 20°C According to the above-mentioned equation, the kinematic viscosity of air is highly dependent on temperature. 51 x 10^-5 m^2/s. 47 × 10-5 m2 /s (d) 1. 0 W/m^2 K. 6 , how to find VI? Kinematic viscosity: 99. Ethylene - Dynamic and Kinematic Viscosity vs. 48 x 10-5 m 2 /s or 14. 9: hydrogen: 0: 8. The kinematic viscosity of air at this state is (a) 0 . 225 kg/m3 and v 1. 95 0. The values of μ, cp and k are acknowledged to change with temperature consequently the GATE online practise tests question & answers in Fluid Mechanics, Kinematic viscosity of air at 20°C is given to be 1. the viscosity of water at 20° C and a pressure of 0. The dynamic viscosity of air at 20°C and 200 kPa is 1. measures the kinematic viscosity of lubricants [Mott, p. Books. 385 x 10^-5 kg/m s So, the dynamic viscosity of oxygen at 20°C and a pressure of 150 kPa (abs) is The momentum diffusivity is also known as kinematic viscosity. 71 . 287[kJ / kg - K] Find the dynamic and kinematic viscosity of air at 20 degrees celsius and seawater at 10 degrees celsius under atmospheric pressure. Air properties: Kinematic viscosity (u )=15. Tabulated values of the dynamic and kinematic viscosity of aqueous sodium chloride solutions are given. One way is to measure a fluid’s resistance to Find step-by-step Engineering solutions and your answer to the following textbook question: The viscosity of water at 20°C (68°F) is 1. ) You might witness dynamic viscosity denoted in 'centipoise' (cP), where 1 cP equals 0. The portal brings together and enhances the 1= 20 ft=s. If the surface temperature of the plate is 400K, the average heat transfer coefficient is most nearly a) 2. 7 x 106 m3/s, Prandtl number Pr = 0. 83 × 10−5 kg/m⋅s. Your solution’s ready to go! Our expert help has broken down your problem into an easy-to-learn solution you can count on. 2. Atmospheric air at 20°C and free stream velocity of 3 m/s flows over a flat plate 0. 3 mm and basis weight of 30 gsm, a pressure drop of the air across the web of 2. Calculate the kinematic viscosity of air at this state. Engineering; Chemical Engineering; Chemical Engineering questions and answers; The dynamic viscosity of air at 20 C and 200 kPa is 1. 5 m/s parallel to a flat plate as shown in the figure. Density of hydrocarbons like alcohols and acids as function of carbon number at 20°C / 68°. SAE 10W30. The correlating equations from which the tables were generated are given. , Viscosity, v, 20°C (68°F) B Gas Viscosity Ratio of Molecular Dynamic, p, Kinematic, Y, Specific Tcrit, pcrit, Weight Density, kg/m3 kg/m. 9344 0. 9978 23 0. 17 1. The viscosity of air depends mostly on the temperature. and a span of . The viscosity of oligomeric resins used in the 100% liquid formulations may vary in a larger range of 0. Dynamic viscosities of some fluids at 1 atm and 20°C (unless otherwise stated) Fluid. 2 x 10-5m2/sd)2. The air speed increases by 149 %. 20 1. s = 0. 00 0. Note: 1. 184 kg/m and v= 1. 967 List of Figures 1. 00269 0. Air at 20∘C flows over both sides of a surface measuring 0. 7, and the thermal conductivity is 30*10-3Wm*K. Another example might be Here you can find the meaning of Kinematic viscosity of air at 20°C is given to be 1. Air at 20 °C flows at V = 10 m/s over a flat plate of length L= 1. Regions of experimental data on the viscosity of The viscosity of air can vary depending on many factors including temperature. 000000007 0. 20 cSt. Show transcribed image text. What is the minimum length of the platenecessary for the Reynolds number to reach 2 ×107? When the critical Reynolds number is 5 × 105, determine thevalue of Reynolds number for the type of flow regime that the airflow will experience at 0. 31 178. 8 13 o 6 20 N-s/m r mc kp = = = ´-. 6×10². 225 Kg/m 3: 0. 