Model number


Mechanics of a rigid resistive bronchiole with compliant alveolar sac. The driving pressure is at entrance to the bronchiole; the reference extrathoracic pressure is constant at zero.


 This model represents a rigid bronchiole with a compliant alveolar sac. 
 The resistance offered by bronchial wall to the flow of air is represented by
 the resistor in the model. The alveolar sac compliance is repsented by a capcitor.
 This model lacks the pleural pressure because of which a pressure pulse
 is used to drive the model.The pressure pulse represents the pressure difference
 in the alveolar space and the pleural sac. The alveolar sac changes
 its volume as a function of inlet flow or pressure. For a step function in the pressure
 the volume of the alveolar sac increases as an exponential function.  

fig 1

Figure Legend:
Finlet: Inlet Flow, P: Pressure, R: Resistance, F: Flow, Com: Compliance, V: Volume.


Pinlet - P2 = Finlet * R1
P2 - P3 = Finlet * R2
P3 - P4 = (V1 - V1_0)/Com1
d(V1)/dt = Finlet

Where: P is pressure, F is flow, R is resistance, Com is capacitance, and V is the volume. 
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Help running a JSim model.

  K. R. Lutchen and G. M. Saidel, "Estimation of mechanical parameters in multicompartment models 
  applied to normal and obstructed lungs during tidal breathing," IEEE Trans. Biomed. Eng., vol. BME-33, no. 9, pp. 878-887, Sept. 1986.

  Levitzky MG. "Mechanics of Breathing", Pulmonary Physiology. 7th Edition, New York: McGraw-Hill, 2007, p. 11?53
Key terms
Alveolar sac
lung mechanics
positive pressure ventilation
chest wall compliance
Respiratory System
Respiratory mechanics

Please cite https://www.imagwiki.nibib.nih.gov/physiome 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 https://www.imagwiki.nibib.nih.gov/physiome 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.