If you are planning to have Web tier on both nodes, then Load Balancer of any sort is required, if only appl_top is shared and web runs on one tier and Concurrent on other tiers then Load Balancer is not required. I would suggest you go with Load Balancer as you have 2 nodes.
Yes, We are planing to have webtier and concurrent on both the nodes.
We have to use load balancer as i was guessing.
Yes that's right. If you have more than one application node , you need to implement load-balancing.