Gas Engine Power Plant Heat Transfer Circuit for LNG Evaporation

A heat transfer fluid circuit is introduced as an intermediary between the engine waste heat and the LNG evaporator. The fluid circulates through both the engine cooling system and the evaporator, enabling thermal energy transfer without direct thermal coupling. This mediator approach simplifies temperature control by decoupling the heat source and heat sink while maintaining efficient energy utilization.

The heat transfer fluid circuit serves multiple functions simultaneously: it cools the engine, evaporates the LNG, and can be directed to the central cooler when needed. By making the thermal management system universal, the patent resolves the contradiction by enabling flexible heat distribution that improves overall efficiency while maintaining manageable complexity through integrated control.

The system dynamically adjusts the operation of the central cooler based on real-time thermal demands. The controller monitors temperature requirements and activates or deactivates the central cooler accordingly, enabling the system to optimize heat transfer efficiency when needed while preserving useful thermal energy during other operating conditions. This dynamic control resolves the contradiction by making thermal management adaptive rather than static.

A control system with temperature sensors and actuators implements feedback control of the heat transfer fluid circuit. The controller receives temperature information from various points in the system and adjusts the central cooler operation and fluid flow distribution to maintain optimal performance. This feedback mechanism ensures that the central cooler is used only when necessary to improve heat transfer, thereby minimizing loss of useful thermal energy while maintaining efficiency when required.

The patent utilizes the phase transition of LNG from liquid to gas within the evaporator system. By designing the fuel delivery system to leverage this natural phase change driven by heat transfer from the engine, the patent reduces the need for complex high-pressure storage and pumping systems. The phase transition approach simplifies the fuel delivery infrastructure while maintaining continuous gas mode operation capabilities and associated emission benefits.

The engine's own waste heat is used to evaporate the LNG fuel in the main gas evaporator, creating a self-service thermal management system. This eliminates or reduces the need for separate heating systems, external power sources for fuel vaporization, and complex temperature control equipment. The fuel storage and delivery system becomes simpler because it leverages the engine's inherent thermal output, thereby reducing device complexity while maintaining continuous gas operation and emission reduction benefits.