CN110767959A

CN110767959A - Dynamic cooling system

Info

Publication number: CN110767959A
Application number: CN201910955323.9A
Authority: CN
Inventors: 张强; 克里斯托夫·海因里希·布鲁克; 苗昕
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-10-09
Filing date: 2019-10-09
Publication date: 2020-02-07

Abstract

The dynamic cooling system of the present invention comprises: the device comprises a shell, a liquid inlet and a liquid outlet, wherein the two ends of the shell are respectively provided with a liquid supply port and a liquid outlet; the cooling island is arranged in the shell, and the inner cavity of the shell is divided into a plurality of cooling channels by the plurality of cooling islands; the control assembly is arranged in the cooling channel. Compared with the prior art, the invention has the following beneficial effects: (1) by adopting the online micro pump and the intelligent controller, the cooling fluid is controlled to directly flow to the part of the heat source which particularly needs to be subjected to temperature control, and the quick dynamic response to the sudden heat load (the common problem of CPU cooling) can be realized. (2) By providing flow pulsations (e.g., sudden accelerations and decelerations) using pumps or control valves, the pulsating cooling mode can be optimally controlled, periodically breaking the thermal boundary layer, and introducing additional turbulence generation and propagation to increase cooling efficiency. (3) Through a scanning type cooling mode, the refrigeration capacity of the cooling liquid is greatly enhanced by utilizing different time scales of fluid-solid coupling heat exchange.

Description

Dynamic cooling system

Technical Field

The invention belongs to the new energy automobile and power electronic industry, and particularly relates to a dynamic cooling system.

Background

In the computer and power electronics industries, the miniaturization of high power circuits and electronic packages of products inevitably leads to a large increase in heat flux. It is reported in the literature that a 10 ℃ increase in junction temperature typically results in a half-life reduction in semiconductor devices. In practice, electronic cooling techniques need to address not only design space challenges, but also transient sudden thermal spikes. In the rapidly developing new energy electric vehicle industry, power improvements for electric vehicles require large-scale batteries and high-current discharge. These batteries generate a large amount of heat during rapid charge and discharge cycles at high current levels. Thermal management of batteries has become a key technology to improve the performance, safety, and reliability of electrochemical energy conversion and storage systems. The urgent need of users for fast charging of electric vehicles also means that the development of efficient cooling technologies is not slow. In the aspect of green energy and waste heat recovery, the efficient heat exchange mechanism can greatly improve the efficiency of the whole system and prolong the duration of heat storage and release.

The prior art, Chinese invention patent thermal management System for controlling dynamic and steady state thermal loads (publication No. 105836138A), comprises a closed dynamic cooling loop and a closed first steady state cooling loop. Each circuit has its own compressor, heat rejection exchanger and expansion device. A Thermal Energy Storage (TES) system is configured to receive a dynamic load and thermally couple a dynamic cooling loop and a first steady state cooling loop. The dynamic cooling loop is configured to cool the TES to fully absorb thermal energy received through the TES when the dynamic thermal load is on, and the steady state cooling loop is configured to cool the TES when the dynamic thermal load is off.

In the face of these important technical demands, the conventional steady-state thermal management technology has faced development bottlenecks.

Disclosure of Invention

In view of the drawbacks of the prior art steady state cooling techniques, it is an object of the present invention to provide a dynamic cooling system that solves the above mentioned technical problems.

In order to solve the above technical problem, the dynamic cooling system of the present invention includes: the liquid-supply device comprises a shell, a liquid-supply pipe and a liquid-discharge pipe, wherein a liquid supply port and a liquid discharge port are respectively arranged at two ends of the shell;

a cooling island disposed within the housing, the plurality of cooling islands dividing the interior cavity of the housing into a plurality of cooling channels;

a control assembly disposed within the cooling passage.

Preferably, the control assembly comprises a temperature sensor, an online control pump and an intelligent controller; wherein

The intelligent controller is respectively communicated with the temperature sensor and the online control pump.

Preferably, the in-line control pump is a micro-pump.

Preferably, the control assembly comprises a temperature sensor, a valve and an intelligent controller; wherein

The intelligent controller is respectively communicated with the temperature sensor and the valve.

Preferably, the control assemblies are in multiple groups.

Preferably, surface structures are provided on the sidewalls of the cooling islands.

Preferably, the surface structure is a pit rib, a post rib or a pit.

Compared with the prior art, the invention has the following beneficial effects:

(1) by adopting the online micro pump and the intelligent controller, the cooling fluid is controlled to directly flow to the part of the heat source which particularly needs to be subjected to temperature control, and the quick dynamic response to the sudden heat load (the common problem of CPU cooling) can be realized.

(2) By providing flow pulsations (e.g., sudden accelerations and decelerations) using pumps or control valves, the pulsating cooling mode can be optimally controlled, periodically breaking the thermal boundary layer, and introducing additional turbulence generation and propagation to increase cooling efficiency.

(3) Through the scanning type cooling mode, transient centralized cooling can be realized for each independent channel, and the refrigerating capacity and the controllability of cooling liquid are utilized to the maximum extent.

Drawings

Other characteristic objects and advantages of the invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following figures.

FIG. 1 is a schematic diagram of the dynamic cooling system of the present invention.

