Characterization and Modeling of Thoraco-Abdominal Response to Blast Waves. Volume 3. Lung Dynamics and Mechanical Properties Determination
Abstract
Four experiments are performed to determine the mechanical properties of lung tissue: 1. Measurement of the incremental bulk modulus, K. The equipment imposes incremental changes to the lung volume and measures the corresponding transpulmonary pressure. From the pressure-volume curves the bulk modulus is computed. 2. Measurement of the incremental Young's modulus, E. Two types of measurements are done: a. A known vertical deflection is applied on the pleural surface and the corresponding vertical load is measured. b. A circular flexible polyethylene membrane of various diameters (7 mm to 16 mm, depending on the size of the lung) is cemented to a flat portion of the pleura, and a vertical deflection is applied on the center of the membrane. 3. Measurement of material constants for human lungs in large deformation. This consists of two parts: a. The TRIAX testing machine, designed and constructed in our laboratory earlier, was used to measure the tissue components of the human lung stress-strain relationship. b. Pressure-volume curves of air-filled human lungs are measured. This work is done in Dr. Sobin's laboratory in Los Angeles where fresh specimens can be obtained and tested as soon as they arrive in the laboratory. 4. Measurement of Wave Propagation in the Lung. For convenience of detailed examination, excised lungs are used. A small shock tube is used to impose impact loading on the lung. Pressure transducers are used to sense the shock and the stress waves. The speed of wave propagation is determined from the first arrival time of the pressure wave front and known distance between sensors. Keywords: Wounds and injuries; Blast waves; Blast loads; Stress(Physiology).
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1985
- Accession Number
- ADA189669
Entities
People
- M. R. Yen
- Y. C. Fung
- Y. J. Zeng