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Working volume · return flow · time

Hydraulic reservoir dwell time

Inputs

User-entered liquid working volume; tank geometry, fluid level, and total vessel capacity are not derived.
User-entered steady flow used only for literal volume-over-flow dwell arithmetic.
User-entered time reference for a literal equivalent-volume comparison; it is not a requirement or recommendation.

Results

Literal reservoir dwell timet

5

Literal volume at declared dwell-time reference

120

Literal dwell-time / reference ratio

1.25

1
Declared return or pump flowQ

30

tdwell = Vworking/Qreturn; Vref = Qreturn·tref; ratio = tdwell/tref

A first-pass number, not a code check, certification, or approval. Read the method and its limits below. What this is and is not.

Nearby: Hydrostatic pressure · Flow continuity · Pipe mean velocity · Bernoulli equation

Method

Formula, when it applies, and when it does not

Convert working reservoir volume and return flow into dwell time and a user-reference-volume comparison without sizing a reservoir or evaluating thermal performance.

tdwell = Vworking/Qreturn; Vref = Qreturn·tref; ratio = tdwell/tref

When

  • Declared pump or return flow
  • Steady volume-over-flow dwell relation
  • User-entered dwell-time reference

Don’t

  • This divides only a declared working reservoir volume by a declared steady flow, then compares that result to a user-entered reference time. It does not select a reservoir, apply a rule-of-thumb, estimate cooling, aeration, contamination, geometry, fluid level, heat rejection, flow distribution, capacity, safety, suitability, or approval.
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