�?�?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 Given that multiple sort of drilling fluid loss can present sometimes, it's important to find out the loss sorts and assess proportion of each and every loss form so as to ascertain the most important and secondary loss kin