Most important topics in Mechanical Engineering

I'd suggest you to develop a very strong understanding of basic subjects like - mechanics, thermodynamics and manufacturing processes.
Later on, when you will start developing interest in some specific field, then you can master in subjects pertaining to that particular field.

Concentrate on mechanics and thermodynamics. these are the pillars of this branch.
the others are design concepts, manufacturing technology and materials science.

in higher semesters give importance to machine dynamics, and finite element analysis.

heyyyy thanxxx a lot dude 😀😀😀

So, since this is something that a lot of people are searching for and coming to CrazyEngineers, I think we all should do our bit in making this discussion more useful and important.

Here is a list of the basic terms that every mechanical engineer should know. Anyone here wants to take a lead in explaining some of them?

You could just give out one liner simple definitions so that other beginners can benefit from this one-stop content.

1. Torque or Turning Force
2. Couple
3. Moment
4. Stress
5. Strain
6. Spring
7. Specific Weight
8. Specific Volume
9. Specific Gravity
10. Specific Heat
11. Viscosity
12. Buoyancy
13. Discharge of Fluid
14. Bernoulli's Equation
15. Device for Fluid
16. Mach Number
17. Hydraulic Machine
18. Draft Tube
19. Thermodynamics Law-
zeroth law
First law
second law
20. Entropy
21. calorific value of fuel
22. Boiler/Steam Generator
23. Superheater
24. Air Preheater
25. Boiler Draught
26. Nozzle
27. Scavenging
28. Supercharging
29. Turbocharging
30. Governor
31. Flywheel
32. Rating of fuel-
S.I. engine
C.I. engine
33. Stoichiometric Mixture/ Stoichiometric Ratio
34. Heat Transfer
35. Thermal Conductivity
36. Heat Exchanger
37. Refrigeration
38. 1 tonne Refrigeration
39. Humidification
40. Dehumidification
41. Gear Train
42. Gyroscopic Couple
43. Heat Treatment
44. Ferrous-Metal
45. Non-ferrous metal
46. Allowance
47. Tolerance
48. Clearance
49. Stiffness
50. Toughness
51. Fatigue
52. Nuclear Fission
53. Nuclear Fussion
54. Welding
55. Machine Tool
56. Cutting Tool
57. Indexing
58. Jig
59. Fixture

The list is too big. I will explain a few of them, at random, rest of them will be taken care by other mechies:

1.) Torque: It is a rotating force, which tends to rotate a body about an axis. it is expressed as the force multiplied by the distance between the force and the turning point.

3) Strain: the ratio of the deformation caused in the body, when the load is applied, to the original dimension.

19) second law of thermodynamics: The efficiency of no machine is cent percent.

55) machine tool: machines used for manufacturing components, by means of material removal process example : lathe, milling, shaper,etc.

56) cutting tool: the tools used in the machine tools . example: drill bits, milling cutter etc.

more:

44) ferrous metal: alloys of iron and steel

45) non ferrous metal: example: aluminum, copper etc.

58) jig: a stencil or pattern like device, used for speeding up the process while cutting holes, or other features, on a large number of jobs (amounting to around 1 lakh pieces)

30) governor: a mechanical speed controlling device, operating on the principle of centrifugal force.

27) scavenging : the process of removal of the residual exhaust gas in an I.C engine cylinder, by mixing it with some fresh intake air.

28) supercharging: the process of increasing the volumetric efficiency of an I.C engine, by compressing the intake air. the compressor used here is crankshaft driven.

29) Turbocharging: same as supercharging. here the compressor is driven by a gas turbine, which in turn is powered by the exhaust gas from the engine.

23. Superheater - it's function is to heat the steam and to make it as dry as possible

That's great #-Link-Snipped-# and #-Link-Snipped-# Please let us complete the list folks. 😀

20. Entropy-
The second law of thermodynamics gives a precise definition of a property called entropy. Entropy can be thought of as a measure of how close a system is to equilibrium; it can also be thought of as a measure of the disorder in the system. The law states that the entropy—that is, the disorder—of an isolated system can never decrease. Thus, when an isolated system achieves a configuration of maximum entropy, it can no longer undergo change: It has reached equilibrium. Nature, then, seems to “prefer” disorder or chaos. It can be shown that the second law stipulates that, in the absence of work, heat cannot be transferred from a region at a lower temperature to one at a higher temperature.

36. Heat Exchanger

Heat exchange is a natural phenomenon occurring throughout our environment. It drives the weather cycles and energy exchange between ecosystems. Harnessing its utility through accurate control of heat exchange has been a focus of our industry for over a century.

Heat exchangers allow control over the dynamics of heat transfer between fluids. They are used in widespread applications, such as solar heating, pool heating, domestic water heating, radiant floor heating, food processing, marine applications, general industrial process control, and more

Below are parametric thermodynamic equations that define the nature of heat exchange and performance of a heat exchanger for any given application. Once these thermal parameters are determined they can be used to calculate heat exchanger performance in order to select the most suitable product based on the specific application.