5 m wide. Step 1. (1 stoke = 0. The average kinematic viscosity of the air is 20. 057 105. 104 x 10^-4) * 1. . 83 × 10-5 kg/m·s. 525 × 10−5 m2/s (b) The kinematic viscosity of air at 20\\\\deg C is. Question Oil droplets having a diameter of 20 mm are to be settled from air at 311K (dynamic viscosity of air = 1. (viscosity of air at 20 and 25 °C for 1 atm) . 2 m from the leadingedge. Test duration: 1h 40 min. 8 × 10^{-5}~Pa. 42: helium, gas: 0: 18. Numerous other related values such as the kinematic coefficient of air viscosity, gen molecules up to O 2 20. 33 g/kg and 0. in the flow direction. k is thermal conductivity, (SI units: W/m·K) cp is specific heat, (SI units: J/kg·K) ρ is density, (SI units: kg/m3). Your comments will be displayed only after manual approval. 97 10-6 m 2 /s) . 3 %東京 ReportLab Generated PDF document http://www. 562x10-5 m2/s. The calculator can either be used in Kinematic viscosity ν ν ν is the dynamic viscosity divided by density ν = μ / ρ ν = \mu/\rho ν = μ / ρ. 866 983 0. 03 W/m-K, Prandtl number (Pr) = 0. 830 X 105 Online calculator, figures and tables with dynamic (absolute) and kinematic viscosity for air at temperatures ranging -100 to 1600°C (-150 to 2900°F) and at pressures ranging 1 to 10 000 bara (14. Its kinematic viscosity at 70°C will be varying approximately Question: Air at 20°C flows at 1ms between two parallel flat plates spaced 5cm apart. 83 x 10-kg/m-s. Viscosity (English). Absolute or dynamic viscosity is used to calculate Reynold's Number to determine if a fluid flow is laminar, transient or turbulent. Its kinematic viscosity at 70°C will be approximately. c) 7 The air is at 20°C. Also determine the friction coefficient if the free stream velocity has a value of 40 m/s. The most frequently used systems of US customary, or Imperial, units are the British Gravitational (25 °C and pressure of 1 bar), the dynamic viscosity of air is 18. 83 * 10-5 kg/ms. 8 L/s through a 100 mm diameter of pipe. 0016 1. 02 x 10-5m2/sCorrect answer is option 'D'. 3 kPa: 2116. It is adjudged that this standard value has an accuracy of ±0. 6 m/s . Take home (20) II. 5 W/m^2 K. 948 PROPERTY TABLES AND CHARTS TABLE A–9 Properties of air at 1 atm pressure Specific Thermal Thermal Dynamic Kinematic Prandtl Temp. Find the kinematic and dynamic viscosity of air and water at 40 degree C and an absolute pressure of 170 kpa. 5 - 145000 psia) - SI and Imperial Units. The properties r, n, and a at a pressure P (in atm) other than 1 atm are deter-mined by multiplying the values For instance, if the input temperature (x) is 20°C and the pressure (y) is 1 atm, the kinematic viscosity of air would be calculated as (output example). 076kg/m , 1008J/kgK, 0. Determine the kinematic viscosity of air at this state. 562 x 10 m/s. Although water viscosity in cp is 1. Step 3 of 4. The SI unit of the kinematic viscosity is m 2 /s. 75 slugs/ft3 0. Note: Pay attention to the units for viscosity. 17 E 5 2. 000000044 0. 000182 O 0. P. Kinematic Viscosity - Online Converter Convert between kinematic viscosity units like centistokes, poise, lentor and more. 5 - 145000 psia) - SI and Imperial Kinematic viscosity of air at 20°C is given to be 1. 75 m/s. 97 0. 516 *10-5 m²/s) at V = 9. 91 flows through a 25 mm diameter pipe with a velocity of 2. Temperature and Pressure Preface to the Third Edition. 40 1. 00179 O 0. There is a uniform air speed of 2 m/s at the test section inlet. 05 to 100 Pas, 20 287. Pressure, $P$ 101. Compare the two Laminar and Turbulent Boundary Layer profiles across the length of the plate. 51×10-5 m 2 /s or 15. Dynamic Viscosity of Water @ 1 atm vs Temperature . Kinematic viscosity has a value of 15. SI unit of kinematic viscosity: [ν] = m²/s. 184 kg/m3 and v= 1. Attachments. So one can see that comparing those fluids for the conditions I provided that : 2021 at 20:18. 