Exhaust Gas Waste Heat Recovery

A vehicle comprising:

• an engine;
• an engine exhaust system operatively engaging the engine to direct exhaust gasses away from the engine along a main exhaust flow path, the engine exhaust system including an intermediate pipe configured to direct exhaust gasses along the main flow path;
• and
• an exhaust heat recovery heat exchanger having a sealed vacuum chamber, including an inner wall and an outer wall, a hydride pellet mounted in the chamber, and a heating element operatively engaging the hydride pellet and including electrical leads extending from the vacuum chamber;
• an exhaust chamber within the inner wall that forms a portion of the main exhaust flow path;
• a housing surrounding the outer wall and defining a heat receiving medium chamber between the housing and the outer wall, an inlet configured to receive and direct a heat receiving medium into the heat receiving medium chamber, and an outlet configured to receive and direct the heat receiving medium from the heat receiving medium chamber.

A method of selectively absorbing waste heat from exhaust gasses flowing through a main flow path of an exhaust system for a vehicle having an engine, the method comprising the steps of:

• (a) operating the engine, thereby causing exhaust gasses to flow through an exhaust chamber along the main flow path;
• (b) flowing a heat receiving medium through a heat receiving chamber surrounding the exhaust chamber;
• (c) providing a sealed vacuum chamber between the heat receiving chamber and the exhaust chamber;
• (d) determining if heat transfer from the exhaust gasses to the heat receiving medium is desired;
• and
• (e) applying an electric current to a heating element operatively engaging a hydride pellet in the vacuum chamber to thereby release hydrogen in the vacuum chamber when it is determined that heat transfer from the exhaust gasses to the heat receiving medium is desired.

A waste heat recovery heat exchanger for use along a heated fluid flow path directed from an assembly that produces a heated fluid with waste heat, the waste heat recovery heat exchanger comprising:

• a sealed vacuum chamber, including an inner wall and an outer wall, a hydride pellet mounted in the chamber, and a heating element operatively engaging the hydride pellet and including electrical leads extending from the vacuum chamber and configured to attach to a source of electrical current;
• a heated fluid chamber defined by the inner wall, the heated fluid chamber being a portion of the heated fluid flow path;
• and
• a housing surrounding the outer wall and defining a heat receiving medium chamber between the housing and the outer wall, an inlet configured to receive and direct a heat receiving fluid into the heat receiving medium chamber, and an outlet configured to receive and direct the heat receiving fluid from the heat receiving medium chamber.