Concept explainers
The power available from a wind turbine is calculated by the following equation:
where P 5 power [watts], A = sweep area (circular) of the blades [square meters], ρ = air density [kilograms per cubic meter], and v = velocity [meters per second]. The world’s largest sweep area wind turbine generator in Spain has a blade diameter of 420 feet [ft]. The specific gravity of air is 0.00123. Assuming a velocity of 30 miles per hour [mi/h] and the power produced is 5 megawatts [MW], determine the efficiency of this turbine.
Learn your wayIncludes step-by-step video
Chapter 8 Solutions
Thinking Like an Engineer: An Active Learning Approach (3rd Edition)
Additional Engineering Textbook Solutions
Automotive Technology: Principles, Diagnosis, And Service (6th Edition) (halderman Automotive Series)
Engineering Mechanics: Statics & Dynamics (14th Edition)
Engineering Mechanics: Statics
Mechanics of Materials (10th Edition)
Applied Statics and Strength of Materials (6th Edition)
- T1- Ambient tempeture [k] t- inside tempeture [k] hoo-convective heat transfer coefficient of the air [W/m^2*k] t-thickness of walls[m] Kthermal conductivity (W/m-K) -(VIP) d-cube size [m] Ai-cube area inside [m^2] Ao-cube area outside [m^2] Ts-surface tempeture[k][ E-emissivity aluminium foil - Stefan Boltzmann constant W·m-2 K-4 303 290 10 0.08 0.007 1 6 6.96 300 0.03 5.67E-08 Q heat flux [W] ΔΤ ΣR F T₁ 111.0 0000 006%arrow_forward1.1 s) The overall size of the system (i.e. the shell) is 5.8 inch ID and a 27-inch long tube section. Assuming tubes are 1/2 inch in diameter (ignore thickness) and that the tubes are spaced with 1/4 inch between them. Estimate the number of tubes that will fit in the shell. O 36 O 60 O 13 O 46 QUESTION 2 1.22 area [ft²]. Og ft² 5 ft² O 17.66 ft2 10.6 ft2 Regardless of your answer to part 1.1, use 36 as the number of tubes and estimate the total heat transferarrow_forwardAn automobile's power is proportional to the cube of its speed on a level road in still air. This relationship between speed and engine power for the Gofaster model XP9 is: [mph]3 = 9600 [hp]. The XP9 has a 180 hp engine. What is its max speed on a level road in still air?arrow_forward
- Consider the piston-cylinder assembly shown below. Heavy weights are added to the piston, compressing the gas. Assume that the gas reaches an internal pressure of 1.5 bar after the compression is done. The pressure outside the piston-cylinder is 1 bar. We also know that the piston diameter is 20 [cm.] With how much force doe the gas push upward on the piston (in Newtons?) Weights Piston System boundary Gas Ро garrow_forward|The following processes occurs in a rever sible thermodynamic cycle: 1-2: Reversible polytropic compression at pressure X)bar at volume Y)m' to a pressure [Z]bar and specific volume (A]m'/kg. The index of compression may be taken as n. 2-3: Reversibly expansion with expansion index of 2 to pressure [B/bar. 3-1: Reversible cooling at constant volume to the initial state.arrow_forwardAn ideal gas with a mass of 2 kg reversibly and polytropically expands up to 3 times its initial volume in a piston-cylinder assembly. The temperature of the ideal gas drops from 300 ° C to 60 ° C. a) The heat energy input is 20 kJ and the boundary work output is 100 kJ. Find the specific heats cv [kJ / kgK] and cp [kJ / kgK] for the gas. b) If the heat energy output is 20 kJ and the boundary work output is 100 kJ, calculate the specific heats of the gas cv [kJ / kgK] and cp [kJ / kgK]. c) Find the value k, which is the ratio of specific heats. d) If the heat energy input is 20 kJ, the boundary work output is 100 kJ and the entropy generation is 0.36 kJ / K, calculate the thermal energy source temperature as [° C].arrow_forward
- A Venturi Tube develops low pressure on its throat, which can suck water from a deposit located under it. Assuming permanent flux with no losses, calculate the V1 necessaryto suck water from the deposit to the throat. D1 = 15 [mm]; D2 = 37 [mm]; h = 163 [mm]; pa = 101325 [Pa] (atmospheric pressure). Express the solution in [m/s]arrow_forward1500 W of power is input into a fluid with mass 15 kg and specific heat capacity of 3.2 kJ/[kg K]. What is the heating rate of this fluid assuming heat losses are negligible and there exist no changes in the pressure of the system? 1.875 K/min 0.03125 K/min 1875 K/min 45 K/minarrow_forwardphysical quantities m, r, u, a, and t with dimensions [m] = M, [r]= L, [v] = LT, [a] = LT-2, and [t] = T. Enter the dimensional expression of the quantity on the right-hand side of each equation. Your answers may contain only M, L, T, and exponents. Assume that each of the following equations is dimensionally consistent. F = ma [F] =arrow_forward
- A particle is subjected to the action of two forces: F1 = 2.5 i-3j+ 6 k [kN] and F2 = 5 i+6j-5k [kN]. The magnitude of the resultant force is: %3D %3D Select one: Oa. FR=-8.139 [kN] %3D Ob. FR 8.139 [kN] Oc. FR = 5 [kN] Od. FR=-5 [kN] Activate Win ype here to seatch 445 PEarrow_forwardA. The flow of liquid from a tank in a manufacturing system has been modeled using the following equation: q(t)=ke(t)√h(t) where: q(t) is the rate of liquid flow out of the tank [m³/s] (1) is the position of a valve at the outlet of the tank [% open] h(t) is the height of liquid in the tank [m] k is a constant Obtain a linearized equation describing the flow rate q(t) as an approximate function of change in valve position 8(t) away from a nominal valve position 8, and change in liquid height h(t) away from a nominal liquid height ho.arrow_forwardm [kg] 4/₂ [m] SH с E Ctiven: m = 42kg L 57 B L[m] 15° A If AB and CB is taken as 1.1 [m]. 4/35 m [kg] k have Lengths of 0.305 [m] and Find the moment of force acting at point Azarrow_forward
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY