Introduction to Mechanical Engineering Subjects and Applications

As a student of mechanical engineering I was always curious and interested from start of my engineering studies that why a mechanical engineer has to study particular  subject, where and how studied subjects will be helpful for him.  what will be the application of these subjects and how these subjects should be studied and applied in the real world. If you have the same questions in mind then let us explore the subjects and then understand their importance, one by one. As a student of mechanical engineering everybody learns more or less of following subjects:

1. Engineering mathematics.
2. Engineering graphics and drawing.
3. Numerical Methods.
4. Applied mechanics.
5. Strength of materials.
6. Theory of machines.
7. Design of machines.
8. Fluid mechanics.
9. Hydraulic and Pneumatic machines.
10. Thermodynamics.
11. Heat and mass transfer.
12. Automobile Engineering.
13. Material science.
14. Production engineering.
15. Manufacturing technology.
16. Industrial Engineering & Management.
17. Metrology and quality control.

(Note: Above list may vary based on the university and curriculum. But generally speaking everybody learns more or less the same subjects).Now, Let us explore one by one:

• Engineering Mathematics:

Every engineer is a mathematician first and then an engineer. Mathematics is the language of technology enthusiast. Yes, it is true! Mathematics is the one of the fundamental subjects of every engineering stream. Study of mathematics helps to understand how the engineering concepts are derived and how mathematical tools can be used to solve engineering problems. Generally speaking, for any research and development  work there is a need of mathematical tool to interpret the results, to carry out the analysis and to develop the possible approach for problem solving.

• Engineering Drawing:

It is the first language of every mechanical engineer. An engineer communicates, expresses his ideas, his work through the language of engineering drawings. Engineering graphics and engineering drawings are one of the most fundamental and essential subjects for every engineer. Without knowledge of this subject mechanical engineer can not work in field. This subject teaches how to draw a machine. How to read and understand the information through drawings. How to interpret and understand tolerances; concepts like concentricity, run out, etc. In every industry they use engineering drawings for communication and representation of design concepts, production, structural analysis, etc. An engineering student should spend a good amount of time and master this subject as this is one of the very interesting and widely used subjects in engineering field.

• Applied Mechanics:

Applied mechanics is the first subject in mechanical engineering curriculum which introduces the basic concepts about the force,moments, stress, rigid body, centroid, center of gravity, friction, etc . In this subject basically we learn how to calculate resultant of the all forces applied on a rigid body, to resolve forces in its directional components. We learn to draw FBD (free body diagrams). In short it is the subject where we explore the type and effects of applied forces on the body and their effects resulting the motion , friction, displacement etc.

• Strength of Materials (SOM):

After learning the basic concepts of mechanics we learn about internal forces developed in mechanical body (element) in strength of materials. It deals with types of stress and strain induced in specimen body due to applied external force. It deals with relation of physical strength of body , externally applied force (mechanical or thermal ) and deflection/elongation/contraction that happens in the body. We learn few basic concepts about strength, strain,stress, resilience, strain energy, bending stresses, types of beams,deflection in beams, torsion in shafts, buckling etc.

• Theory of machines (TOM):

Theory of machine deals with the relationship of motion, forces,connections between two or more components in a machine or mechanism. in this subject we learn the force transmission from one part (element) of the machine to the adjacent part in the contact. we learn basic concepts about mechanisms (types, chains,links,elements, pairs, rules of mechanism, degree of freedom, inversion of the mechanism etc). We also study the effect of force and its effect on the motion of the elements in the mechanism (kinetics and kinematics. displacement, acceleration, jerk etc.)This subject also deals with some part of vibration and dampening.

• Design of machine (DOM) :

Design of machine is one of the vast subjects in mechanical engineering. here we collectively apply learning from mechanics, SOM, TOM and few design rules, principles for designing the machine components. We learn how to decide the dimensions, select materials, select standard components, how to use design data books, standards used for designs, factors considered for design, make changes for special arrangements, aesthetics and ergonomics of mechanical components. Design is like the art of the mechanical engineer (Designer).

• Fluid Mechanics:

Fluid mechanics is about study of forces acting on fluid and its behavior. This subject covers the understanding of properties of commonly used fluids (like air, water), variation of these properties with respect to the external conditions applied (pressure, temperature, externally applied forces). The subject is broadly divided into study of fluid at static (fluid statics) and fluid in motion (Fluid dynamics).  The subject also introduces the principles and governing equations to design and understand the working of fluid machines and structures like pipe/channel design, hydraulic turbines, hydraulic pumps, etc.

