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Mechanical Engineering

Radiation

5. Determine the fraction of the radiation leaving the base of the cylindrical enclosure shown attached that escapes through a coaxial ring opening at its top surface. The radius and the length of the enclosure are r_1 = 10cm and L = 10cm, while the inner and outer radii of the ring are r_2 = 5 cm and r_3 = 8cm, respectively.

Weld analysis

Two steel plates are joined with a butt weld using a weld throat h of 3/8 in. and the length of weld 1 of 4in. How do I determine the shear stress in the weld for a shearing force of 15000 lbf?

Midrange and amplitude components

A shaft is subjected to a completely reversed bending stress such that Xmax=40kpsi and Xmin=-40kpsi. How do I determine the midrange component and the amplitude component? (X=sigma)

Endurance limit

A steel rod AISI 1018 has the rotating bending specimen's endurance limit of 32.2kpsi. How do I determine the endurance limit for the part if the Marin modifying factors are: ka=0.887, kb=1, kc=0.889, kd=ke, kf=1?

Endurance limit

A steel rod AISI 1040 has the ultimate tensile strength (Sut) of 113kpsi. How do I determine the rotating bending specimen's endurance limit at 10^6 cycles?

Principal stresses

The state of plane stress at a point in a member is zx=-20MPa, zy=90MPa, txy=60MPa. How do I find the principal stresses zx and zy?

Modulus of Elasticity

A linear isotropic material has the shear modulus of elasticity G of 11.5*10^6 psi and the Poisson's constant v of 0.3. How do I determine the Young's modulus of elasticity E?

Tensile stress

A 3.14insq. cross sectional area steel tension rod carries a load of 3140lbf. How do I calculate the tensile stress in the rod?

Hoop stress

1. A pressure vessel is made of a cylindrical composite part produced by filament winding. Hoop winding is used in which the number of winding layer is 5 and the wall thickness for each layer is 1mm. The diameter of the vessel is 0.5m. The fiber material is known to be S-glass with a tensile strength of 4.5GPa, and the matrix m

Single degree of freedom vibration problems with forcing functions

Need help with this Undergraduate problem where two dampers are in series. For a vertical spring/damper system with mass (M) and a harmonic forcing function, Fmax Cos [omega x t] , two dampers are in series with coefficients, C1 and C2, and a single spring with constant, k. Determine the amplitude of the steady-state disp

Angular Velocity: Slender Bar, Stepped Disk and Slender Rods

Please see the attachment for proper formatting and diagrams. 1. The slender bar with a mass of 4 kg is released from rest at an angle of 35 degrees. What is the angular velocity of the bar when it is vertical? a. 0.667 rad/s b. 1.06 rad/s c. 0.888 rad/s d. 1.74 rad/s e. 2.31 rad/s 2. The stepped disk

Manufacturing processes factors

1. Explain the factors involved in selecting the appropriate type of abrasive for a particular grinding operation. 2. What are the consequences of allowing the temperatures to rise during grinding? (Q. 25.38). 3. What are the implications of using a smaller abrasive grain size (higher grit number) in a bonded grinding wheel?

Moment of Inertia Problems

The three problems attached having to do with moment of inertia of things like a yo-yo. I need help setting them up. Please send explanations with the answer so I can see how your answer was achieved.

Mass of Inertia and Angular Acceleration

1. Two slender rods are welded together at right angles and released from rest as shown. The two welded bars rotate freely around point C. Each bar is 10 lbs and is 1.5 ft long. At release, what is the acceleration magnitude of point B? 2. A vertical 0.2-meter-long slender bar with a uniform cross section is released from res

Manufacturing Processes

Please answer the following questions: Certain manufacturing processes have the following characteristics described below. Please characterize the process in terms of : Type of process, state of workpiece material and the type of process energy used. 1. A metal is cast into a mold and solidifies 2. A metal bar is reduce

Mechanical Vibration Analysis

For this two degree fo freedom model, how do I find the matrix equation of motion? How do I find the value of the modal ratios if m1=m2=m, k1=k and k2=3k? If a force of 25sin3t is applied to m2, how do I find the value of the response if m1=m2=1 slug, k1=10lb/ft and k2=30lb/ft?

