Date of Award
Doctor of Philosophy in Industrial Engineering - (Ph.D.)
Mechanical and Industrial Engineering
George Hanna Abdou
Paul G. Ranky
Athanassios K. Bladikas
Ismet Esra Buyuktahtakin-Toy
This research explores the use of waterjet (WJ) technology in performing skin incisions. The study defines the analytical relationships between the skin properties and the operating parameters of the WJ which include the skin thickness, its elastic modulus, the WJ pressure, the nozzle’s orifice diameter, its stand-off distance and the traverse speed of the WJ as well as the duration of applying the WJ pressure. An analytical model is developed to measure the depth incision of the skin, the water pressure and the water velocity, while using a WJ. Systemization and optimization models that determine the optimal operating parameters levels to maximize the depth of incision as well as a specific target, accompany the analytical model.
The study also validates the developed models using literature as well as experimental verification. In the literature verification of previous work done using WJ to cut through bone cement, the percent error between the calculated depth of cut and the measured depth of cut ranged from as low as 2% to 11% error. The experimental verification uses a local WJ device to make cow skin and bone incisions. The percent error between the calculated depth of cut and the measured depth of cut ranged from as low as 9% to 23% error.
In order to illustrate the accuracy of the proposed models, they are applied to a case study: Cesarean section procedure. The analysis of results shows that the most significant factors that affect the depth of cut are the nozzle’s orifice diameter, the water pressure, the nozzle’s loss coefficient and the traverse speed of the WJ. Using the results of the study, it is concluded that to make a 2.30 mm deep abdomen skin incision when the elastic modulus is 1 GPa, the optimal WJ operating parameters are 12.5 MPa water pressure with 0.3 mm nozzle’s orifice diameter, 17 mm/s traverse speed and 0.15 nozzle’s loss coefficient.
Atalla, Nadi, "Interventions of waterjet technology in skin incisions" (2019). Dissertations. 1396.