Theoretical Heat of a Fluid

The heat transfer principal in heat exchangers is based on a colder fluid gaining heat from a relatively hotter fluid separated by, and flowing over, a heat conductive material.
This is expressed by the following formula:

(eqn 1)

Q = Total heat load
m = Mass flow rate of fluid.
cp = Specific heat of fluid at constant pressure.
DT = Change in temperature of the fluid.

This formula provides the Theoretical Heat Yield to or from a given fluid undergoing a temperature change, DT at a mass flow rate, m with the fluid’s specific heat property, cp.


Practical Heat Transfer Control

The theoretical heat yield of a fluid gives the amount of heat that needs to be transferred into or from a fluid. The practical heat transfer is a function of the physical geometry of the heat exchanger, its material composition, and the fluid condition.

The general form of the equation defining the maximum potential heat transfer through a heat exchanger is expressed by the formula:

(eqn 2)

U = Overall heat transfer coefficient
A = Surface area
LMTD = Logarithmic mean temperature difference

The Practical Heat Transfer Control is determined by the molecular thermodynamic interactions between the fluids flowing through the heat exchanger and the geometry of the heat exchanger itself.
The overall U value is calculated by an equation specific to the geometric configuration of a Heat Exchanger. It is a function derived using dimensionless numbers such as Reynolds Number (Re), Prandlt Number (Pr), along with fluid flow parameters. The overall U value is calculated over the total surface area A of the heat exchanger, across which the fluids exchange heat.

The log mean difference of the inlet and outlet temperatures (LMTD) of the hot and cold fluids for a counter flow exchanger is expressed by the formula:

(eqn 3)

Thi = Inlet temperature of hot fluid
Tco = Outlet temperature of cold fluid
Tho = Outlet temperature of hot fluid
Tci = Inlet temperature of cold fluid

Practical heat exchange value, Qp, can be compared to the theoretical, Qt, value to determine if the heat Exchanger has enough capacity to fulfill the application requirements.

30. Governor
A governor, or speed limiter, is a <a href="https://en.wikipedia.org/wiki/Machine" target="_blank" rel="nofollow noopener noreferrer">Machine</a> used to measure and regulate the <a href="https://en.wikipedia.org/wiki/Speed" target="_blank" rel="nofollow noopener noreferrer">Speed - Wikipedia</a> of a <a href="https://en.wikipedia.org/wiki/Machine" target="_blank" rel="nofollow noopener noreferrer">Machine</a>, such as an <a href="https://en.wikipedia.org/wiki/Engine" target="_blank" rel="nofollow noopener noreferrer">Engine</a>. A classic example is the <a href="https://en.wikipedia.org/wiki/Centrifugal_governor" target="_blank" rel="nofollow noopener noreferrer">Centrifugal Governor</a>, also known as the <a href="https://en.wikipedia.org/wiki/James_Watt" target="_blank" rel="nofollow noopener noreferrer">James Watt</a> or fly-ball governor, which uses weights mounted on spring-loaded arms to determine how fast a shaft is spinning, and then uses <a href="https://en.wikipedia.org/wiki/Proportional_control" target="_blank" rel="nofollow noopener noreferrer">Proportional Control</a> to regulate the shaft speed.

some more info

#-Link-Snipped-#

22. Boiler/Steam Generat

Focus on thermodynamic & machine tools rules of motion 😀
Etc ...

Hi,
I am Ajith, I have doubt in shell tube heat exchanger that is if we introduce a fin on the walls of tube can the heat transfer rate be increased

Mechanical important topic

#-Link-Snipped-# Did you go through all the topics shared above in the discussion? Are you looking for something specific?

Such important topics for mechanical engineering can be useful for cracking an interview or viva for students.

Here goes my list -

1. Carnot Cycle, Otto Cycle, and Diesel Cycle
2. MPFI and TPFC systems
3. Laws of Thermodynamics
4. 4-stroke and 2-stroke engine mechanisms.
5. SI and CI engines
6. Turbo charging Vs. Supercharging
7. Jet Propulsion, Ramjet, Scramjet, Turbojet, Turboprop, and Turbo fan
8. Refrigerator system
9. Heat Exchangers
10. Stephan-Boltzmann Laws, Kirchoff's Law, Planck's Law and Wien's Displacement Law.
11. CDI, ball pistons, camless engines like GDI, VTEC
12. ABS, ESP, SBC, SOHC, and DOHC explanations
13. CNC and DNC machines
14. Cooling fluids and their functions
15. Heat treatment processes
16. Hook's law
17. Euler's theory
18. Bernoulli's theorem
19. Six Sigma
20. Basics of thermodynamics

After I started writing this list, I think I realised that the topics are way too many to list. Good job by @zaveri in listing above definitions.