An oil cooler is in the form of a single shell 4 tube heat exchanger in which oil passes through the tubes and cool water passes through the shell. Water comes in at 15C and leaves at 25C and has a mass flow rate of 20 kg/min. Oil enters at 35C with a mass flow rate of 30 kg/min. C_p of oil is 2.13 kJ/KgC and that of water is 4.18 kJ/kgC. If the surface area of the heat exchanger is 0.5 m², calculate the overall heat transfer coefficient. Assume the heat exchanger is adiabatic with regards to the surroundings.

how can i redesign a simple bench vise inorder to decraese the total assembly time in solid works

The cantilever is affixed to the free end of a square cross-section piezoelectric (PZT) block, which is fixed at the other end. Draw the schematic of the lumped-parameter model of the cantilever-PZT system, obtain the mathematical model of this mechanical system, and derive the lumped mass and stiffness of the PZT knowing that la = 0.01 m (length of PZT block), a = 0.005 m (side length of PZT cross-section), EPZT = 55 GPa (Young’s modulus), ?PZT = 7500 kg/m3 (mass density). The piezoelectric material losses are represented by an equivalent viscous damping coefficient cPZT = 60 N-s/m.

Compare how Griffith determined critical crack length, ac, with how the value of r*is determined in the solidification process.

Water at 50 °F is being transported from one open reservoir to another open reservoir using a concrete pipe. The two reservoirs are 1.5 miles apart with a difference in surface elevations of 25 ft. Determine the minimum pipe diameter needed to carry 10 ft3 /s of water.

(Chapter 15)

Q: Please give an example of creep.

3.0 kg of air initially occupying a volume of 0.01 m3 at a pressure of 95.0 bar expands in a piston-cylinder assembly isothermally and without irreversibilities until the volume is 0.05 m3. Using the Redlich-Kwong equation of state, determine the

1. temperature during the process, in K

2. final pressure, in bar

Materials are subject to changes from temperature. We know there are several states of matter: solid, liquid, gas, and plasma. However, within a solid-state, materials have their properties affected, in particular brittleness. The Liberty ships of the Second World War were often breaking from cold weather.

These failures highlighted a material fracture problem.

What causes these failures, what materials are affected, and are there any that are not? How is brittleness calculated and measured (types of measurement) and what does this means for aircraft material selection and design considerations? You may include the influence of this problem from a maintenance perspective.

Your report of a minimum of 2,000 words is due for this assignment.

A spherical motile bacteria with a radius of 1.0 microns and a density approximately equal to water is swimming in water (temperature 20 C) at a speed of 8.0 microns per second. The bacteria suddenly stops swimming. Since the Reynolds number for a swimming bacteria is small, it should experience Stokes drag (F?_D? = 6????Rv).

(a) How long (in seconds) does it take the bacteria to come to a “complete” stop? We’ll define a “complete” stop to be when the speed has dropped to 25.0 nanometers per second.

(b) How far (in meters) does the bacteria coast in this time?

This is problem 6-19 from El-Wakil’s Powerplant Technology book -- a 35,000 lb_m/h double-effect evaporator receives motive steam at 40 psia and 300°F. Pretreated raw water enters at 60°F. The pressure in the second effect is 5 psia. Calculate, for equal heat heads, (a) the amount of motive steam required, in pound mass per hour, and (b) the surface areas for each evaporator, in square feet.

A vestibule type rotating door for a large business has three panels, each 6 feet wide and 8 feet high has 400 people passing through every hour. The panels are fitted with an average of 1/64 inch crack all the way around and the expected maximum pressure differntial between the inside and the outside is 0.288 WG. Estimate the infiltration of exfiltration.

(show work)

2 If you deposit $1,000 now and are promised payments of $500 three years from now and $1,500 five years from now, the equation that will yield the correct rate of return is:

   A)   -1000 = 500(P/F,i,3) + 1500(P/F,i,5)

   B)   0 = 1000 + 500(P/F,i,3) + 1500(P/F,i,5)

   C)   1000 = -500(P/F,i,3) - 1500(P/F,i,5)

   D)   0 = -1000 + 500(P/F,i,3) + 1500(P/F,i,5)

3 For the equation: 5,000 = 1,000(P/F,i,1) - 2,000(P/F,i,2) + 7,000(P/F,i,7) + 7,000(P/F,i,9), the number of possible rate of return values is:

   A)   1

   B)   2

   C)   3

   D)   4

4there is more than one sign change in the net cash flow of a rate of return equation, the possible rate of return values will fall in the range of:

   A)   minus infinity to plus infinity

   B)   minus 100% to plus infinity

   C)   minus 100% to plus 100%

   D)   minus infinity to plus 100%

5 When multiple rate of return values are possible for a rate of return equation, one way to come up with a single value which satisfies the equation is:

   A)   Solve for the internal rate of return

   B)   Use the project net investment procedure

   C)   Eliminate all rate of return values above 100%

   D)   Eliminate all rate of return values below 0%

1. Describe the purpose of design guideline of VDI-2206 and VDI-2221.

2.Describe how VDI-2221 and 2206 can be implmented concurrently

3. Describe importance of developing a function block diagram in context of systematic design

Solve the following equations using the Newton-Raphason method. ( using matlab)

x^2+x*y^2 = 9

?3x^2 * y - y^3 = 4   

?initial estimation of (x,y) = (1.2, 2.5)

?please help.. using matlab and matlab code

An 8 in. diameter grinding wheel, 1 in. wide, is used in a surface grinding operation performed on a flat piece of low carbon steel. The wheel is rotating with a surface speed of 5,000 fpm, depth of cut of 0.002 in./pass and cross feed (w) of 0.15 in. The reciprocating speed of the workpiece is 20 ft/min., and the operation is performed dry. Letting C = 300 per in2 and the ratio of chip width to average undeformed chip thickness equal to 20, estimate the undeformed chip length. Estimate the undeformed chip thickness. Calculate the required grinding power in lb*in/min. What is the amount of cutting force required for this operation?