When someone says \"Blockchain Simulator\" he is probably thinking about a test environment where you can test different methods prior to executing them on a live blockchain, where some errors and effects are huge. This is what you need to try out.
IBM Hyperledger: The IBM hyperledger is eliminating the miners by providing an interface where the consensus within the network is derived by 51% majority of independently run servers. It is a program that is pretty simple to use and makes use of Chain-code to deliver and execute contracts. It is providing the service of using the free developer version prior to developing one.
Ethereum Test Net: If some application created by some user on Ethereum has long term change effects on usage, Ethereum provides test net where the users could test their application to make sure it is functional just like the developer want to be. This is pretty important because directly deploying contracts on the blockchain could have irreversibly effects.
Bitcoin Testnet: Just like Ethereum\'s testnet, Bitcoin is also providing service for its users to test their application and make sure that are functional and behaving as developer expected.
Multichain: It is probably the cheapest method for developing a live blockchain. It is so cheap that you could develop two blockchain on you own machine, one as a test and the second one as a live version. Multichain is using method called streams that have ability to execute smart contracts.
Addendum: Almost every blockchain testing simulator employs a different protocol that is differing from others. There are surely more than ten methods by which one could feature a fully fledged testing scenario.