Fly Lah!

Hi guys..

Well I get stuck with the terms of UPSTREAM and DOWNSTREAM.

ex: In a fuel system, HP side is on an engine and LP is outside the engine.

which one is correct?

1) The HP side is located upstream of LP side. (this one i look on the pressure. the high pressure is upstream.the fuel tank is in LP so it is downstream.)

2) THe HP side is located downstream of LP side. (this one i refer to- from where the fuel comes. the start is fuel tank.)

Is Upstream refer to high pressure or low pressure?

or

Is Upstream refer to a high point (or starting point) and Downstream refer to the next point?



Do you know what i mean? don't laugh because sometimes the easy tends to confuse.

a layman's explanation for upstream is going into the system whilst downstream is leaving the system back to its reservoir/tank etc etc....

Quite.
It is the location of the component with respect of the system fluid flow/pressure. IF that component is to receive the fluid/pressure earlier than the reference part/component, it is said to be located in the 'upstream' and vice-versa..

okay...for a basic hydraulic system, a filter is installed after a pump - means that it is the pump first, right?

so the pump is located upstream of the filter?

it is similar to a stream of a river where the starting is called upstream?


correct me for any mistake.


it is rather confuse because a hydraulic system which have a return line is different from a river.

but for a brake hydraulic system that uses single acting actuator is easy to understand due to no return line. (like a river)

Pressure,return, breather lines or whatever. No confusion as its all reference to the flow.. nothing to it.
Too complex for you to grasp huh?

Hi there, from what I've learned so far, what torx said is right. For example, in a hydraulic system, a filter is installed after the pump. So, we can say that the filter is fitted DOWNSTREAM of the pump. Just follow the flow direction from the reservoir to the end ,e.g actuator . Hope it helps

Correct! and the pump is UPSTREAM of the filter!

just got confuse somehow... damn!!


it is the flow. yes, thanks..

LOL