What happens during the compression stroke?


What happens during the compression stroke?

Compression stroke: at the end of the intake stroke, both inlet and exhaust valves are closed. The inertial action of the crankshaft in turn lifts the piston which compresses the mixture. The ratio of the combustion chamber volume before and after compression is called the compression ratio.

Which cycle is more efficient?

Explanation: Otto cycle is more efficient than Diesel cycle for a given compression ratio. 6. For constant maximum pressure and heat input, the air standard efficiency of the gas power cycle is in the order.

What is the most efficient thermodynamic cycle?

The most efficient heat engine cycle is the Carnot cycle, consisting of two isothermal processes and two adiabatic processes. The Carnot cycle can be thought of as the most efficient heat engine cycle allowed by physical laws.

What is the efficiency of Otto cycle?

Efficiency is the proportion of the work and the supplied heat. For a cyclic process, the change in the total internal energy of the gas during one cycle is zero.

What is the cut off ratio?

The cutoff ratio is the ratio of the volume after combustion to the volume before combustion. ... However, practical Diesel engines uses higher compression ratios compared to petrol engines and are often quite efficient.

What is a good compression ratio?

Compression ratios usually range from 8:1 to 10:1. A higher compression ratio -- say, from 12:1 to 14:1 -- means higher combustion efficiency.

What is swept volume?

Swept volume can be defined as the volume swept by the engine piston during one stroke. Swept volume is also the product of piston area and stroke. 2. Clearance Volume. Clearance volume can be defined as the volume that remains in the cylinder when the engine piston is in the top centre position.

What is reciprocal of cut off ratio?

Mechanical Engineering :: Steam Boilers and Engines The cut-off ratio is the reciprocal of expansion ratio, ... The damper in a steam boiler is provided to control the draught (i.e. rate of flow of air) and thus regulate the rate of generation of steam.

What is the cut off ratio in thermodynamics?

Cut-off ratio is defined as the ratio of combustion chamber volume at the end of fuel injection/combustion and the combustion chamber volume at the beginning of fuel injection/combustion.

Which engine produces more power?

Cars with diesel engines generally struggle to compete with their gasoline-powered counterparts, which have higher horsepower and accelerate faster. But diesel engines produce way more torque.

What is not a part of diesel engine?

Which of the following is not a part of the diesel engine power station: Fuel tank. Lubrication system. Air intake.

What are the four strokes of a diesel engine?

A four-stroke diesel engine resembles a gasoline engine as it works on the four-stroke cycle, that is: admission, compression, power and exhaust.

Why diesel engine has more compression ratio?

Diesel engines use higher compression ratios than petrol engines, because the lack of a spark plug means that the compression ratio must increase the temperature of the air in the cylinder sufficiently to ignite the diesel using compression ignition.

What is scavenging air?

In automotive usage, scavenging is the process of pushing exhausted gas-charge out of the cylinder and drawing in a fresh draught of air or fuel/air mixture for the next cycle. This process is essential in having a smooth-running internal combustion engine.

What are the types of scavenging?

Abstract: The process of simultaneously purging exhaust gas and filling the cylinder with fresh charge for a new cycle is referred to as scavenging. The main scavenging methods are cross scavenging, loop scavenging and uniflow scavenging.

What are the three types of scavenging systems?

Three basic systems are in use: the cross flow, the loop and the uniflow. All modern slow-speed diesel engines now use the uniflow scavenging system with a cylinder-head exhaust valve.

How scavenging is done?

Scavenging is the process of replacing the exhaust gas in a cylinder of an internal combustion engine with the fresh air/fuel mixture (or fresh air, in the case of direct-injection engines) for the next cycle.

What is scavenging effect?

Scavenging also has a "mini supercharging effect". It speeds up the incoming air. This draws more fresh air into the cylinder. More clean air in the cylinder, mixed with the right amount of fuel, and proper Ignition Timing, means more Torque and Horsepower! Scavenging is a delicate process to control inside the engine.

Why scavenging is required?

Scavenging is the process of removing exhaust gases from the cylinder after combustion and replenishing the cylinder with fresh air. Efficient scavenging is necessary for good combustion of fuel inside the engine cylinder. The passage of scavenge air will also assist cooling of the cylinder, piston and valves.

What does Scavange mean?

1a(1) : to remove (dirt, refuse, etc.) from an area. (2) : to clean away dirt or refuse from : cleanse scavenge a street. b : to feed on (carrion or refuse)4 dagen geleden

What does superficial mean in English?

superficial, shallow, cursory mean lacking in depth or solidity. superficial implies a concern only with surface aspects or obvious features. a superficial analysis of the problem shallow is more generally derogatory in implying lack of depth in knowledge, reasoning, emotions, or character.

What does prodding mean?

verb prods, prodding or prodded to poke or jab with or as if with a pointed object. (tr) to rouse or urge to action.

What does predatory mean?

1a : of, relating to, or practicing plunder, pillage, or rapine. b : inclined or intended to injure or exploit others for personal gain or profit predatory pricing practices. 2 : living by predation : predaceous also : adapted to predation.

What are the 4 types of predators?

There are four major types of predation:

  • Carnivory. Carnivorous predators kill and eat their prey. ...
  • Herbivory. Herbivorous predation involves the consumption of autotrophs, such as plants or photosynthetic algae. ...
  • Parasitism. ...
  • Mutualism. ...
  • Carnivorous Predation. ...
  • Herbivorous Predation. ...
  • Parasitic Predation. ...
  • Mutualism.

What is predatory behavior?

Predatory behavior is one of the unhealthy toxic behavior patterns that a person might encounter in their life. A predator can be anyone around you from a colleague, to a family member, friend, or a romantic partner.

Do humans have a natural predator?

The only documented man-eaters among the great apes are humans themselves and chimpanzees. As humans encroach further on chimpanzee habitat in Africa, the occurrence of chimpanzees killing human children has allegedly become more common.

Can a tiger eat human bones?

2. A tiger can digest bones from the human body. According to Joe Exotic.

What animal kills the most humans per year?

Mosquitoes

Стоит почитать

Похожие вопросы