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Title: Branching design of the bronchial tree based on a diameter-flow relationship

Journal Article · · Journal of Applied Physiology
OSTI ID:577019
;  [1]
  1. Boston Univ., MA (United States)

We propose a method for designing the bronchial tree where the branching process is stochastic and the diameter (d) of a branch is determined by its flow rate (Q). We use two principles: the continuum equation for flow division and a power-law relationship between d and Q, given by Q {approximately} d{sup n}, where n is the diameter exponent. The value of n has been suggested to be {approximately}3. We assume that flow is divided iteratively with a random variable for the flow-division ratio, defined as the ratio of flow in the branch to that in its parent branch. We show that the cumulative probability distribution function of Q, P(>Q) is proportional to Q{sup -1}. We analyzed prior morphometric airway data and found that the cumulative probability distribution function of diameters, P(>d), is proportional to d{sup -n}, which supports the validity of Q {approximately} d{sup n} since P(>Q) {approximately} Q{sup -1}. This allowed us to assign diameters to the segments of the flow-branching pattern. We modeled the bronchial trees of four mammals and found that their statistical features were in good accordance with the morphometric data. We conclude that our design method is appropriate for robust generation of bronchial tree models. 36 refs., 7 figs., 3 tabs.

DOE Contract Number:
AC04-76EV01013
OSTI ID:
577019
Journal Information:
Journal of Applied Physiology, Vol. 82, Issue 3; Other Information: PBD: Mar 1997
Country of Publication:
United States
Language:
English