10. 23 326. The lift force generated is Ibf. 400 200 100 60 40 20 10 Smooth cylinder 0. 2 0. Its kinematic viscosity a t 70°C will be vary approximately The relationship between kinematic viscosity (ν), dynamic viscosity (μ), and density (ρ) is given by: ν = μ / ρ We can rearrange this equation to solve for dynamic viscosity: μ = ν * ρ Now, plug in the values for kinematic viscosity and density: μ = (0. Yan, in Applications of Nonwovens in Technical Textiles, 2010 Using air viscosity (μ) of 185 × 10- 5 N s/m 2 at 25 °C, an entrance velocity (v 0) of 5. The kinematic viscosity of air at 20C is 15. 8 mmH 2 O, and a PP having The Reynolds number is an important dimensionless quantity used to predict whether a flow is laminar or turbulent, and is defined as the ratio of inertial to viscous forces in a fluid. 00247 0. 7, Cp of air = 1. 380 × 10-5 m2 /s Write an essay on. 9544 0. 17. 8 cSt. 525 X 10. and a pressure of 1 atm. 83×10−5 kg/ms. 201* 10-6 View the full answer In essence, kinematic viscosity is a measure of the resistive flow of a fluid under the influence of gravity. Other units are: 1 St (Stoke) = 1 cm 2 /s = 10 −4 m 2 /s. der. 00257 0. 00109: 0. 45 m/s over a square flat plate 1m on each side. 02291: 1025: 4. Solution: For SAE 30W oil at 20°C Question: Air at 20°C with kinematic viscosity of 1. 0020 millipascal seconds air: 15: 17. Its kinematic viscosity at 70°C will be approximately - 52794492 The kinematic viscosity of air at 20°C is ν = 1. 00182 In the figure shown, compute the pressure difference between m and n when2. 26 J/Kg K) At 32°C And 191 KPa Abs Is 1. The thickness of the boundary layer is cm. 01cms, the kinematic Q2. C)-25: 0: 20: 50: 100: 200: Kinematic Fluid viscosity tables. 9795 0. 9x103 20 °C 100 °C 200 °C 300 °C 400 °C ; Name Formula 32 °F 68 °F 212 °F 392 °F 572 °F 752 °F ; Argon: Ar: 0. Estimate the distance from the entrance to the point at which the hydrodynamic (velocity) boundary layers meet. As the temperature increases, the kinematic viscosity of air increases. The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress . Property. 06×10−6 m2/s. Kinematic viscosity of air at 1 bar (1 10 5 Pa, N/m 2) and 40 o C is 16. 92*10-6m2s, the Prandtl number is 0. Kinematic viscosity is most relevant to constant density, incompressible flow. 10325 MPa) 3 4 Osmotic coefficient of seawater P0 Temperature, oC S = 120 g/kg 100 80 20 40 60. 1 %. 966 14. Determine the Reynolds number and the boundary layer thickness at the end of the plate if the plate length is: b) i) 3 m long i) 1 m long . s = 1 cPoise. 008 cp (centipoises). 000179 O 0. 516x 10-5 m2/s. TABLE C. 78 0. 6162. 525 X (R = 0. 7 lb f /ft 2: Density, $ρ$ 1. com % 'BasicFonts': class PDFDictionary 1 0 obj % The standard fonts dictionary /F1+0 367 0 R Solutions for Kinematic viscosity of air at 20°C is given to be 1. 164 kg/m3 and air kinematic viscosity, = 1. If it flows over a plate and has the following velocity profile as measured from the plate surface: V(y)=9y2+3y Consider air Viscosity - Absolute (Dynamic) vs. Air at 20°C flows at V = 8. The kinematic viscosity of air at 20°C is 15. Determine the Note: For ideal gases, the properties cp, k, m, and Pr are independent of pressure. The plate is 4 m long and 1. é ùë ûAns: 0. The SI unit is m 2 /s (see Viscosity). 6x 10-5m2/s. 49. 007: 0. 97 cSt (16. 0038: The kinematic viscosity [m 2 /s] is the ratio between the dynamic viscosity [Pa. 5%. Online calculator, figures and tables with dynamic (absolute) and kinematic viscosity for air at temperatures ranging -100 to 1600°C (-150 to 2900°F) and at pressures ranging 1 to 10 000 bara (14. Solubility of oxygen in equilibration with air in fresh water and seawater (salt water Seawater - Attenuation of Sound Attenuation of sound in seawater vs. 5 × 10^{-5}~m^2 /s$. 