QuickField

A new approach to field modelling

Main >> Applications >> Sample problems

Mutual capacitance of collinear cylinders

mutual capacitance calculation, collinear cylinders capacitance

Find the mutual capacitance between two collinear infinitely long cylinders.

Problem Type:
Plane-parallel problem of electrostatics.

Geometry:
Cylindrical capacitor Capacitor consists of two coaxial cylindrical collinear electrodes -q +q a b l = 1000 mm

a = 5 mm, b = 10 mm.

Given:
Relative permittivity of air ε = 1,
The charge q = 1 nC.

Task:
Find the mutual capacitance between two collinear infinitely long cylinders and compare it with analytical solution: C = 2πεε0 * l / ln(a/b) [F]. *

Solution:
Each of the conductor's surface is marked as 'floating conductor', i.e. isolated conductors with unknown potential. At some point on each of conductor's surface the charge is applied. The charge is then redistributed along the conductor surface automatically.

Results:
Potential distribution between collinear cylinders.

collinear cylinders voltage distribution

The capacitance can be calculated as C = q / (U2 - U1). The measured potential difference is U2-U1 = 12.459 V.
The capacitance is C = 10-9 / 12.459 = 8.027·10-11 F.

QuickField Theoretical result
C, pF
(model depth l = 1 m)
80.27 80.26

*Wikipedia, Capacitance.

  • Video: Mutual capacitance of collinear cylinders
  • View simulation report in PDF
  • Download simulation files (files may be viewed using any QuickField Edition).
  • New version QuickField 6.5

    Product
    Order
    Evaluation request
    Editions
    Version history
    Packages
    Components
    Programming
    Consulting

    Applications
    Industrial
    Educational
    Scientific
    Sample problems
    Success stories
    Customers

    Support
    Webinars
    Virtual Classroom
    Online courses
    Customer login
    Glossary
    QuickField help
    FAQ

    Downloads
    QuickField Student Edition
    User manual
    Data Libraries
    Video
    Free tools

    News
    Product News
    Events
    Publications
    Subscription

    Contacts
    Tera Analysis info
    Resellers
    Contact us
    Online chat
    About us