Water (cp=4179 J/kg·K) at 30 °C flows on the inside of a steel tube with 25 mm inner diameter and 0.4 mm wall thickness at a flow rate of 0.4 kg/s. The tubes forms inside of a counter flow double pipe heat exchanger. Engine oil at 100 °C flows in the annular space with a flowrate of 0.1 kg/s. The outlet temperature of the oil is 60 °C. The material of the heat exchanger is carbon steel with k=45 W/m·K. The inner diameter of the outer tube is 55 mm. If the length of a hairpin is 5m, calculate the number of hairpins ignoring the fouling resistances.

please can you help me course name heat exchangers.

Air enters the compressor of an ideal cold air-standard Brayton cycle at 100 kPa, 300 K, with a mass flow rate of 6 kg/s. The compressor pressure ratio is 10, and the turbine inlet temperature is 1400 K.


For k = 1.4 and C_p = 1.005 kJ/kg, calculate:

(a) the percent thermal efficiency of the cycle.

(b) the back work ratio.

(c) the net power developed, in kW

What fluid property is responsible for the develop­ment of the velocity boundary layer? Explain in detail.

A rectangular car tank 20m long, 4m wide and 3m deep is completely open at the top. If it is initially filled to the top: (a) How much liquid will be spilled if it is given a horizontal acceleration of 0.3g in the direction of its length? (b) What is the maximum hydrostatic force acting on the side opposite the direction of the acceleration. (c) Determine the volume of the remaining water at the tank.

nterpret the following NC program block by block. Indicate G and M functions for each block, describe the tool movement and its path also.

N010 G90 G70 M03 S1200 T05

N020 G00 X0.375 Y0.875

N030 Z0.1

N040 G01 Z-0.1 F10.0 M08

N050 X2.0 F20.0

N060 G02 X2.375 Y0.5 I0.0 J-0.375

N070 G01 Y0.375

N080 X3.625

N090 Y1.25

N100 X3.5

N110 G02 Y1.875 I0.0 J0.375

N120 G01 X3.625

N130 Y2.625

N140 X2.375

Explain the finite element method for stress analysis as you would to a high school student who is interested in becoming an engineer. Note that this could be the deciding factor for the student to choose Engineering at University. As such keep your answer relevant, interesting and succinct (furthermore, the student is young so they get bored easily...).

[Word limit: 200]

Infrared Soldering

(FOR REPORT PURPOSE)

1. Synopsis
2. Introduction (Applications/Industries)  
3. Mechanism and Metallurgy

Derive the formula (together with diagram/s where applicable) for the critical load of an eccentric loading conditions.  

Why is three wire method preferred for measuring the effective diameter of thread over two wire method? derive mathematical equation of with worth thread

Students will design a mutually operating gear system under the conditions given in this question. (Sizing will be done as a result of calculations according to working conditions, material, construction status and strength). In this design, shaft and bearing calculations will not be made. Only mutual gears will be designed according to the data and acceptance. The student will make assumptions for the values and information that are not given and will explain why he made this assumption.

Input Power: 8 Kw

Input Cycle : 1224

Cycle Rate: 4

Gear Material: 1050 Steel

A high carbon steel shaft is used in an engine and subjected to different loads. In order to
analyse the stress in the shaft, consider a rectangular element within the material. This
element is subjected to compressive stress of 135 MPa and shear stress of 166MPa in the
vertical direction. The compressive stress in the horizontal direction is 176MPa with a shear
stress of 115MPa.
a. Sketch the state of stress on this element.
b. Determine the maximum and minimum normal and shear stresses and their plane of
orientation.
c. If the yield strength of the material is 350MPa, Poison’s ratio is 0.32, and factor of
safety is 5, determine the diameter of the shaft to avoid failure.
d. What will be the difference in the analysis above if there is an additional torsional
load (T) and bending moment (M).
e. Show how you can use any theory of failure to design this shaft.
f. What are the challenges of applying the theories of failure in actual engineering
practice and as a design engineer, how would you deal with these challenges.

A simple R134a plant is develop 70000kJ/hr of refrigerant leaves the evaporator as saturated vapor at 10 degree c. After isentropic compression the pressure of refrigerant is 10 bar. Draw the P-h diagram and determine 1) the refrigerant flow rate 2) the compressor discharge temperature 3) the heat rejected to the condenser in KW 4) The COP 5) the power required to drive the compressor

Why do we may avoid normal shocks when designing aircraft geometries?