effect of solution contact angle with KCl and NaCl ore on dissolution rate

I am working on a potash solution mining project (NaCl solution injection) and it is said that in the mine cavern, the contact angle of the solution with cavern wall can have impact on the dissolution rates, i.e. on the bottom of the cavern, the dissolution rate is much lower than at the top of the cavern (due to a variety of factors), but we are just trying to capture it with a multiplier on the default rate (the kind of rate measured in lab on vertical surface).


Here is a very rough diagram showing inside the cavern, solutions are injected into it to dissolve ore on all faces. On all surfaces, solution and brine will enter and leave and there will be some flow along those angled faces, which will result in some differences in the dissolving rates.


[![enter image description here](https://i.stack.imgur.com/gW4IK.png)](https://i.stack.imgur.com/gW4IK.png)


I did a lot of search online and in various libraries, journal articles, lab reports, I am surprised that there is very scant information on this (i.e. contact face's orientation impact on dissolution rate). Any pointers would be greatly appreciated.


