�?�?t ρ l k + �?�?x i ρ l k v l = �?�?x j μ + μ t σ k �?k �?x j + G k �?ρ l ε �?Y M If the quantity of fluid while in the wellbore drops because of lost circulation (or any other https://vertechs.mystrikingly.com/blog/the-unseen-engine-how-drilling-fluid-powers-the-future-of-energy