025596 W/m⋅K and specific heat of 1006 J/kg⋅K, Final Answer: The ratio of the dynamic viscosity of air to that of water at standard pressure and a temperature of 20 degrees Celsius is option (d) 55. All the above blends showed small nonlinearities with the volume fraction of DFAME and camelina FAME, and they all also met the ASTM D1655 specification (<8 mm 2 /s). 801 m/s. In the case of viscosity data at low pressures and at other temperatures the The plate thickness is 0. Viscosity [mPa. 715. It takes about 20 min at 38°C, 25 mm at 100°C and 30 miii at 135°C. 50(m)/(s) and an angle of attack of 8 degrees in air at a temperature of . 03 E -5 2. Relationship between dynamic and kinematic viscosity v . 20 1. Kinematic viscosity has dimensions of length2/time; dynamic viscosity has dimen-sions of density times this or mass/length·time. The long of the train is 15 m. 00237 The kinematic viscosity of the same blends of camelina FAME and fossil kerosene cut K1 were measured at 40°C and 100°C, and extrapolated to −20°C according to the literature [41]. Kinematic Vicosity is a fluid's resistance to flow The kinematic viscosity of air at 20°C is given as 1. 19 Determine the change in the kinematic viscosity of air that is heated from 10°C to 70°C. Temperature and Pressure Online calculator, figures and tables showing dynamic and kinematic viscosity of ethanol, C 2 H 5 OH, at varying temperature and pressure - Imperial and SI Units. Dynamic viscosity of Online calculator, figures and tables with dynamic (absolute) and kinematic viscosity for air at temperatures ranging -100 to 1600°C (-150 to 2900°F) and at pressures ranging 1 to 10 000 bara (14. The known kinematic viscosity allows us to determine how air flows around the plate and predict the transition from laminar to turbulent flow. 382x 10-5 m2/s and the density of hail is given to be 910 kg/m3 drag coefficient for cross-flow over a smooth circular cylinder and a smooth sphere is given below. 1 An engineer claims that flow of SAE 30W oil, at 20°C, through a 5-cm-diameter smooth pipe at 1 million N/h, is laminar. 3m a) velocity boundary layer thickness, b) local and avg friction coefficient, c) local shear stress due to friction, d) local and total convective heat transfer coefficient e) total heat transfer rate from the plate to air over 20: 0. 79*106 m/s, what is its dyname viscosity? O 0. 167: 0. Table of Fluid viscosities Download scientific diagram | Dynamic viscosity of saline water as a function of (a) salinity (at 20 °C and 0. The dynamic viscosity of air at 20 ° C and 200 kPa is 1 . 1-2 on page 14, the kinematic viscosity of air at 20° C is = 0:1505 cm2=s. Show transcribed image text There are 2 steps to solve this one. 5x10-5 m2/s and density 1. SAE 10W. ) Show transcribed image text. Show transcribed image text Here’s the best way to solve it. 3. 6 × 10⁻⁵ m²/s; Effect of Temperature on Kinematic Viscosity Answer to TABLE C. 000016478 kg/m. 3 Viscosities of Water and Air Air Water Temperature Viscosity (u) (°C) (°F) 88888888-5. 3 Mechanical Properties of Air at Standard Atmospheric Pressure Kinematic Viscosity m2/s Temperat —20 —10 10 20 30 40 50 60 70 80 90 100 120 160 180 200 00 20 60 80 1000 120 150 200 300 400 Density kg/m3 1. $1. Skip to main content. Measure or calculate the temperature of the air in Kelvin. At 15 °C, the The kinematic viscosity of air at 20 degrees Celsius and 1 atm (101,325 Pa, sea level) pressure is approximately 1. Explanation: Dynamic viscosity is a measure of a fluid's resistance to flow. Temperature and Pressure Find step-by-step Engineering solutions and the answer to the textbook question The kinematic viscosity of oxygen at $20^{\circ} \mathrm{C}$ and a pressure of 150 kPa (abs) is 0. 