A comprehensive guide "100 Writing Mistakes to Avoid" by Maeve Maddox

"100 Writing Mistakes to Avoid" by Maeve Maddox is a comprehensive guide aimed at helping writers enhance their craft by steering clear of common pitfalls. Maddox, a seasoned writer and language enthusiast, outlines various errors that writers often make and provides practical advice on how to rectify them. From grammatical blunders to stylistic faux pas, this book offers valuable insights to improve clarity, coherence, and overall effectiveness in writing. Whether you're a novice writer seeking to refine your skills or a seasoned wordsmith looking to polish your prose, "100 Writing Mistakes to Avoid" is an invaluable resource for honing your craft and elevating your writing to the next level.

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Air Fuel Ratio of Diesel Engine

     ____    _                        __           ___      ______  ____

    / __ \  (_) ___    _____  ___    / /          /   |    / ____/ / __ \

   / / / / / / / _ \  / ___/ / _ \  / /          / /| |   / /_    / /_/ /

  / /_/ / / / /  __/ (__  ) /  __/ / /          / ___ |  / __/   / _, _/

 /_____/ /_/  \___/ /____/  \___/ /_/          /_/  |_| /_/     /_/ |_|

                    __ __       ___  __ __        ______  ______

                 __/ // /_     <  / / // /       / ____/ / ____/

                /_  _  __/     / / / // /_      /___ \  /___ \

               /_  _  __/     / / /__  __/ _   ____/ / ____/ /

                /_//_/       /_/    /_/   (_) /_____/ /_____/

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Let's take a look at your figures.

With a diesel fuel oil consisting of 86.5% C, 13.2% H, 0.3% S and 0%O

86.5/12=7.21 where 12 is the molecular weight of carbon.

So ignoring the 0.3% sulphur, we can pretend your hydrocarbon is C7.21H13.2. (I'm not saying the molecules are that short, I'm just thinking about the carbon hydrogen ratio.)

CxHy + a(O2+0.79/0.21N2) => xCO2 + y/2H2O + a*0.79/0.21N2
where a=x+y/4

in this case, a= 7.21 + 13.2/4 = 10.51

AFR = a(MWO2+0.79/0.21*MWN2)/MWfuel
AFR = 10.51 (32 + 28*0.79/0.21) / (86.5+13.2)
    = 10.51 * 137.33 / 99.7
    = 14.42

14.55 Kg air to Kg fuel
So a rough calculation for your fuel (ignoring the sulpher in the fuel, argon in the air, etc) gives 14.42 which is pretty close to the figure you gave - not that I ever doubted you, ..., more a question of trying to understand why things are the way they are.

So why the difference to the earlier estimate?

If hydrogens were about 2:1 with the carbons, we could expect an AFR a bit below 15 as indicated earlier.

7.21*2= 14.42.
The actual percentage hydrogen you give is 13.2, ie less that 2 hydrogens per carbon.

What is the difference between PT & CVT ? Why CVT is used in HT X-mission line in place of PT ?

PT (Planetary Transmission) and CVT (Continuously Variable Transmission) are two different types of transmission systems used in vehicles, each with its own set of characteristics and advantages.

1. Planetary Transmission (PT):

   • A PT, also known as an automatic transmission, consists of a set of gears, clutches, and planetary gear sets.
   • It operates by shifting between a finite number of discrete gear ratios (e.g., 1st gear, 2nd gear, etc.).
   • The gear changes are usually achieved by engaging or disengaging clutches and bands to connect different gear sets.
   • PTs are known for their smooth operation and are widely used in both automatic and semi-automatic transmission systems.
   • They are relatively simple in design and have been used for many years in various types of vehicles.

2. Continuously Variable Transmission (CVT):

   • A CVT is a type of automatic transmission that can seamlessly change through an infinite number of gear ratios within a specified range.
   • Instead of using fixed gears, CVTs use a system of belts, pulleys, or chains to vary the transmission ratio continuously.
   • This allows the engine to operate at its most efficient speed for a given driving condition, improving fuel efficiency and providing smoother acceleration.
   • CVTs are particularly advantageous in situations where a wide range of gear ratios is required, such as in vehicles with varying loads or driving conditions.

As for why CVT is used in certain high-torque (HT) transmission lines instead of PT, there are several reasons:

1. Efficiency: CVTs are often more efficient than traditional PTs, especially in transmitting high levels of torque without the need for multiple gear changes.

