DEPARTMENT OF MECHANICAL ENGINEERING

  Working Principles of Combustion Engine 1. Introduction A combustion engine , commonly called an Internal Combustion Engine (IC Engine) , is a heat engine in which the combustion of fuel takes place inside the engine cylinder . The chemical energy of the fuel is converted into: Chemical Energy → Heat Energy → Pressure Energy → Mechanical Energy → Rotary Motion IC engines are widely used in automobiles, motorcycles, tractors, generators, construction equipment, ships and many industrial applications. 4 2. Basic Principle of an IC Engine The basic working principle is based on the burning of fuel inside a cylinder . When fuel burns with air, a large amount of heat is released. This produces high-pressure gases , which act on the piston. The piston moves up and down inside the cylinder. This reciprocating motion is converted into rotary motion by the: Piston → Connecting Rod → Crankshaft The crankshaft then supplies useful mechanical power to the vehicle or machine. Energy Conversio...

 Recent/new automobile engine technologies Turbocharged downsized petrol engines — smaller engines with turbochargers produce power comparable to larger engines while improving efficiency. Hybrid engines — petrol engines work with electric motors; common systems include series-parallel hybrids and plug-in hybrids (PHEVs) . Mild-hybrid systems (48V) — an electric motor assists the engine during acceleration and enables regenerative braking and start-stop operation. Variable compression ratio engines — the engine changes its compression ratio depending on driving conditions to balance power and fuel economy. Atkinson/Miller-cycle engines — increasingly used in hybrids because they prioritize thermal efficiency. Direct-injection petrol engines — fuel is injected directly into the combustion chamber for better control and efficiency. Advanced diesel engines — modern diesels use technologies such as common-rail injection, turbocharging, EGR, diesel particulate filters, an...

  The Seven Quality Control Tools (Q7 Tools) Quality control isn't magic — it's method. Long before Six Sigma and modern quality software existed, engineers and quality professionals in Japan compiled seven simple, visual, statistical tools that anyone on a shop floor could learn and apply without a statistics degree. Kaoru Ishikawa popularized this toolkit, and it became known as the Seven QC Tools (Q7 Tools) . These tools remain the backbone of quality management systems (ISO 9001, Six Sigma, Lean, TQM) because they turn raw data into decisions. This guide walks through each tool's construction, types, uses, and limitations. 1. Check Sheet A check sheet is a simple, structured, pre-designed form used to collect and record data in real time at the location where it's generated. It converts raw observations into countable, organized facts. Construction Define the purpose — what question needs answering (defect type, location, time of occurrence). Decide what da...

  Latest Trends in Press Working  Press working (sheet metal working) is advancing through automation, precision control, and digital manufacturing. The latest developments include: 1. Servo Press Technology Uses servo motors instead of conventional flywheel drives. Provides precise control of ram speed, position, and force. Advantages: Higher accuracy Better surface finish Longer die life Up to 30% lower energy consumption in suitable applications. 2. AI-Based Smart Presses Artificial intelligence monitors: Press load Die wear Sheet alignment Product quality Detects defects early and optimizes production automatically. 3. Industry 4.0 and IoT Integration Modern press shops use: Real-time sensors Cloud monitoring Predictive maintenance Digital production dashboards Automatic quality inspection. 4. High-Speed Progressive Die Stamping Multiple operations (piercing, bending, blanking, forming) are completed in one die set...

  Intelligent (AI-Driven) Forging Artificial intelligence monitors forging parameters in real time. Machine learning predicts defects, grain size, and mechanical properties. Adaptive process control automatically adjusts temperature, press force, and deformation. 2. Digital Twin Technology A digital replica of the forging line simulates the process before production. Enables: Real-time quality prediction Reduced trial-and-error Predictive maintenance Improved dimensional accuracy 3. Isothermal Forging Dies and workpiece are maintained at nearly the same high temperature. Used for: Titanium alloys Nickel superalloys Aerospace engine components Produces excellent dimensional accuracy with minimal defects. 4. Precision and Near-Net Shape Forging Components are forged close to their final dimensions. Benefits: Less machining Lower material waste Reduced manufacturing cost Higher productivity 5. Radial Forging with Precisio...