Mechanical Vibration Analysis

How do you find the equation of motion for an idealized model? For this model how do you find the periodic time (time in sec) and the natural frequency (rad/sec)? Please see attached for diagram.

Turbomachinery and Reaction Turbines

1) Steam at 15 bar and 350 degrees C is expanded through a 50% reaction turbine to a pressure of 0.14 bar. The stage efficiency is 80% for each stage and the reheat factor is 1.05. The expansion is to be carried out in 10 stages and the required power is 6000 kW. Calculate the steam flow required, assuming that the stages all de

Turbomachinery: Reaction Turbines

Please help with the following problem. Sketch the fully annotated velocity triangles for a Parsons turbine stage. Use your sketch to show that the specific work produced per stage is given as w_stage = (C_b)^2 [1 + 2(f/C_b)(cot(B_1))]. At a particular stage of a Parsons reaction turbine, the mean blade speed is 60 m/s an

Turbomachinery: Impulse Turbine

1) The steam from the nozzles of a single wheel impulse turbine discharges with a velocity of 600 m/s at an angle of 20 degrees. The blade wheel rotates at 3000 rev/min and the mean blade radius is 590 mm. The axial velocity of the stream at the exit from the blades is 164 m/s and the blades are symmetrical. Sketch the annota

Mass Moment of Inertia and Translational Motion

1. Calculate the mass moment of inertia about the x axis. The total mass of the object is 13 kg. 2. The plate with two holes is made of steel with a density of 7800 kg-m3. The radius of each hole is 5 cm. Determine its mass moment of inertia about the z-axis. 3. Determine the mass moment of inertia about the y axis. The t

Moment of Inertia and Translational Motion

1. A four-wheel truck that has a mass of 5,000 kg accelerates forward. The coefficient of friction for the front and back wheels is 0.2 and 0.4, respectively. What is the acceleration of the truck? Assume that the friction force on both the front and rear wheels are at a maximum and both are about to slip. 2. Each of the 2 b

Turbomachinery: Impulse and Reaction Turbines

1. An impulse air turbine rotor with a blade speed (U) of 300 m/s is measured to have a relative rotor inlet velocity (W_1) of 750 m/s at an angle of 69 degrees and an outlet relative velocity (W_2) of 660 m/s. Th temperature and pressure in the rotor are 375 K, 0.83 bar. Calculate the rotor efficiency, rotational speed and powe

Calculating the Second Moment of Area

It is necessary to design a square-section composite bar that will withstand an applied load without deflecting more than a specified amount.The design specification for the bar, including its dimensions and loading criteria, is given below. Using the formula below, calculate the second moment of area of the bar and use this

Plot Curve for Amplitude of Vibration; Determine Amplitude

A schematic of a horizontal shaker is shown in figure 1 {see attachment}. The shaker consists of a mass supported on four thin, rectangular springs. The springs are L=200mm long, w=50mm wide and t=4mm thick. The Young's modulus for the springs is 200 GPa. The mass is coupled to the ground via a damper with damping factor C=894Ns

Solve for Force (Engineering Dynamics)

Two forces act on a slender bar that is pinned at (see attachment). The horizontal reaction at 0 is 5 lb to the right, the force F in lb is closes to which answer choise? a) 25 b) 30 c) 15 d) 27 *Please see attachment for equations and diagram

Dynamics Problem - Backspin (Friction, Velocity)

A 1.2ft diameter ball is thrown onto a rough surface, such that it has a velocity of 6ft/s and a backspin angular velocity of w. If it is to stop backspinning at the same instant as the velocity is 0, the backspin w in rad/s is what? HINT: The answer is independent of the mass and coefficient of friction. a. 17.8 b. 22.0 c. 2

Calculating maximum velocity, displacement and stretch

The pair of blocks, which are connected by a cord, are released from rest when the spring is unstretched. The static and kinetic coefficients of friction are .2 and .1, respectively. The following things are to be found using the work-energy methods: 1) Maximum Velocity of the blocks 2) Stretch of the spring at the maximu

Thermodynamics Problem: Heat Pump

Hi, I am confused about how to answer the following question. Any assistance would be appreciated. Question: A heat pump with a COP (coefficient of performance) of 2.8 is used to heat an air-tight house. When running, the heat pump consumes 5 kW of power. If the temperature in the house is 7 degrees Celsius when the heat pum