Conservation of Energy Data Sheet

Lab 2-Measurement Asynch - Tagged.pdf Page 4 of 7 ? Part I: Taking Measurements & Estimating Uncertainties for a single measurement www.stefanelli.eng.br The mass of the object is_ 0 i Parts on a tripie peam palance 0 0 10 20 30 1 100 2 3 40 200 4 +/- 50 60 70 5 300 7 400 80 Qv Search 8 90 9 500 100 9 10 g www.stefanelli.eng.br

find initial velocity using following equation:

Convert the following using the conversion table attached.

1. The observed and model simulated average daily flow in month flow at the outlet of a river catchment during a given period is presented as follows. Predicted flow Observed flow 0.25 0.30 0.70 0.73 0.80 0.87 0.71 0.90 0.71 0.65 1.60 1.45 0.90 0.70 0.71 0.61 0.24 0.22 1.00 0.64 0.81 1.00 1.05 0.90 0.46 0.48 0.27 0.23 0.80 0.24 0.32 0.42 0.80 0.89 (i) Evaluate the model performance based on any two computed statistical measures of performance of your choice. (ii) Explain possible reasons for model performance observed in (i) above. (Hint: Refer to reading material provided on model evaluation by Moriasi et al., 2007)

Designing safe boilers depends on knowing how steam behaves under certain changes in temperature and pressure. Steam tables, such as the one below, are published giving values of the function V = f(T, P) where V is the volume (in cubic feet) of one pound of steam at a temperature of T (in degrees Fahrenheit) and pressure P (in pounds per square inch). T//P 480 500 520 540 20 22 24 26 27.85 25.31 23.19 21.39 28.46 25.86 23.69 21.86 29.06 26.41 24.20 22.33 29.66 26.95 24.70 22.79 a) Find the tangent plane to V = f(T, P) for T near 520°F and P near 24 lb/in². [Hint: Use the tables to approximate your partial derivatives and recall the equation of our tangent plane is: V = VT(T − To) + Vp(P - Po) + f(T, P) ] b) Use the tangent plane to estimate the volume of a pound of steam at a temperature of 525°F and P near 24.3 lb/in².

Discuss how you might measure the bulk modulus of a liquid.

The following table lists temperatures and specific volumes of water vapor at two pressures: p = 1.5 MPa v(m³/kg) p = 1.0 MPa T ("C) v(m³/kg) T ("C) 200 0.2060 200 0.1325 240 280 0.2275 0.2480 240 280 0.1483 0.1627 Data encountered in solving problems often do not fall exactly on the grid of values provided by property tables, and linear interpolation between adjacent table entries becomes necessary. Using the data provided here, estimate i. the specific volume at T= 240 °Č, p = 1.25 MPa, in m/kg ii. the temperature at p = 1.5 MPa, v = 0.1555 m/kg, in °C ii. the specific volume at T = 220 °C, p = 1.4 MPa, in m'/kg

The stress profile shown below is applied to six different biological materials: Log Time (s] The mechanical behavior of each of the materials can be modeled as a Voigt body. In response to o,= 20 Pa applied to each of the six materials, the following responses are obtained: 2 of Maferial 6 Material 5 0.12 0.10 Material 4 0.08 Material 3 0.06 0.04 Material 2 0.02 Material 1 (a) Which of the materials has the highest Young's Modulus (E)? Why? Log Time (s) (b) Using strain value of 0.06, estimate the coefficient of viscosity (n) for Material 6. Stress (kPa) Strain

The change of SO, concentration with time is shown in Table 1. t(s) [C] 0 1.000000 100 0.778801 200 0.606531 300 0.472367 400 0.367879 500 0.286505 600 0.223130 800 0.135335 1000 0.082085 1200 0.049787 The process is governed by the rate law given by the equation: In (SO), -k+In (SO), Where k is the rate constant and is the time, and In is natural logarithm. By calculating the corresponding values of In [SO,] and plotting the graph of In [SO,] against time, 1, determine the rate constant k of the reaction.

Calculate the absolute uncertainty, fractional uncertainty, and percentile uncertainty

100 80 60 40 20 0.002 0.004 0.006 0.008 0.01 0.012 Strain, in/in. FIGURE P1.17 1.18 Use Problem 1.17 to graphically determine the following: a. Modulus of resilience b. Toughness Hint: The toughness (u) can be determined by calculating the area under the stress-strain curve u = de where & is the strain at fracture. The preceding integral can be approxi- mated numerically by using a trapezoidal integration technique: u, = Eu, = o, + o e, - 6) %3D c. If the specimen is loaded to 40 ksi only and the lateral strain was found to be -0.00057 in./in., what is Poisson's ratio of this metal? d. If the specimen is loaded to 70 ksi only and then unloaded, what is the permanent strain? Stress, ksi

7.8

5.35 Subsonic aircraft use a pitot tube (impact pressure tube) and a static pressure port to determine aircraft airspeed by U = 2Ap Pair 2PH₂8H = where H = Aр/Pнg is Pair the differential pressure expressed in either inches Hg or mm Hg. The value of H can be measured to within 1% (95%) uncertainty. For a measured H of 20 mm Hg, estimate the airspeed and the uncertainty in airspeed at sea level due to H. Use International Standard Atmosphere (ISA) conditions of 15°C and 101,320 Pa abs. For the densities, use PH₂(kg/m³) = 13595-2.57(°C) ±0.1 and treat dry air as an ideal gas so that pair (kg/m³) 3.4837 x 10³p(Pa abs)/T(K) ± 0.001. Neglect the uncertainties in the two densities in the analysis. =

At a pressure of 0.01 atm, determine (a) the melting temperature for ice, and (b) the boiling temperature for water. You might want to use Animated Figure. (a) i °C (b) і °C