Quantum Heat Transfer

Isothermal heat transfer: ∆T < 3oC

Quantum Heat Transfer Enhances Boiling Heat Transfer

Tradition

Nanofluid

Add nanoparticles into deionized water
Form homogeneous suspension and surface deposition

Increase nucleation sites density and bubble departure rates

Enhance the roughness, wettability and capillarity of the heating surface

Increase heat transfer coefficient and CHF

Results: The nucleation site density, 
     bubble departure frequency
             and heat transfer coefficient
 are reduced.                       

Innovation

Quantum Heat Transfer

Add nanoparticles into deionized water
Self-assemble the closest-packing structure
in liquid

Surface phonon polaritons coupling electromagnetic waves

Quantum heat transfer coupling heat conduction and convection

Increase heat transfer coefficient and CHF

Results: Heat transfer coefficient is 
             improved and thermal resistance is
             reduced. CHF of boiling heat transfer
             is significantly enhanced.

Four Key Inventions of Quantum Heat Transfer Technology
 

Globally first to enhance boiling heat transfer by quantum heat transfer

Introduce a New Concept of Evanescent Field Thermal Radiation




Definition of evanescent field thermal radiation: both nanoparticle size and particle distance are less than the evanescent wave wavelength
e)
 

Far Field, Near Field and Evanescent Field Radiative Heat Transfer


Given a temperature above absolute zero, all objects will emit electromagnetic waves, which are generated by the thermal motion of electrons and ions within the object, radiation associated with heat and light phenomena is called thermal radiation. Radiation heat transfer (far-field) occurs between objects with different temperatures. When the distance between the two objects is
equal to or less than the thermal wavelength (i.e. d"≤T), the radiation heat transfer will be significantly enhanced, meaning the near-field thermal radiation heat transfer takes place between the objects.
There are two forms of electromagnetic waves: one is propagated into free space, that is, propagating waves; the other is just propagating along the surface of the object, and the electromagnetic field decays exponentially in the direction perpendicular to the surface of the object, that is, evanescent wave.
The evanescent wave does not radiate energy to free space, but is a wave localized on the surface of the material. Only when the distance between two objects is equal to or less than evanescent wave wavelength (i.e. d"≤e), the surface wave of one object is coupled with the surface wave of the other object to enhance heat transfer, thus defining evanescent field radiative heat transfer. 

Quantum Heat Transfer


Quantum medium is composed of different types of dielectric nanoparticles. With a weight ratio of 1:100
in deionized water, the closest-packing structure between nanoparticles is self-assembled in liquid to afford a many body near field radiative heat transfer system. The quantum, size, interface, surface effects of nanoparticles and the surface phonon polaritons induced by heat couples with electromagnetic waves to afford a novel heat transfer method, which includes many body near field radiative heat transfer (particle surface distance d<λT via photon tunnelling), many body evanescent field radiative heat transfer (particle surface distance d<20 nm, via both optical and acoustic phonon tunnelling) and phonon heat conduction (when the particles are in close contact), which is defined as quantum heat transfer method.

Nanostructure in Liquid and Heat Transfer

Evanscent Field Radiative Heat Transfer

(a)Heat transfer in the deep subwavelength regime over a wide range of temperatures. Inset: the same data, on a logarithmic scale. R. St-Gelais, et al., Nature Nanotechnology volume 11, pages515–519 (2016).

(b)Measured extreme near-field thermal conductances for dielectric and metal surfaces Kim K, et al., 2015 Nature 528 387 

Nanofluid Enhances Boiling Heat Transfer


Possible mechanism

Nanoparticles deposit on the heated surface to enhance surface roughness, wettability and capillary performance, thereby increasing the nucleation site density and increasing the bubble departure frequency to increase CHF.

Experimental results

Nucleation site density and bubble departure frequency are decreased.
Heat transfer coefficient is decreased by 50%, CHF is increased by 100%
 

CHF is increased due to near field thermal radiation between the heated surface and nanoparticles.

