Heat transfer apparatus and method

A heat transfer apparatus comprising:

• an air inlet and an air outlet;
• a process fluid heat exchange circuit for receiving a process fluid, the process fluid heat exchange circuit comprising:
• a heat exchanger;
• an airflow generator operable to cause air to travel from the air inlet to the air outlet and contact the heat exchanger;
• a thermal energy storage;
• and
• a mechanical cooler;
• the process fluid heat exchange circuit having a plurality of modes including:
• a first mode wherein the heat exchanger is operable to transfer heat between the process fluid and the air;
• a second mode wherein the heat exchanger is operable to transfer heat between the process fluid and the air and the mechanical cooler is operable to remove heat from the process fluid;
• and
• a third mode wherein the heat exchanger is operable to transfer heat between the process fluid and the air and the thermal energy storage is operable to remove heat from the process fluid;
• and
• a fourth mode wherein the heat exchanger is operable to transfer heat between the process fluid and the air, the mechanical cooler is operable to remove heat from the process fluid, and the thermal energy storage is operable to remove heat from the process fluid;
• a controller operatively connected to the process fluid heat exchange circuit, the controller configured to operate the process fluid heat exchange circuit in one of the plurality of modes based at least in part upon a determination of a thermal duty of the heat transfer apparatus;
• wherein the process fluid heat exchange circuit has a sixth mode wherein the heat exchanger and mechanical cooler are operable to charge the thermal energy storage;
• wherein the mechanical cooler includes a condenser and an evaporator;
• and
• wherein the process fluid heat exchange circuit in the sixth mode includes:
• a first process fluid closed loop including the evaporator of the mechanical cooler, the thermal energy storage, and a first closed loop pump to circulate a first process fluid between the evaporator and the thermal energy storage;
• and
• a second process fluid closed loop including the condenser of the mechanical cooler, the heat exchanger, and a second closed loop pump to circulate a second process fluid between the condenser and the heat exchanger.

A method of operating a heat transfer apparatus including a process fluid heat exchange circuit connecting a process fluid inlet to a process fluid outlet, the process fluid heat exchange circuit comprising:

• a heat exchanger;
• a thermal energy storage;
• and
• a mechanical cooler;
• the process fluid heat exchange circuit configured to receive a process fluid at an initial temperature and return the process fluid via the process fluid outlet at a process fluid set temperature lower than the initial temperature, the process fluid heat exchange circuit having a plurality of modes including:
• a first mode wherein the heat exchanger transfers heat between a process fluid and air;
• a second mode wherein the heat exchanger transfers heat between the process fluid and the air and the mechanical cooler removes heat from the process fluid;
• a third mode wherein the heat exchanger transfers heat between the process fluid and the air and the thermal energy storage removes heat from the process fluid;
• and
• a fourth mode wherein the heat exchanger transfers heat between the process fluid and the air, the mechanical cooler removes heat from the process fluid, and the thermal energy storage removes heat from the process fluid;
• the method comprising:
• determining a thermal duty of the heat transfer apparatus;
• and
• operating the process fluid heat exchange circuit in one of the plurality of modes based at least in part upon the thermal duty of the heat transfer apparatus.