In the following from the last time, I would like to consider making a handy portable cooler using Peltier. I’m trying t
o make the specification power supply a mobile battery or an AA battery from the point where I aim for handy, but this time I will consider it with a mobile battery once. When I chose the one with the large output as much as possible, the following was found f
or the time being. – Mobile battery large capacity 25800mAh quick mobile charger 5
V / 2.1A output https:/
/www.amazon.co.jp / dp / B084C84F12 So it is up to 5V, 2.1A. I would like to estimate how far this p
ower can cool down. I tried to estimate it to
match this power in the Peltier design example of the previous paper (“I
nvestigation of electronic cooling elements and application circuit production” _ Setsunan University). In addition, when the outside temperature was set to 35 °C
and the heat dissipation side temperature was set to 40 °C at 35 °C + 5, the case of he
at dissipation with an air-cooled fan was calculated.
| Material Surface Area S[mm2] | 41762 | |||
| Ambient temperature Te[deg] | 35 | Fixed | ||
| Set temperature Tc[deg] | 25 | |||
| Heat transfer resistance 1/α[m2・K/W] | 0.137 | ← air | ||
| T[mm] | 1 | |||
| Thermal conductivity of insulation λ[W/m・K] | 0.025 | |||
| Inflow heat Qsi from the surroundings via insulation[W] | 2.4 | |||
| Coolant volume V[mm3] | 1044579.55731861 | |||
| Specific heat C[J/kgK] | 881 | |||
| Specific gravity p[kgm3] | 2700 | |||
| Coolant initial temperature To[deg] | 35 | |||
| Time to set temperature[sec] | 3600 | |||
| Amount of heat to cool the coolant Qτ[W} | 6.9 | |||
| Amount of heat required for Peltier elements per unit of time Qc[W] | 9.3 | Qsi+Qτ | ||
| Heat dissipation surface temperature Th[deg] | Forty. | Te+5 | ||
| Voltage[V] | 4 | ＜5 | ||
| Current[A] | 1.3 | < 2, selected from temperature difference ΔT = Th-Tc | ||
| Power supplied to heat dissipation surface temperature Th Wp[W] | 5.2 | |||
| Heat dissipation Qh from Peltier element[W] | 14.5 | |||
| Required thermal resistance θ[K/W] | 0.35 | > air-cooled resistance 0.3 |
As a result of the above calculation, the temperature that can be
cooled was … “25 °C”. Well, if it is 25 °C for the outsid
e temperature of 35 °C, you may feel cold, but it is weak. Too weak. I was expecting a more keen and co
ld one, but it was 25 °C. This time I calculated it with Peltier
who was riding the paper, so if you choose the more optimal one, it may change, but is there such a big difference? Well, but there
are some handy things (e.e. Eberwave) in the world, so what about? Is it a thing of about 25 °C in ability, or i
s it cooled using a high-tech that can not be imagined, is the above calculation matched in the first place? Is it a place? Well, is the calculation ba
d? I may be doing some calculations differently. Whether to take the take t
he time to try out prototypes. However, when I look at the above results, I feel motivated.
