An internal combustion engine having an independent combustion chamber comprises a combustion chamber (1), an air inlet system (2), a material feeding system (3), and a working system (4). The air inlet system (2) and the combustion chamber (1) are connected together and configured to transport a compressed air to the combustion chamber (1). The material feeding system (3) and the combustion chamber (1) are connected together and configured to transport a fuel to the combustion chamber (1). The combustion chamber (1) has a fixed volume and has no movable wall such as a piston. The fuel continues to be burned in the combustion chamber (1) to generate a high-temperature and high-pressure gas, and chemical energy of the fuel is converted into internal energy of the high-temperature and high-pressure gas. The working system (4) and the combustion chamber (1) are connected together. The piston (21) of the working system (4) works to convert the internal energy of the gas into a mechanical energy.

An internal combustion engine having an independent combustion chamber comprises a combustion chamber (1), an air inlet system (2), a material feeding system (3), and a working system (4). The air inlet system (2) and the combustion chamber (1) are connected together and configured to transport a compressed air to the combustion chamber (1). The material feeding system (3) and the combustion chamber (1) are connected together and configured to transport a fuel to the combustion chamber (1). The combustion chamber (1) has a fixed volume and has no movable wall such as a piston. The fuel continues to be burned in the combustion chamber (1) to generate a high-temperature and high-pressure gas, and chemical energy of the fuel is converted into internal energy of the high-temperature and high-pressure gas. The working system (4) and the combustion chamber (1) are connected together. The piston (21) of the working system (4) works to convert the internal energy of the gas into a mechanical energy.

An alternative heat source for an internal combustion engine with an elongated compartment with first and second ends, a directed energy device capable of sending a pulse of photonic energy to a focal point within the first end of the compartment, an intake allowing for the entry of a gas into the the elongated compartment, an exhaust allowing for the exit of the gas from the elongated compartment, and a piston capable of moving within the elongated compartment between the first and second ends. The pulse of photonic energy at the focal point heats the gas and causes a corresponding expansion of the gas in the elongated compartment, driving the piston toward the second end of the elongated compartment, where the piston movement can be translated into motive force. The same principle can work with a rotary chamber, or a dual chambered linear system.