• Hydraulic and pneumatic machinery:

This subject introduces us basic working of hydraulic and pneumatic machines. Subject covers the different components used for force transmission and  fluid flow control through mechanical and fluid links. It helps to understand us how pressurized fluid can be used to do work efficiently. In hydraulic and pneumatic machines we learn mostly - hydraulic press, gear pumps, piston and cylinder pumps and actuators (Linear actuators), hydraulic accumulators, pressure and flow control valves, direction control valves, filters, strainers, moisture separators, air motors,compressors, etc.

• Thermodynamics:

Thermodynamics is about heat and work interaction and its governing laws. This subject deals with the learning obtained through observations and obvious conclusions about how the heat and work energy conversions happen. In this subject we learn about theoretical concepts about heat engines, refrigerators, types of power generation cycles (Otto cycle, Diesel cycle, Rankine cycle, ), types of work consuming cycles (refrigeration cycles, vapor absorption cycles ). We learn about conservation of energy principle, its applications; We learn about concepts about limitations of maximum possible work extraction from any heat source. (Second law of thermodynamics, Availability, Exergy, entropy etc.)

• Heat and mass transfer:

Thermodynamics cover the basics of heat and work interaction but it does not answer the question for how much heat transfer is required with respect to time. Or, at what rate heat should be given to achieve desired output. Heat transfer and mass transfer covers these topics along with laws of heat transfer and mass transfer. In heat transfer basically we learn how does heat is carried through different mediums (solids and fluids, heat transfer at boundary of solids and fluids), radiation. In addition we learn to design heat different types of transfer units (heat exchanger), we learn about heat transfer during condensation and boiling phenomenon. In mass transfer we explore about the diffusion of the mass and laws related with mass transfer. The knowledge of heat transfer is very important to design any thermal equipment.

• Automobile engineering:

As a kid how many of you wanted to build your own car? At least once in a life time, a passionate mechanical engineer thinks about this possibility. This is one of the most interesting subjects for any mechanical engineer. Here we learn some practical knowledge about how does engine really works. How does fuel is burnt in combustion chamber to produce tremendous power which propels automobile and make the world move at its own speed. we learn about how automobile bodies, transmission drives, cabin arrangement, exhaust gas handling systems are designed differently for differnt automobiles as per their applications and utility. It also introduces us the recent trends in the market and new technologies that will be coming in soon, which will change the future of automobile sector globally.

• Material science:

Any mechanical engineer is handicap without sufficient knowledge of material science. Material science deals with the micro structure, material properties, modes of failure, heat treatments, hardening, alloys, powder metallurgy, etc.

• Production engineering:

Here we learn about machines and technologies used for production of engineered products. This subject covers the theory of metal cutting, types of machining processes, calculation of time, cost, labor, equipment, forces induces for carrying out any production activity. We also learn some of the non conventional ways of machining which includes, electric discharge machining, chemical machining, water jet machining, ultra sonic, laser, abrasive machining.

• Manufacturing Technology:

This subject differs from production technology in a way that processes are carried out. In manufacturing technology to the maximum extend we used to do these processes without removing material from raw material and we do not use cutting tools to produce the finished good. This subject involves : casting techniques, forging, extrusion, rolling, wire drawing, sheet metal drawing, piercing, punching, welding, etc.

• Metrology and Quality control.

This is one of the essential streams in mechanical engineering for ensuring accuracy, precision and quality of the product . Quality is a relevant term in a sense, that it is relevant to your customer satisfaction and capability of maintaining the product quality at your end. In this subject we learn how to use measuring instruments, their types, least counts, measurement errors, standards of measuring instruments and units etc. Also we learn quality assurance tools and techniques.

• Industrial engineering and management:

It deals with the study of process optimization. For example if we are doing a process in certain way. Now we realize that we could do the process in better way; then we study the process, we find the scope for improvement and its techno commercial consequences and then implement the new process. Mostly we study machining time measurement, man hours, safety, measurement of  performance, scientific methods for carrying out work study  etc. From another perspective we also learn about game theory, inventory management, PERT, CPM techniques, etc. In management we learn about types of organizations, their hierarchy and structure, management styles, management principles, business ethics, hiring process for new employees, laws and rights of an employees etc. Apart from above you will also need to learn following skills to be a successful and full fledged engineer.

1. At least 1 CAD Sofware like: Inventor, Auto CAD, Solidworks, CATIA, CREO, Etc.
2. Matlab.
3. Coding softwares like C.C++, Python.
4. Any one structural analysis / CFD software like ANSYS, Comsol, Star CCM, etc.
5. MS Excel and MS Words. (You may think Everybody knows, but learn them properly).