A hollow poppet valve (10) has an internal cavity (S) which comprises a diametrically large valve head cavity (S1) formed in a valve head (14) and a diametrically small stem cavity (S2) formed in a stem (12) in communication with the valve head cavity (S1). The stem cavity has a diametrically larger first portion (S21) near the end of the stem and a diametrically smaller second portion (S22) near the valve head. A step (17) is formed at the boundary of the first and the second portion of the stem cavity (S2). The internal cavity is loaded with a coolant to a level above the step, together with an inert gas. In response to a reciprocal motion of the valve, turbulent flows of coolant (F9) are created in the neighborhood of the step (17), facilitating active stirring of the coolant (19) in the cavity (S).

A heat exchanging valve arrangement includes, a manifold defining a chamber, a first passageway, a second passageway, a third passageway, and a fourth passageway, and a member movable relative to the manifold configured to define fluidic communication between the first passageway and the second passageway when in a first position and between the first passageway and the third passageway when in a second position, fluid is flowable into the chamber through the fourth passageway such that fluid is exposed to surfaces of the member regardless of whether the member is in the first position or the second position.

A poppet valve, in particular, a hollow poppet valve, can include a valve stem; a valve cap; a valve body comprising a longitudinal axis with a stem end to which the valve stem is arranged and a cap end to which the valve cap is arranged, the valve body further comprising a cavity with a stem opening towards the stem end and a cap opening towards the cap end; wherein the stem opening of the cavity is configured to be closed by the valve stem and the cap opening of the cavity is configured to be closed by the valve cap; wherein the valve cap comprises a cap wall protruding into the cavity along an interior circumference of the valve cap; and wherein the cap wall comprises a cap wall formation.