Pressure vs. neck shortening of a balloon

  • Thread starter Thread starter dislect
  • Start date Start date
  • Tags Tags
    Balloon Pressure
Click For Summary

Discussion Overview

The discussion revolves around the relationship between pressure and the shortening of the cervix, using a balloon as an analogy for the human womb. Participants explore the theoretical framework for modeling this phenomenon, including the relevant equations and material properties involved.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant proposes developing equations to connect cervix length, overall thickness, womb radius, and material properties, assuming constant thickness and material properties.
  • Another participant questions the clarity of the analogy between a balloon and the human womb, indicating confusion about the subject matter.
  • A subsequent reply clarifies that the balloon serves as an analogy for the human womb, suggesting a focus on balloons for the discussion.
  • Some participants express skepticism about the similarity between the two concepts, indicating a lack of consensus on the analogy's validity.

Areas of Agreement / Disagreement

Participants do not appear to agree on the appropriateness of the balloon analogy for discussing the human womb, leading to confusion and differing interpretations of the topic.

Contextual Notes

The discussion lacks clarity on the assumptions regarding the material properties and the specific equations needed to model the relationship between pressure and cervix shortening.

dislect
Messages
163
Reaction score
0
Pressure vs. "neck" shortening of a balloon

I swear this is not a homework question :approve:

The purpose of this question is to simulate the shortening of the cervix ("neck") as a result of the increase of pressure -> volume of the female womb.

I would like to come up with a set of equations connecting between the:
1. cervix ("neck") length - shown as 40mm and 25mm in pics
2. overall thickness - shown as 15mm in pics
3. womb radius - shown as 100mm and 105mm in pics (random approximate numbers)
4. material properties (young's modulus, yield strength, density if relevant)

We can assume the:
a. Thickness stays approximately constant
b. material properties stays constant

So in theory I would be able to input the pressure inside the balloon and receive the cervix "neck" new length (shortening) as a result of the balloon inflating and taking away from that neck's length.

I would love someone to guide me and send me the right way. I can't really use laplace's/pascal law because the thickness is not negligible.

Thanks a lot!

Pics for demonstration

image.jpg

image.jpg

laplaceslaw.jpg
 
Engineering news on Phys.org
Are we talking about people or balloons? Your post is confusing.
 
SteamKing said:
Are we talking about people or balloons? Your post is confusing.

Balloon is the analogy simplification of the human womb.
Let's stick with balloons.
 
Sorry, don't see the similarity.
 
http://www.shinesa.org.au/images/dmImage/SourceImage/Stages-of-pregancy.gif
 
Last edited by a moderator:

Similar threads

Graduate Balloon change of thickness, diameter and pressure
  • · Replies 6 ·
Replies
6
Views
8K
Mechanical modeling of inflating a elastomeric balloon
  • · Replies 6 ·
Replies
6
Views
2K
Surface roughness in 2D sinusoidal corrugation
  • · Replies 1 ·
Replies
1
Views
5K
Electromagnetics: Non-Symetrical coil with external iron
  • · Replies 4 ·
Replies
4
Views
3K