Visualization of Flow and Impact Process of Oils Used in Shirodhara Treatment on a Flat Plate Under the Influence of Gravity

Shirodhara is an Ayurvedic process for treating various psychological ailments like depression, anxiety, mental stress, insomnia, headache, etc. It requires a narrow laminar low-speed stream of a medicinal fluid, in most of the cases, Mahanarayana or Ksheerabala Oil to be impacted on to the human forehead under the influence of gravity for a prescribed period of time, under controlled temperature (Pavana and Manoj in K. Rajagopalan ayurveda series 3:18, 2010 [1]; Vagbhaṭa, Ashtanga hridaya-with commentary of aruna dutta and hemadri. Reprint ed. Varanasi: Chowkhambha Sanskrit Series, 1946 [2]). Shirodhara is a dynamic process and despite being a very popular treatment method, just like other Ayurvedic treatments, it also relies on empirical rules. Hence, there is a need for a systematic scientific study of this treatment process. To understand the complete functioning of Shirodhara process, there is a necessity to visualize the fluid flow process during the treatment. We perform simple visualization of the fluid flow process under the influence of gravity coming out of a hanging Shirodhara pot (usually made up of brass). The two most commonly used oils in this treatment process are Ksheerabala and Mahanarayana oils and hence, those two have been visualized. Since the flow is axisymmetric, we have considered only one half of the flow from the images. The height differential between the outlet of Shirodhara pot and the impact plate is not very large and the velocities are also low, therefore, the images are captured using the low-speed camera as the disturbances are of negligible order. The images are processed using a MATLAB script to draw the contours of the boundary of the flow and then they are compared to the existing solutions.