AvailableGB per queue is not the same as AvailableGB per queue per user when the user limit is set to 100%.
i.e. if the total available GB of the cluster is 60, and queue "default" has 92% capacity with 100% as the user limit, AvailableGB per queue default = 55 (i.e. 0.92*60) whereas AvailableGB per queue for user ramya is 56 (however it should be 55 = 0.92*60*1)
Also, unlike the AvailableGB/queue, AvailableGB/queue/user is not decremented when user ramya is running apps on the "default" queue.