�?�?t ε l ρ l v l + �?�?ε l ρ l v l v l = ε l �?�?τ l + ε l ρ l g �?ε l �?p �?β v l �?v s The lessen in annular return move will trigger the flow speed of drilling fluid https://socialbuzzfeed.com/story7338136/drilling-mud-loss-things-to-know-before-you-buy