Pressurization rate vs. Mass Flow rate

Click For Summary

Discussion Overview

The discussion revolves around the relationship between pressurization rate and mass flow rate in the context of a valve's flow rate requirements. Participants explore the implications of working with adiabatic systems as opposed to isothermal conditions, and the challenges of converting mass flow rate measurements to pressure flow rate metrics.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Conceptual clarification

Main Points Raised

  • One participant is attempting to relate mass flow rate (lbm/s) to pressure flow rate (psi/s) due to customer requirements, noting the complexity introduced by adiabatic conditions.
  • Another participant questions the definition of "pressure flow rate" and suggests there may be a misunderstanding or miscommunication from the client.
  • A follow-up response clarifies that the client's design does not currently allow for mass flow rate measurement, hence the request for a pressurization rate.
  • Another participant asks for additional context, specifically whether the tank is positioned before or after the valve, indicating a need for more information to understand the scenario better.

Areas of Agreement / Disagreement

Participants express uncertainty regarding the client's request for a pressure flow rate and whether it is a valid or misquoted term. There is no consensus on the best approach to relate the two flow rates, and the discussion remains unresolved.

Contextual Notes

The discussion highlights the dependence on specific system conditions (adiabatic vs. isothermal) and the potential limitations in the client's design that affect measurement capabilities.

Kerky
Messages
2
Reaction score
0
Good afternoon all,

I am doing some back of napkin calcs for work and am having trouble finding an answer (or one that I can understand--its been a while since undergrad). We have a valve that has particular flow rate requirements to prevent unseating the valve seal. This is a mass flow rate and our customer has requested a pressure flow rate (so instead of lbm/s, they want psi/s). I can do it for a simple isothermal system using the ideal gas law, but our tanks are adiabatic.

I have found various explanations, like a ratio of pressures = ratio of densities to some function of gamma, and a dimensionless form of the pressure/time for choked mass flow rate.

If anybody can ELI5 or give me some guidance I would be very appreciative.
 
Science news on Phys.org
Kerky said:
pressure flow rate
What is that?
Is the client being mis-quoted?
 
256bits said:
What is that?
Is the client being mis-quoted?
No, but their current design does not allow them to measure mass flow rate so they requested a pressurization rate.
 
Is the tank before or after the valve? Can you provide a diagram? It's very hard to read your mind?
 

Similar threads

Graduate Mass flow rate for compressible flow
  • · Replies 2 ·
Replies
2
Views
5K
Graduate Final pressure and temperature knowing only air mass outflow
  • · Replies 3 ·
Replies
3
Views
2K
Undergrad Energy needed for achieving this mass flow rate for a rocket
  • · Replies 24 ·
Replies
24
Views
3K
Undergrad Given a fixed volume of pressurized air, calculate the flow rate
  • · Replies 3 ·
Replies
3
Views
3K
Flow rate of air through constriction
  • · Replies 10 ·
Replies
10
Views
4K
Graduate Water flow from pressurized tank - versus temperature
  • · Replies 5 ·
Replies
5
Views
3K
Graduate Adiabatic Compressible Flow in a Converging Duct
  • · Replies 6 ·
Replies
6
Views
2K
Undergrad How Does Valve Opening Affect Flow Rate from a Pressurized Tank?
  • · Replies 1 ·
Replies
1
Views
2K
Good valve for really small flow rates?
  • · Replies 10 ·
Replies
10
Views
2K
Undergrad Flow rate calculation of coating application
  • · Replies 30 ·
2
Replies
30
Views
3K