A jet-flow heat exchanging device (100, 200, 300, 400, 500, 600, 700, 800) for transferring heat from or to one or more heat transfer surfaces (120, 220, 320, 420, 520, 620, 720, 820), comprising: - one or more orifice groups (115, 215a, 215b, 315a, 315b, 415a, 415b, 515a, 515b, 615a, 615b, 715, 815), each for directing a heat carrier medium onto the heat transfer surface (120, 220, 320, 420, 520, 620, 720, 820); wherein at least one of the orifice groups (115, 215a, 215b, 315a, 315b, 415a, 415b, 515a, 515b, 615a, 615b, 715, 815) includes: - a main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806) for generating a main jet-stream; and - at least two control orifices (107, 207a, 207b, 307a, 307b, 407a, 407b, 507a, 507b, 607a, 607b, 707, 807) associated with the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806), characterized in that the control orifices (107, 207a, 207b, 307a, 307b, 407a, 407b, 507a, 507b, 607a, 607b, 707, 807) are configured - to have a smaller cross-section than the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806); - to be arranged symmetrically around a first axis going through the center of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806), wherein the first axis is perpendicular to the flow direction through the main orifice and perpendicular to the heat surface transfer surface in the chamber; - to be offset from a second axis towards the heat transfer surface, the second axis going through the center of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806) and being perpendicular to the first axis and to the flow direction, and - to have a distance from the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806) of between 1% and 80% of the largest cross-sectional dimension of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806), respectively; in order to generate control jet-streams for interacting with the main jet-stream, so as to cause the heat carrier medium of the main jet-stream to swirl. - one or more orifice groups (115, 215a, 215b, 315a, 315b, 415a, 415b, 515a, 515b, 615a, 615b, 715, 815), each for directing a heat carrier medium onto the heat transfer surface (120, 220, 320, 420, 520, 620, 720, 820); wherein at least one of the orifice groups (115, 215a, 215b, 315a, 315b, 415a, 415b, 515a, 515b, 615a, 615b, 715, 815) includes: - a main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806) for generating a main jet-stream; and - at least two control orifices (107, 207a, 207b, 307a, 307b, 407a, 407b, 507a, 507b, 607a, 607b, 707, 807) associated with the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806), characterized in that the control orifices (107, 207a, 207b, 307a, 307b, 407a, 407b, 507a, 507b, 607a, 607b, 707, 807) are configured - to have a smaller cross-section than the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806); - to be arranged symmetrically around a first axis going through the center of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806), wherein the first axis is perpendicular to the flow direction through the main orifice and perpendicular to the heat surface transfer surface in the chamber; - to be offset from a second axis towards the heat transfer surface, the second axis going through the center of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806) and being perpendicular to the first axis and to the flow direction, and - to have a distance from the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806) of between 1% and 80% of the largest cross-sectional dimension of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806), respectively; in order to generate control jet-streams for interacting with the main jet-stream, so as to cause the heat carrier medium of the main jet-stream to swirl. - to have a smaller cross-section than the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806); - to be arranged symmetrically around a first axis going through the center of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806), wherein the first axis is perpendicular to the flow direction through the main orifice and perpendicular to the heat surface transfer surface in the chamber; - to be offset from a second axis towards the heat transfer surface, the second axis going through the center of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806) and being perpendicular to the first axis and to the flow direction, and - to have a distance from the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806) of between 1% and 80% of the largest cross-sectional dimension of the main orifice (106, 206a, 206b, 306a, 306b, 406a, 406b, 506a, 506b, 606a, 606b, 706, 806), respectively;