2. Smoothness: CVTs provide smoother acceleration and deceleration compared to PTs, which can be desirable in high-torque applications where jerkiness in gear changes may be more pronounced.

3. Adaptability: CVTs can continuously adjust their gear ratios to optimize engine performance under varying load and speed conditions, making them well-suited for high-torque applications where flexibility is essential.

4. Compactness: In some cases, CVTs can be more compact and lightweight than PTs, allowing for easier integration into vehicles with limited space or weight constraints.

Overall, the decision to use CVT instead of PT in high-torque transmission lines is typically based on the specific performance requirements, efficiency goals, and design considerations of the vehicle or machinery in question.

Four-Stroke Diesel Engine

A four-stroke diesel engine is an internal combustion engine that operates on the four-stroke cycle principle, also known as the Otto cycle. These engines are commonly used in a variety of applications, including automobiles, trucks, buses, ships, locomotives, and industrial equipment. Here's how a four-stroke diesel engine works:

1. Intake Stroke:

• During the intake stroke, the intake valve opens, and the piston moves downward, creating a vacuum in the cylinder.
• Air is drawn into the cylinder through the intake valve, filling the combustion chamber with fresh air.

2. Compression Stroke:

• Once the intake stroke is complete, the intake valve closes, and the piston begins to move upward, compressing the air within the cylinder.
• As the piston moves upward, the air is compressed, increasing its temperature and pressure. This compression raises the air temperature to the point where diesel fuel injected into the combustion chamber will ignite spontaneously.

3. Power Stroke:

• When the piston reaches the top of its stroke, diesel fuel is injected into the combustion chamber at high pressure by the fuel injector.
• The fuel mixes with the highly compressed air, and the heat of compression ignites the fuel spontaneously, causing it to combust rapidly.
• The combustion of the fuel-air mixture generates a high-pressure, high-temperature gas that exerts force on the piston, driving it downward. This is the power stroke, where the engine produces mechanical work.

4. Exhaust Stroke:

• After the power stroke, the exhaust valve opens, and the piston moves upward again, pushing the exhaust gases out of the cylinder.
• The expelled exhaust gases are routed through the exhaust system to the atmosphere, completing the four-stroke cycle.

Key Components of a Four-Stroke Diesel Engine:

1. Cylinder: The combustion chamber where the fuel-air mixture is ignited and the power stroke occurs.

2. Piston: Moves up and down within the cylinder to compress the air-fuel mixture, absorb the force of combustion, and expel exhaust gases during the exhaust stroke.

3. Crankshaft: Converts the linear motion of the piston into rotational motion, transferring power from the engine to the transmission and ultimately to the wheels or driven equipment.

4. Camshaft: Controls the opening and closing of the intake and exhaust valves, synchronizing their operation with the movement of the piston.

5. Fuel Injector: Delivers a precise amount of diesel fuel into the combustion chamber at the correct time and under high pressure, ensuring efficient combustion and power generation.

Four-stroke diesel engines are known for their durability, fuel efficiency, and torque output, making them suitable for heavy-duty applications and long-distance transportation. They are widely used in the automotive industry and various industrial sectors due to their reliability and versatility.

Cooled exhaust gas recirculation - Function and application

Cooled Exhaust Gas Recirculation (EGR) is an emission reduction technique used in internal combustion engines, particularly in automotive engines, to reduce nitrogen oxide (NOx) emissions by recirculating a portion of exhaust gases back into the engine's combustion chambers. The recirculated exhaust gases, which are cooler than the intake air, help lower the combustion temperatures and reduce the formation of NOx pollutants.

Function:

1. NOx Reduction: The primary function of cooled EGR is to reduce nitrogen oxide (NOx) emissions by diluting the fresh air-fuel mixture in the combustion chamber with inert exhaust gases. By lowering the combustion temperature, cooled EGR helps reduce the formation of NOx, which is a harmful pollutant contributing to air pollution and smog.

2. Combustion Control: Cooled EGR allows for more precise control of combustion conditions by adjusting the amount of recirculated exhaust gases based on engine operating parameters such as load, speed, and temperature. This control strategy helps optimize fuel efficiency and emissions performance under varying operating conditions.

3. Detonation Prevention: Cooled EGR can also help prevent engine knock or detonation by reducing the peak combustion temperatures and pressures inside the cylinders. This is particularly important in gasoline engines with turbocharging or high compression ratios, where detonation can lead to engine damage and reduced performance.