77×10−5 m2/s (d) 1. Temp. 5 μPa·s, roughly 50 times smaller than the viscosity of water at the same temperature. 075 N. Temperature and Pressure Ethanol - Dynamic and Kinematic Viscosity vs. 97 E 5. Calculate the apparent thickness of the plate (include both sides) at downstream distance x= 10 cm. 6478×10 -5 kg/m. Determine the thickness of the boundary layer at the location of the plate where the flow becomes turbulent. The gas constant R -0. Comparison of the present correlation with oth er correlation and selected experimental data (thermal conductivity of air at room tempera-ture and for 1 atm) . Question: Problem 3: Air at a temperature of 20∘C and pressure of 1 atm has a kinematic viscosity of 1. 3m a) velocity boundary layer thickness, b) local and avg friction coefficient, c) local shear stress due to friction, d) local and total convective heat transfer coefficient e) total heat transfer rate from the plate to air over Kinematic viscosity (ν) designates the quotient of the dynamic viscosity of the fluid handled and its density. 51 x 10-5 m-/s) Gasoline (kinematic viscosity, v=4. reportlab. The viscosity of water decreases smoothly from the freezing point while the density remains essentially constant except for the small maximum in density near 4°C . The front of the plate is well rounded, and the plate is 40 cm long. s. 1 Physical Properties of Air at Standard Atmospheric Pressure (SI Units)* Dynamic viscosity, Kinematic viscosity, Specific heat ratio 5 1. By assuming the outer wall of the train is flat, air density, = 1. 83 * 10 ^ - 5 / kg / m * s The kinematic viscosity of air at this state is: R = 0. Chemical symbol: Temperature (Deg. Other common kinematic viscosity systems such as Saybolt Universal Seconds (SUS) and the SAE grading system can be related to the measurement of the viscosity in cSt at either 40°C or 100°C. The kinematic viscosity ν (ν = "nu") is the dynamic viscosity of the medium η divided by its density ρ. 827 × 10 −5 Pa s. r = =c p Take the following properties of air: 1. Measure to the nearest 0. span of 15 meters operating at 50m/s and an angle of attack of 8 degrees in air at a . For further definitions, go to Absolute (dynamic) and kinematic viscosity . Standard sea-level atmospheric conditions: pressure = 101,325 N/m”, temperature = 298 K. the working pressure in accordance with the results of the calculated pressure while the temperature was fixed at 20 °C or 293 K. This point will be The following table defines the average Kinematic Viscosity for selected liquid fluids. ρ is density, (SI units: kg/m3). A Newtonian fluid with a dynamic or absolute viscosity of 0. Viscosity - Absolute (Dynamic) vs. Remove the stopper in the tube N and L respectively and allow the sample to flow by gravity. A container, held at constant temperature, is filled with 60 ml of fluid. Liquid. Accounting. Consider a flat plate positioned inside a wind tunnel, and air at 1 atm and 20°C is flowing with a free stream velocity of 45 m/s. 0001 m 2 /s) Variation of viscosity with temperature: Units in gas viscosity calculation o C=degrees Celsius, K=Kelvin, o F=degrees Fahrenheit, o R=degrees Rankine, lb-s/ft 2 =pound-second per square foot, slug/ft-s=slug per foot per second, N-s/m 2 =Newton-second per square meter, kg/m-s=kilogram per meter per second, SG=specific gravity. For gases like air, kinematic viscosity increases with temperature. xls (106. 74-19454 and 77-25786 to WPP). Kinematic Vicosity is a fluid's resistance to flow and can be valued as dynamic (absolute) or kinematic. s$ and its kinematic viscosity is $\nu_{air} = 1. The tables cover the temperature range 20–150 °C, the pressure range 0. Assume that the kinematic viscosity v (= u/p) of air at 20 Example value Air (0 deg C) dynamic viscosity = 17 X 10-6 Pa. 636 3 1026 3. The dynamic viscosity of air at sea level under the same temperature is Kinematic viscosity of air at 20°C is given to be 1. 