Model number

The model simulates current flow through a capacitor C and is the electrical analog of fluid flowing into or out of a compliant vessel with no outlet.


This model is the electrical analog of fluid flowing into or out of a compliant vessel with no outlet. The current, IC, flowing into or out of the capacitor is given by the change in the input voltage with respect to time, dVi/dt , multiplied by the capacitance, C. When the voltage is not changing, the current is zero and the capacitor is fully charged. The fluid analogs for voltage (volts), current (coulombs/sec) and capacitance (farads) are pressure (mmHg), flowrate ( mL/sec) and compliance (mL/mmHg). Note in the fluid analog that change in pressure is equivalent to the change in volume divided by the compliance, C.


The equations for this model may be viewed by running the JSim model applet and clicking on the Source tab at the bottom left of JSim's Run Time graphical user interface. The equations are written in JSim's Mathematical Modeling Language (MML). See the Introduction to MML and the MML Reference Manual. Additional documentation for MML can be found by using the search option at the Physiome home page.

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Nilsson JW and Riedel SA: Electric Circuits. Upper Saddle River, New Jersey, Prentice Hall, 2001, 1018 pp. REVISION HISTORY: Original Author : JBB Date: 06/12/08 Revised by: Micah Nicholson Date: 4/2/2009 Revision: 1) Update format Revised by : BEJ Date: 21/Apr/10 Revision: 1) Correct format

Key terms
no outlet
RC circuit

Please cite in any publication for which this software is used and send one reprint to the address given below:
The National Simulation Resource, Director J. B. Bassingthwaighte, Department of Bioengineering, University of Washington, Seattle WA 98195-5061.

Model development and archiving support at provided by the following grants: NIH U01HL122199 Analyzing the Cardiac Power Grid, 09/15/2015 - 05/31/2020, NIH/NIBIB BE08407 Software Integration, JSim and SBW 6/1/09-5/31/13; NIH/NHLBI T15 HL88516-01 Modeling for Heart, Lung and Blood: From Cell to Organ, 4/1/07-3/31/11; NSF BES-0506477 Adaptive Multi-Scale Model Simulation, 8/15/05-7/31/08; NIH/NHLBI R01 HL073598 Core 3: 3D Imaging and Computer Modeling of the Respiratory Tract, 9/1/04-8/31/09; as well as prior support from NIH/NCRR P41 RR01243 Simulation Resource in Circulatory Mass Transport and Exchange, 12/1/1980-11/30/01 and NIH/NIBIB R01 EB001973 JSim: A Simulation Analysis Platform, 3/1/02-2/28/07.