Application:

Cooled EGR is widely used in various types of internal combustion engines, including:

1. Automotive Engines: Cooled EGR systems are commonly used in modern gasoline and diesel engines to meet stringent emissions regulations, such as Euro 6 standards in Europe and Tier 3/4 standards in the United States. Automotive manufacturers employ cooled EGR in combination with other emissions control technologies, such as selective catalytic reduction (SCR) and diesel particulate filters (DPF), to achieve compliance with emissions limits.

2. Commercial Vehicles: Cooled EGR systems are also used in heavy-duty diesel engines for trucks, buses, and off-road vehicles to reduce NOx emissions and improve air quality. These engines often incorporate advanced exhaust aftertreatment systems, such as diesel oxidation catalysts (DOCs) and diesel particulate filters (DPFs), to further reduce emissions.

3. Marine and Industrial Engines: Cooled EGR technology is applied in marine engines, stationary power generators, and industrial equipment to minimize NOx emissions and comply with environmental regulations. These engines may use a combination of EGR, selective catalytic reduction (SCR), and exhaust gas treatment systems to meet emissions standards while maintaining optimal performance and reliability.

Overall, cooled exhaust gas recirculation (EGR) is a key emissions control technology used in internal combustion engines to reduce nitrogen oxide (NOx) emissions, improve fuel efficiency, and meet regulatory requirements for clean air and environmental protection. As emissions standards continue to evolve, the development and implementation of advanced EGR systems play a crucial role in reducing the environmental impact of transportation and industrial activities.

Introduction to Gas Turbines and Applications

Gas turbines, also known as combustion turbines, are versatile engines used for a variety of applications, ranging from power generation and propulsion to industrial processes and mechanical drive systems. These turbines operate on the principle of converting the energy of fuel combustion into mechanical energy through the rotation of a shaft.

Here's an introduction to gas turbines and their applications:

Basic Components of a Gas Turbine:

1. Compressor: The compressor section of a gas turbine compresses incoming air to high pressure before it enters the combustion chamber. Compressing the air increases its temperature and pressure, which enhances the efficiency of the combustion process.

2. Combustion Chamber: In the combustion chamber, fuel is injected and mixed with compressed air. The fuel-air mixture is then ignited, leading to rapid combustion and the generation of high-temperature, high-pressure gases.

3. Turbine: The high-temperature, high-pressure gases produced in the combustion chamber expand through the turbine section, driving the turbine blades and causing the turbine shaft to rotate. This rotational motion is used to power an electric generator, drive a mechanical load, or propel an aircraft.

4. Exhaust System: After passing through the turbine section, the exhaust gases exit the gas turbine through the exhaust system. In some applications, the exhaust gases may be used to generate additional power through a heat recovery system or to provide thrust in jet propulsion systems.

Applications of Gas Turbines:

1. Power Generation: Gas turbines are widely used for electricity generation in both central power plants and distributed power generation facilities. They are often used in combined cycle power plants, where the exhaust gases from the gas turbine are used to generate steam in a heat recovery steam generator (HRSG) to drive a steam turbine and produce additional electricity.

2. Aircraft Propulsion: Gas turbines, particularly turbojet and turbofan engines, are used to propel aircraft. These engines provide high thrust-to-weight ratios and are capable of operating at high altitudes and speeds. Turbofans, in particular, are commonly used in commercial airliners due to their fuel efficiency and quiet operation.

3. Marine Propulsion: Gas turbines are used to power various types of ships and naval vessels, including cruise ships, ferries, and military vessels. Gas turbine propulsion systems offer advantages such as high power density, rapid response times, and reduced emissions compared to traditional steam turbine systems.

4. Industrial Applications: Gas turbines are used in a wide range of industrial applications, including mechanical drive systems for pumps, compressors, and generators. They are also used in the oil and gas industry for natural gas compression and processing, as well as in chemical plants, refineries, and other manufacturing facilities.

5. Cogeneration and Combined Heat and Power (CHP): Gas turbines are often used in cogeneration and CHP systems to simultaneously generate electricity and heat for industrial processes, district heating, or commercial buildings. This integrated approach improves overall energy efficiency and reduces greenhouse gas emissions.

Gas turbines offer a flexible and efficient means of power generation and propulsion, with applications spanning various industries and sectors. Advancements in gas turbine technology continue to drive improvements in efficiency, reliability, and environmental performance, making them a vital component of modern energy systems and transportation networks.