3 cm/s, a PP web with a thickness of 0. 40°C. 249 x 10^-5. 20°C (66°F) Liquid Dynamic Kinematic Vapor Sound Density, Viscosity, p. 01 °C, as the kinematic viscosity of petroleum oils are traditionally measured at this temperature and viscosity standard oils calibrated at 40 °C are commonly available. 525 i m e s 1 0 Air - Dynamic and Kinematic Viscosity Online calculator, figures and tables with dynamic (absolute) and kinematic viscosity for air at temperatures ranging -100 to 1600°C (-150 to 2900°F) and at pressures ranging 1 to 10 000 bara (14. 06 x 10-7 m2/s) Engineering; Chemical Engineering; Chemical Engineering questions and answers; The dynamic viscosity of air at 20 C and 200 kPa is 1. 40]. g. Density of air at 20 °C = 1. Additionally, dynamic viscosity can be expressed in terms of the fluid's mass density (\( \rho \)) and kinematic viscosity The kinematic viscosity for air at 20°C is ν = 1. A laminar flow wind tunnel has a test section with a cross section of 41 cm × 41 cm and a length of 80 cm. 58\ \text{E}$ - $5\text{ Example - Calculate Reynolds Number. 6 x 10-5m2/sc)1. and Show the relationship between viscosity (vertical) and temperature (horizontal) of ISO VG 100 oil The dynamic viscosity coefficient divided by the density is called the kinematic viscosity and given the Greek symbol nu. Advertisement Advertisement New questions in Physics. 516 × 10-5 m2/s. μ is dynamic viscosity, (SI units: Pa s = N s/m2). Table of Fluid viscosities Kinematic Viscosity of Air Kinematic viscosity is a measure of a fluid's internal resistance to flow. 6 × 10-5m2/sc)1. hey , given viscosity of 1000 cSt at -20 deg C , and ASTM slope of 0. 1 seconds the time required for the leading edge of the meniscus to The influence of fiber and fabric properties on nonwoven performance. Density can be calculated from Question: 26) The dynamic viscosity of air at 20∘C and 200kPa is 1. 29 1. 3m wide maintained at uniform temp of 100 °C, calculate following @ x = 0. The viscosity of water at 20 °C is 1. Next, determine the constants. 001 Pa s and is is sometimes written mPa s. 0 m/s over a smooth plate of Length L = 1. 0. 287 kJ/kg. If the if the plate is 27. 525 * 10 ^ - 5 * m Air at 300K flows at 0. 50 m. It is given by the formula: μ = ρ * ν, where μ is the dynamic viscosity, ρ is the density of the fluid, and ν is the kinematic viscosity Take the density and kinematic viscosity of air at 1 atm and 5°C as ρ = 1. Measure the time t for the fluid to drain from a small For air at 20°C = 293 K and 7000 Pa, the density is ρ = p/RT = (7000)/[(287)(293)] = Answer to Solved The dynamic viscosity of air at 20 ° C and 200 kPa is | Chegg. 83 * 10 ^ - 5 * kg / m * s The kinematic viscosity of air at this state is : R = 0. Its kinematic viscosity at 70°C will be approximatelya)2. 002378 slug/ft 3: Temperature, $T$ 15 o C , 288. 4: Dynamic viscosity of air, Chapter 1, Problem 67P is solved. Thus water at 20 ºC has a kinematic viscosity ν = 1,002 · 10 −6 m 2 ∕s. 000000034 0. The kinematic viscosity in cSt at 40°C is the basis for the ISO 3448 kinematic viscosity grading system, making it the international standard. The air speed. 516x10 m/s) flows tangentially on both sides of a thin, smooth flat plate of width 3m and of length 1m in the direction of the flow. The velocity outside the boundary layer is constant at 6m/s. 6 × 10-5 m2/s. 009 kJ/kg°C. On this page, you can find the dynamic (absolute) and kinematic viscosity of air at different temperature values in both SI (cP) (cSt) and US customary (lbf·s/ft 2) (ft/s 2) units, taken at 1 atmospheric (atm) pressure. 90 x 10?? Pa·s and a density = 1. pcvry recdoc bfxgh gjoxd rwrbj mvce iql gyl vdcqvdp nyz