Scale variability in convection-driven MHD dynamos at low Ekman number Export

@article{takahashi08b, abstract = {We have undertaken a numerical study of convection-driven MHD dynamos in a rapidly rotating spherical shell with the Ekman number, E , down to 2×10 −6 and the magnetic Prandtl number, Pm , down to 0.2. We focus on the characteristic scales of the flow and the magnetic field. Smaller-scale convection vortices responsible for generating the magnetic field appear at lower Ekman numbers, while the scale of the magnetic field shows less variation compared with the flow. As a result, scale separation between the flow and the magnetic field occurs as the Ekman number is decreased. Scale separation helps dynamos to maintain the magnetic field at P m <1 through increase in the effective value of the magnetic Reynolds number.}, author = {Takahashi, F. and Matsushima, M. and Honkura, Y.}, citeulike-article-id = {2745782}, citeulike-linkout-0 = {http://dx.doi.org/10.1016/j.pepi.2008.03.005}, citeulike-linkout-1 = {http://linkinghub.elsevier.com/retrieve/pii/S0031920108000514}, citeulike-linkout-2 = {http://www.sciencedirect.com/science/article/B6V6S-4S3WX0X-1/1/9f85c934cf775f703894c2c92b5bbef5}, doi = {10.1016/j.pepi.2008.03.005}, issn = {00319201}, journal = {Physics of the Earth and Planetary Interiors}, keywords = {convection, dynamo, earth-core}, month = {April}, number = {3-4}, pages = {168--178}, posted-at = {2009-10-26 17:50:38}, priority = {5}, title = {Scale variability in convection-driven MHD dynamos at low Ekman number}, url = {http://dx.doi.org/10.1016/j.pepi.2008.03.005}, volume = {167}, year = {2008} }

TY - JOUR ID - takahashi08b L3 - citeulike-article-id:2745782 N2 - We have undertaken a numerical study of convection-driven MHD dynamos in a rapidly rotating spherical shell with the Ekman number, E , down to 2×10 −6 and the magnetic Prandtl number, Pm , down to 0.2. We focus on the characteristic scales of the flow and the magnetic field. Smaller-scale convection vortices responsible for generating the magnetic field appear at lower Ekman numbers, while the scale of the magnetic field shows less variation compared with the flow. As a result, scale separation between the flow and the magnetic field occurs as the Ekman number is decreased. Scale separation helps dynamos to maintain the magnetic field at P m <1 through increase in the effective value of the magnetic Reynolds number. IS - 3-4 JF - Physics of the Earth and Planetary Interiors SN - 00319201 EP - 178 TI - Scale variability in convection-driven MHD dynamos at low Ekman number VL - 167 SP - 168 KW - convection KW - dynamo KW - earth-core AU - Takahashi, F AU - Matsushima, M AU - Honkura, Y PY - 2008/04// UR - http://dx.doi.org/10.1016/j.pepi.2008.03.005 ER -