I want to delete some devices from my developer account as it has already reached to its limit of 100. So before deleting device I just want to confirm what kind of effect it will have on provisioning profiles in which those devices are added.
No, any change in device list will not affect provisioning profile. Only the devices you will remove, will no longer be accessible to the app and provisioning profile in those (removed) devices will become invalid.
Here is more details about how to manage your provisioning profiles & devices.
Maintaining Identifiers, Devices, and Profiles
You can disable and enable a device, but you can’t delete it from your developer account. You can disable a device you no longer use for development or testing. However, doing so invalidates provisioning profiles that contain the device and doesn’t increase your total count of devices for the year. You can also enable a device that you previously disabled.
Also note, You can't add any (more) new device inplace of removed devices, if you've reached maximum limit of allowed devices in your developer account. Apple just disable device in your developer account, not removes permanently until you renew your developer account (Disabling device in developer account not removes device from developer account). So count (number) of devices will not reduce, if you disable/remove any device from developer account.