In the figure:

1-shell 2-liquid supply port 3-outflow port

4-cooling island 5-control assembly 6-cooling channel

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

In humans, blood flow pulsations help us to keep the blood flow system healthy by periodically clearing local accumulations and intravascular recirculation. Early fluid mechanics studies also showed that the velocity profile of pulsating flow (Stokes layer) is steeper near the wall than in steady Poiseuille flow, with turbulent kinetic energy and reynolds stress increasing by an order of magnitude over equivalent steady flow. Unsteady pulsation modes have a plurality of controllable factors (such as high and low peak values, frequency, waveform, increase and decrease rate and the like) in the time dimension, and the wall turbulence design also has different geometrical characteristics (such as pits, ribs, grooves and the like) in the space dimension. Both of these changes the pressure gradient of the wall surface in transient state or local state from the basic flow mechanism, thus destroying the form and development of the fluid boundary layer and the thermal boundary layer. If the heat management technology is explored in the two dimensions, the space of the original optimization design is obviously greatly increased.

On another level, most thermal management applications involve coupled heat transfer between convective heat transfer and solid heat transfer. Conduction processes in solids are much slower compared to convection, and the difference in time scale can be up to several orders of magnitude. This also means that it is possible to optimally design the intermittent pulsating flow unsteady mode using the "buffer time" provided by the solid material to achieve enhanced time-to-time heat transfer. From the overall heat exchange effect of unsteady flow-solid coupling heat exchange, the shorter the buffering time is, the better the buffering time is, and the lower the solid heat conduction resistance is, the better the buffering time is. The heat storage capacity (heat conductivity, heat capacity, size and the like) of the solid wall material can play a role which cannot be ignored in the unsteady pulsating heat exchange process, and the solid wall material is supposed to become a design variable for the overall heat management optimization.

Compared with the traditional simple one-inlet one-outlet cooling design, the invention introduces intelligent multi-point control and realizes the accurate optimization of the pulsation mode by controlling the pump on line, thereby realizing the most efficient cooling effect.

Based on the principle, as shown in fig. 1, the dynamic cooling system of the invention comprises a multi-channel assembly (comprising a shell 1 and a cooling island 4, wherein a liquid supply port 2 and an outlet port 3 which are communicated with an inner cavity are respectively arranged at two ends of the shell 1) and a control assembly 5 (comprising a temperature sensor, a plurality of online control pumps and an intelligent controller). The multi-channel assembly is mounted on a heat source and heat is removed from the heat source by a heat transfer fluid flowing through a single or multiple cooling channels 6. A plurality of temperature sensors are used to collect temperature data associated with the heat source. One way to implement an on-line controlled pump is a micro pump commonly used in biomedicine. The controller dynamically optimizes and controls the output action of the pump according to the feedback temperature data, and high-efficiency pulsating cooling is realized. The temperature sensor and the in-line pump assembly may be integrated with each other, optionally in a single channel.

Furthermore, a 'scanning type' pulsation mode is realized by opening and closing a valve in dynamic control. Unlike conventional designs that evenly distribute the cooling grid liquid, the present invention injects only a subset of the total number of coolant channels (each channel being a channel through which the heat transfer fluid flows) at a time, such as only one channel at a time. By selecting the appropriate sweep frequency, the Reynolds number of the fluid for each channel can be multiplied instantaneously. The thermal boundary layer can also be periodically broken up by high amplitude pulsations (sudden acceleration and deceleration). This scanning process introduces additional turbulence generation and propagation. The design effect of the second structure is illustrated by numerical calculation. In conventional steady state cooling designs, the inlet section is relatively overcooled due to the development of a thermal boundary layer, while the rear region is relatively undercooled. For the same overall cooling flow, the potential benefits of the sweep cooling of the present invention: due to the aforementioned physical mechanism, a more uniform cooling performance can be obtained. The sweep frequency and pattern become additional control parameters that improve overall thermal performance.

Still further, surface structures, such as pit ribs, column ribs, pits, and the like, are added to the cooling channels of the first structure and the second structure. An example of a typical pit surface design temperature field. Although the enhancement can be achieved entirely by this surface design, the low momentum coolant circulating in the pits ("dead coolant") becomes an important factor in local thermal performance. By introducing high amplitude pulsations, the formation of flow recirculation (hot fluid) can be disrupted and flushed from the walls. The physical principle behind this is very similar to the mechanism by which pulsating blood flow in a healthy person excludes vessel wall residue. The traditional pit surface design is combined with scanning cooling, and the whole convection heat transfer can be obviously improved by controlling the pulsation mode of the cooling flow.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.

Claims

1. A dynamic cooling system, comprising:

the liquid-supply device comprises a shell, a liquid-supply pipe and a liquid-discharge pipe, wherein a liquid supply port and a liquid discharge port are respectively arranged at two ends of the shell;

a control assembly disposed within the cooling passage.

2. The dynamic cooling system of claim 1, wherein the control assembly includes a temperature sensor, an online control pump, and an intelligent controller; wherein

3. The dynamic cooling system of claim 2, wherein the in-line control pump is a micro-pump.

4. The dynamic cooling system of claim 1, wherein the control components include a temperature sensor, a valve, and an intelligent controller; wherein

5. The dynamic cooling system of claim 1, wherein the control assemblies are in a plurality of groups.

6. The dynamic cooling system of claim 1, wherein a surface structure is provided on a sidewall of the cooling island.

7. The dynamic cooling system of claim 6, wherein the surface structure is a dimpled rib, a stud rib, or a dimple.