I want to know if the sensor nodes in any cluster in a wireless sensor network may detect events in a different ratio i.e.some nodes could detect events more others in the same cluster, so is power consumption in these nodes will be higher than other nodes? i want to know if there is an application in which this assumption or question is possible with take in our concentration that we can applied clustering to increase the lifetime of this network.
The function of a node and how it interacts on the mesh network (assuming a mesh-connected node) are two different things.
Such nodes almost certainly will have a microcontroller in them that performs the node function, like measuring temperature periodically or whatever. This micro then also usually decides when it should attempt to communicate on the mesh network.
Obviously, the micro can take many measurements per mesh connection, or connect many times without taking any measurements. The two are independent.
If the mesh is only powered up at regular intervals, then a node can't report any data no matter what activity it might detect. It has to wait until the next mesh interval. Until then, it has no way to pass on any of its data.
Some nodes might consume more power if whatever they are connected to is more active. Such activity could cause a node to wake up and do something, then go back to low power state until the next event. Other types of nodes just sample something periodically, so wouldn't take more power. It's all up to whatever policies are encoded in the firmware of the micro.