Portal field news

Portal field news

in ,

🚗 | Automotive product attractiveness, Lexus is the overall top ... JD power by brand


Photo 2021 Japan Automobile Product Attractiveness Survey Brand Ranking

Lexus is the top overall in terms of attractiveness of automobile products ... JD power by brand

 
If you write the contents roughly
On the other hand, regarding the "fuel efficiency / cruising range" evaluation, electric vehicles had the lowest score of 579 points, and there were still issues.
 

On October 10, JD Power Japan announced the results of the 13 Japan Automobile Product Attractiveness (APEAL) Survey. … → Continue reading

 response


Wikipedia related words

If there is no explanation, there is no corresponding item on Wikipedia.

Cruising distance

Cruising distanceWhat is (Kozo Kyori)?aircraft,Ship,Electric carEtc. are the maximum distances that can be loaded with fuel up to the maximum load capacity, or can be navigated and operated.Originally used in the fields of ships and aviation, the term began to be used in automobiles in the latter half of the 1990s as the development of electric vehicles progressed, and around 2010, the distance that electric vehicles can run on a single charge. It became an indispensable term to describe.Also, not limited to automobiles, etc.Electric scooter,Electric kick boardMay be used for vehicles that run on fuel or electricity such as[1].

aircraft

Cruising range is maximum flight time to ground speed tMax Is multiplied by. The formula for calculating the cruising range for propeller aircraft and jet aircraft is shown below.

Derivation

How much fuel is consumed in a unit time (fuel consumption rate) is first calculated by the following formula:

Burned fuel (dWf) The weight of the aircraft will be lighter (-dW), so dWf = -dW. Therefore

The amount of change in the amount of fuel loaded per unit distance is calculated by the following formula. However,VIs speed:

Then the cruising range is calculated by the following definite integral:

Here, V / F is called the cruising rate and represents the flight distance per unit fuel weight. Here, the cruising rate is calculated on the assumption that the aircraft is flying almost stably. The next section describes the differences between jets and propeller propulsion aircraft.

Propeller plane

Equilibrium conditions for propeller aircraft Pa = Pr Therefore, it is necessary to find the speed of level flight at a certain aircraft weight. Propulsion efficiency ηj And fuel consumption rate cp Are each a function of flight speed. The engine output is calculated by the following formula:

Then find the corresponding fuel weight flow rate:

The output (power) required for propulsion is the speed at which drag is applied, and drag is calculated from the lift-drag ratio. Lift because it is level flight L = Weight W Note that

Assuming that the lift-drag ratio is constant, the cumulative cruising range is:

To obtain an analytical representation of range, it should be noted that cruising rate and fuel weight flow depend on the aircraft and propulsion system, but assuming they are constant:

Jet

Similarly, the calculation of a jet aircraft is performed by the following method. Here, we assume a nearly stable level flight. Use the relationship of the following equation.

Thrust can be written as:

Jet engines are characterized by thrust relative to fuel consumption. That is, fuel consumption is proportional to drag, not engine output.

Using the lift formula,

Where ρ is the air density and S is the wing area.

The cruising rate is equal to:

Finally, the cruising range is required:

When cruising at a constant altitude, a constant angle of attack, and a constant fuel consumption rate, the cruising range is:

However, the compression ratio due to the aerodynamic characteristics of the aircraft is ignored.

Calculated by Mach number

In long-range jet flights in the stratosphere, the speed of sound is constant, so when flying at a constant Mach number, the aircraft rises without changing the local speed of sound. in this case,

However, M is the cruising Mach number and a is the speed of sound. The cruising range equation can be transformed as follows:

Or,

Ship

Since the ship has a relatively large hull compared to other means of transportation, it is possible to load a large amount of fuel in a large tank. Also, if you sail at low speed, fuel efficiency will improve, so the cruising range is long.tankerEtc. can sail for two months without replenishment for a distance that goes around the earth halfway[2]..In recent years, tankers have become larger, and super-large tankers with a cruising range of over 40,000 km (equivalent to one round of the earth) are also commissioned.[3][4].

Cruising distance

The longest distance that can be sailed without refueling is called the "cruising distance".A large fuel tank is equipped with an engine with a good fuel consumption rate and an efficient propulsion device, and if a ship with low hull resistance runs at a low speed, the cruising range will increase, but when calculating the cruising range, use the distance at normal output. .. The daily fuel consumption per 1 horsepower is about 1 tons for a diesel engine and about 30 tons for a steam turbine.Except for warships that consume a lot of fuel, it is the container ships and ferries that sail at high speed that consume a lot of fuel for their size.

In particular,

  • 20 deadweight tonnage oil / crude oil tanker: 150 nm with consumption of about 17,000 tons
  • 6 deadweight tonnage (barazumisen): 50-15,000 nm with consumption of about 25,000 tons
  • 2 deadweight tonnage cargo ship: Approximately 30 nm with a consumption of 15,000 tons
  • 1,000 nm on a 20,000 ton fishing boat

It will be such a place.

Related item

footnote

  1. ^ Hajime Kobayashi (August 2021, 8). “Read the news New Yojijukugo Dictionary 24th [Cruising Range] Kozo Kyori". Sanseido Language Column.Sanseido. NovemberBrowse.
  2. ^ Supervised by Yoshiho Ikeda "Book that understands everything about ships" Natsumesha, published on February 2009, 2 ISBN 9784816346408
  3. ^ Kawasaki Heavy Industries Press Release [Broken link]
  4. ^ Introducing our own vessel by Idemitsu tanker

 

Back to Top
Close