Particle Distance Between Uniformly Suspended Nanoparticles in Nanofluid

Right Shift of Boiling Curve of Nanofluids

Nanoparticles change the features of base fluid thus right shift the boiling curve with reduced heat transfer coefficient 

[1] F. R. Dareh, et al, Heat and Mass Transfer 54, 1653-1688.
[2] C. Gerardi, et al, Nanoscale Research Letters 2011, 6:232.
[3] Z. Shahmoradi, et al, International Communications in Heat and Mass Transfer 47 (2013) 113-120
[4] A. Akbari, et al, ACS Omega 2019, 4, 21, 19183-19192

Bubble Departure and Nucleation Site Density of Nanofluids

Comparison of bubble departure frequency (a) and Nucleation site density between nanofluids and DI water (b).

Citation from C. Gerardi, et al, Nanoscale Research Letters 2011, 6:232.

Quantum Medium

Emissivity of Quantum Medium

Dielectric Constant 
Quantum Medium vs DI Water

QM is prepared with 1g of quantum medium powder mixed with 100 ml of deionized water, its dielectric constant is 260. 

Dielectric Constant 

Instrument DHR-3 (TA Instrument)

Testing Conditions25mm Parallel Plate; 
                                  Voltage=2.0 V

                                  Dielectric frequency: 10
3 ~ 106 Hz; 
                                  
Equivalent circuitParallel

 Stability of DI Water vs Quantum Medium

The stability of quantum medium is superior to deionized water

Stability of DI Water vs Quantum Medium at Elevated Temperature

The stability of quantum medium is superior to deionized water

Specific Heat Capacity & Thermal Conductivity of Quantum Medium vs DI Water

The addition of quantum media did not reduce the specific heat capacity of the base fluid.

The addition of quantum media did not reduce thermal conductivity of base fluid.

Self-Assembly Closest-Packing Structure in Liquid
 

Quantum medium is mixed with deionized water at a weight ratio of 1:100

Self-assembly of electromagnetic forces between nanoparticles and base fluid

Self-assembly closest-packing structure in liquid
(d <
20 nm)

The quantum, size, interface, surface effects of nanoparticles and surface phonon polaritons induced by heat couple with electromagnetic waves to induce quantum heat transfer method

Technical & Economic Value of Quantum Medium

Sustainable Development of Quantum Medium

Non-toxic

Inorganic nanoparticles, non-volatile, non-flammable, and non-explosive

Eco-friendly, in compliance with regulations

Comply with the most stringent environmental standards of the EU and Japan

No rare-earth elements

Metal, transition metals, non-metal oxides, abundant supply

Sustainable Development

Protection of intellectual property rights, environmental protection and energy saving. Supported worldwide.

Second-Generation Heat Pipe Technology


I. Quantum Heat Transfer

The heat pipe transfer heat via quantum heat transfer method (including many body near field radiative heat transfer, evanescent field radiative heat transfer and phonon heat conduction) coupling heat conduction and convection with significantly increased critical heat flux and reduced thermal resistance.

II. Quantum Medium

When quantum medium is mixed with deionized water, the dynamic closest-packing structure is self-assembled in liquid. The quantum, size, interface, surface effects of nanoparticles and surface phonon polaritons induced by heat couple with electromagnetic waves to generate quantum heat transfer method.

III. Quantum Heat Pipe

The outer surface has high electrical conductivity. The inner surface is considered as a component of quantum medium. This special design is to meet the requirements of quantum heat transfer method, thus enhancing heat transfer performance and reducing cost.

Heat Transfer of Second-Generation Heat Pipe

Heating Rate Comparison

 

Superheat of DI Water and Quantum Medium

 
 

Boiling Curve, CHF and Superheat

Quantum Heat Transfer

Enhance heat transfer coefficient

Left shift the boiling curve

Quantum Heat Transfer

It can be concluded that only quantum heat transfer enable the reduced thermal resistance with the increasing power.

Industry Applications

Waste Heat Recovery Application of High Temperature Flue Gas

High temperature waste heat recovery
Increase heat exchange area
Improve energy efficiency
Reduce carbon emission
Reduce operating cost

Waste Heat Recovery Application of High Temperature Flue Gas

High temperature waste heat recovery
Increase heat exchange area
Improve energy efficiency
Reduce carbon emission
Reduce operating cost

Application of Quantum Heat Transfer Technology

Quantum medium is directly mixed with deionized water at a weight ratio of 1:100 for the application of quantum heat transfer technology.
Filling process is in compliance with traditional heat pipes without sonication and surfactant.
Dynamic self-assembly of the closest-packing structures afford many-body system local field thermal radiation in liquid.

Global Patents