Harald Andreas Næser

• Næser, Harald Andreas (2022). The capillary waves' contribution to wind-wave generation. Fluids. 7(2). doi: 10.3390/fluids7020073. Full text in Research Archive Show summary

  Published theories and observations have shown that dissipation of gravity waves implies frequency downshifting of wave energy. Hence, for wind-waves, the wind energy input to the highest frequencies is of special interest. Here it is shown that this input is vital, because the direct wind energy input obtained by the air-pressure’s work on most gravity waves is slightly less than what the waves need to grow. Further, the wind’s input of the angular momentum that waves need to grow is found to be absent at most gravity wave frequencies. The capillary waves that appear at the surface of the sea when the wind is blowing solve these problems. To demonstrate this, an extension of linear wave theory is established to study possibilities and limitations for transfer of energy and angular momentum from the wind to waves through these frequencies. The theory describes regular, gravity–capillary waves with constant amplitude under laminar conditions. It includes surface tensions, viscosity, gravity and a wind-generated shear current, and shows that these waves—contrary to most gravity waves—receive more energy from the wind than they dissipate and angular momentum they cannot keep. Hence, the problem of the missing input of energy and angular momentum from wind to gravity waves is solved by transfers through the capillary waves. This implies that capillary waves are vital to obtain growing gravity waves.

• Næser, Harald Andreas (2002). Conservation of "Partial Energy", with an Application on Water Wave Dissipation. Journal of Applied Sciences. ISSN 1812-5654. 2(6), p. 663–666. doi: https:/scialert.net/abstract/?doi=jas.2002.682.685. Full text in Research Archive Show summary

  An extension of the energy conservation theorem is established for fluid dynamical purposes. Equations are developed that divide the mechanical energy of a system into three "partial energies" based on the three orthogonal directions of a Cartesian coordinate system. In addition to terms similar to the terms of ordinary energy equations, these equations contain terms that handle transfer of energy within a fluid, i.e. between the three partial energies. Thereby internal transfer of energy can be studied. A brief study, that gives a consequence of viscous dissipation on water waves, is included as an example.

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• Næser, Harald (1998). Dynamikk, Fysikk for ingeniører. Cappelen Damm Høyskoleforlaget. ISBN 9788276341324. 302 p. Full text in Research Archive

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• Næser, Harald Andreas (2022). The capillary wave's contribution to wind-wave generation. Full text in Research Archive
• Næser, Harald Andreas (2022). Haralds bølger. Full text in Research Archive
• Næser, Harald Andreas (2014). Klimaforandringer og fornybar energi. Full text in Research Archive
• Næser, Harald Andreas (2014). Energías renovables aplicables en RD. Full text in Research Archive
• Næser, Harald Andreas (2014). Fornybar oppvarming - Løsninger for norske hjem. Full text in Research Archive
• Næser, Harald Andreas (2014). Fornybar oppvarming - Løsninger for norske hjem. Full text in Research Archive
• Næser, Harald Andreas (2014). Energias Renovables: Recientes Avances. Full text in Research Archive Show summary

  Se le dio una visión general de las diferentes plantas de energía renovable

• Næser, Harald Andreas (2014). Fornybar oppvarming, Løsninger for norske hjem. Full text in Research Archive
• Næser, Harald Andreas (2013). Future possibilities for renewable energies. Full text in Research Archive
• Næser, Harald Andreas (2013). Posibilidades futuras de las energías renovables en Republica Dominicana. Full text in Research Archive
• Næser, Harald Andreas (2013). Fornybar energi, klimaforandringer og bærekraftig utvikling. Full text in Research Archive
• Næser, Harald Andreas (2013). Fornybar energi og klimaproblemet. Full text in Research Archive
• Næser, Harald Andreas (2012). Hvorfor vindsjø vokser. Kysten. ISSN 0332-9550. p. 40–41. Full text in Research Archive
• Næser, Harald Andreas (2012). Bølger fra fartøyer. Kysten. ISSN 0332-9550. p. 32–33. Full text in Research Archive
• Næser, Harald Andreas (2012). Introducción a la hidráulica de tubos. Full text in Research Archive
• Næser, Harald Andreas (2012). Hvorfor vind lager bølger. Kysten. ISSN 0332-9550. p. 32–33. Full text in Research Archive
• Næser, Harald Andreas (2012). Bølger på langtur. Kysten. ISSN 0332-9550. p. 32–33. Full text in Research Archive
• Næser, Harald Andreas (2012). Fornybar energi. Full text in Research Archive
• Næser, Harald Andreas (2012). Bølger som møter land. Kysten. ISSN 0332-9550. p. 32–33. Full text in Research Archive
• Næser, Harald (2000). Om bevaring av spinn i bølger. Full text in Research Archive
• Næser, Harald (2000). Vind, bølger og strøm som energikilde. Full text in Research Archive
• Næser, Harald (1999). Bølgekraftverk gjennom 200 år. ?. p. 28–28. Full text in Research Archive

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