Partial charge with an alternator ???

[chatelot16]

very good note: mounted as a fixed telma does not ventilate enough it breathes its already hot air: in a truck which advances the air circulates better

but I have heard truck drivers talking about telma telma which heats up so much that it gets to the point of curia and lose all efficiency: it does not burn out because the part which heats is only cast iron

when it comes to wanting to lose the power of an engine we can put a big fan in addition

the classic method for large engine test stands is a centrifugal water pump

[bolt]

hello flytox

For the absorbed power it works as a cube of speed.

it wouldn’t be more like the square of the speed

bolt

[Flytox]

Hello Bolt

For the absorbed power it works as a cube of speed.

it wouldn’t be more like the square of the speed

bolt

From what I found in my archives:
From the book "The preparation of the engines" by Luc Méloua:



Next page



or from the internet:

http://clayesduciel.free.fr/electrique/volelec1.htm



I suppose that these different formulas are applicable, but there are ingenes on the forum who will be able to make the nuances that go well if necessary ....
A+

[bolt]

hello flytox

You are right about the "cubic"

it’s like calculating the power of wind turbines, also proportional to the cube of wind speed

if I understood the explanation correctly:

we are dealing with the kinetic energy of the mass of the wind in the case of the wind turbine (or rather the inertia of the mass of the ambient air in the case of the vehicle)

E = 1/2 M V²

and to deal with power (work per unit of time), we are therefore confronted with this mass per unit of time, that is

P = 1/2 (mass per second) V²

or, this mass / second = specific weight x flow

the flow being a volume per unit of time

either an area x length / unit of time

and length / unit of time = speed

we have well

P = specific weight of air x surface concerned x V x V²


bolt