This study examines the heat transfer enhancement from a horizontal rectangular fin embedded with triangular perforations （their bases parallel and toward the fin tip） under natural convection. The fin＇s heat dissi...This study examines the heat transfer enhancement from a horizontal rectangular fin embedded with triangular perforations （their bases parallel and toward the fin tip） under natural convection. The fin＇s heat dissipation rate is compared to that of an equivalent solid one. The parameters considered are geometrical dimensions and thermal properties of the fin and the perforations. The gain in the heat transfer enhancement and the fin weight reduction due to the perforations are considered. The study shows that the heat dissipation from the perforated fin for a certain range of triangular perforation dimensions and spaces between perforations result in improvement in the heat transfer over the equivalent solid fin. The heat transfer enhancement of the perforated fin increases as the fin thermal conductivity and its thickness are increased.展开更多
With the increase of high-power electrical components in modern ships,especially fully electric ships with electric propulsion drive(EPD),the cooling of EPD electrical components has become particularly important.Prov...With the increase of high-power electrical components in modern ships,especially fully electric ships with electric propulsion drive(EPD),the cooling of EPD electrical components has become particularly important.Providing optimal configurations for heat sinks with high thermal efficiency plays an essential role in this regard.A new technique for improving the efficiency of heat sinks is the utilization of perforated fins.This study examined the effects of perforation geometry(shape and size)on laminar airflow flow and heat transfer characteristics over a perforated plate-fin heat sink.Three-dimensional simulations were conducted using the finite-volume scheme based on the SIMPLE algorithm.In this research,the effects of perforation shape and size on various parameters,e.g.,total drag force,average Nusselt number,perforated fin efficiency(PFE),heat transfer performance enhancement(HTPE),and fin optimization factor(η)were evaluated.The results confirmed that at a specific heat transfer surface area for perforated fins,the highest efficiency is achieved by circular perforations.In contrast,the square perforations due to geometric similarity to rectangular fins could reach the maximum size.Consequently,fins with square perforations could achieve the most optimal configuration.Also,results showed that for a constant perforations size,change in perforations shape improves HTPE,PFE,andηby more than 40%,45%,and 110%,respectively.Also,by modifying perforations size for a specified shape,an increment of more than 35%,40%,and 150%is observed in HTPE,PFE,andη,respectively.展开更多
Fins are the extended surfaces through which heat transfer takes place to keep the surface cool. Fins of various configurations are presently used ranging from automobile engine cooling to cooling of computer parts. N...Fins are the extended surfaces through which heat transfer takes place to keep the surface cool. Fins of various configurations are presently used ranging from automobile engine cooling to cooling of computer parts. Note that in a fin majority of the heat transfer to atmosphere is by convection and therefore in the present research, and importance is given to variation of temperature along the length of the fin which in turn gives rate of heat transfer. In the present research a solid rectangular aluminum fin and the same rectangular fin with different perforations (2, 4, 8 and 10) were compared analytically, experimentally and its validity through finite element analysis for its temperature distribution along the length. From the present research it is observed that the mathematical and FEA for a solid rectangular fin without perforations are converging within ±1°C and rectangular fin with 10 perforations are converging within ±2°C and hence the validity.展开更多
文摘This study examines the heat transfer enhancement from a horizontal rectangular fin embedded with triangular perforations （their bases parallel and toward the fin tip） under natural convection. The fin＇s heat dissipation rate is compared to that of an equivalent solid one. The parameters considered are geometrical dimensions and thermal properties of the fin and the perforations. The gain in the heat transfer enhancement and the fin weight reduction due to the perforations are considered. The study shows that the heat dissipation from the perforated fin for a certain range of triangular perforation dimensions and spaces between perforations result in improvement in the heat transfer over the equivalent solid fin. The heat transfer enhancement of the perforated fin increases as the fin thermal conductivity and its thickness are increased.
文摘With the increase of high-power electrical components in modern ships,especially fully electric ships with electric propulsion drive(EPD),the cooling of EPD electrical components has become particularly important.Providing optimal configurations for heat sinks with high thermal efficiency plays an essential role in this regard.A new technique for improving the efficiency of heat sinks is the utilization of perforated fins.This study examined the effects of perforation geometry(shape and size)on laminar airflow flow and heat transfer characteristics over a perforated plate-fin heat sink.Three-dimensional simulations were conducted using the finite-volume scheme based on the SIMPLE algorithm.In this research,the effects of perforation shape and size on various parameters,e.g.,total drag force,average Nusselt number,perforated fin efficiency(PFE),heat transfer performance enhancement(HTPE),and fin optimization factor(η)were evaluated.The results confirmed that at a specific heat transfer surface area for perforated fins,the highest efficiency is achieved by circular perforations.In contrast,the square perforations due to geometric similarity to rectangular fins could reach the maximum size.Consequently,fins with square perforations could achieve the most optimal configuration.Also,results showed that for a constant perforations size,change in perforations shape improves HTPE,PFE,andηby more than 40%,45%,and 110%,respectively.Also,by modifying perforations size for a specified shape,an increment of more than 35%,40%,and 150%is observed in HTPE,PFE,andη,respectively.
文摘Fins are the extended surfaces through which heat transfer takes place to keep the surface cool. Fins of various configurations are presently used ranging from automobile engine cooling to cooling of computer parts. Note that in a fin majority of the heat transfer to atmosphere is by convection and therefore in the present research, and importance is given to variation of temperature along the length of the fin which in turn gives rate of heat transfer. In the present research a solid rectangular aluminum fin and the same rectangular fin with different perforations (2, 4, 8 and 10) were compared analytically, experimentally and its validity through finite element analysis for its temperature distribution along the length. From the present research it is observed that the mathematical and FEA for a solid rectangular fin without perforations are converging within ±1°C and rectangular fin with 10 perforations are converging within ±2°C and hence the validity.
