a new car during the development phase must take into account the various climatic phenomena it may encounter, so it is necessary to place the vehicle in the corresponding reliability test, but by which some day eat imply. We need the climatic conditions are often not the people’s will, it can simulate various weather conditions of the vehicle may encounter real-life situations through the establishment of a small Earth-like environment, and this is the so-called man-made global environment thermodynamic wind tunnels.
● and the difference between the aerodynamic wind tunnel
I believe many people heard the wind tunnel, but depending on the test objects and purposes, can be divided into tunnel are many, the most common is kinetic wind tunnel, which is mainly used to design and optimize the aircraft, missiles, spacecraft exterior styling, dynamics in the wind tunnel can simulate conditions as they may arise in the high-speed movement.
For automobile manufacturers, the wind tunnel to develop aerodynamic body shape also plays an important role, especially in some supercar manufacturer. Engineers typically will first be made 1: 1 clay model of the car, and then tested in a wind tunnel, a strong air flow generated by the blowing wind tunnel body surface to observe the flow of gas meets the needs of the design, then again details modified to meet the requirements that the drag coefficient.
Of course, you can build into a 1: 1 scale model wind tunnel car price is not cheap, often reach hundreds of millions of dollars or even more, and to do every time the wind the cost of the test hole is quite large.
Further thermodynamic wind tunnel is a noun, its main purpose is to simulate a variety of road vehicles encountered in practical situations, climate change, it can simulate rain and snow, different temperature and humidity environment. However, you do not need these aerodynamic wind tunnel, it only needs a hair, which is the biggest difference between the two.
Below is located in Shanghai Pan Asia Technical Automotive Center thermodynamic wind tunnels described as an example
● fan weight 40 tons maximum wind speed of 250km / h [ 123]
This thermodynamic tunnel located in Shanghai PATAC, building has a main test chamber, a pre-test chamber, fan, duct, cooling / heating system, chassis dynamometer, sunshine simulation / snow simulation system, data acquisition systems.
by weight of the core components of the fan in the tunnel of 40 tons and a maximum speed of 708rpm, although speed is not high, but since the fan diameter 3.6 m, so at full speed with duct design, the outlet may be generated in the final speed of 250km / h wind, power of the motor at a time of 1500kW.
To produce high quality and controllable air, duct design is of quite particular. Viewed from the side, the entire duct using ldquo; Press rdquo; shaped structure, weighs 70 tons, the vertical arrangement of such a manner that the vertical drop duct reached 9 m. Layer 3 of the building of the wind blowing fan duct diverging section will reach the ground floor through a long duct, its main function is to allow the buffer stream obtained here, rectified and then finally through the constriction 7 from a square meter main blow outlet quick test module.
from the fan to the air outlet with a long distance, so when the fan speed changes, the wind speed is bound to the outlet delay, but this delay is of within 5 seconds. Outlet has an area of seven square meters, in fact it can be reduced to five square meters, by adjusting the outlet area, may be highest wind speed in the wind tunnel immediately upgrade from 200km / h to 250km / h. This kind of wind tunnel design ldquo; preoccupied rdquo; to ensure that the trial closer to or equivalent to the real situation.
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main test chamber to simulate -40 to 60 degrees Celsius climate and weather conditions to achieve rain and snow
Main JEM used to place the test vehicle, with a chassis dynamometer mounted on the ground. It can be in vain if the vehicle car, drive wheel rotation, while simulate different road friction coefficient of the road facing the load generated by the vehicle, which is realized in the test compartment of the vehicle running state of the real situation.
In such a length of 22 meters, 9 meters wide, 6.6 meters high main cabin experiments, also equipped with a lighting system and a system of rain and snow. Lighting system which can simulate a variety of angles and light intensity of sunlight in different parts of the world the reality of the time period in the morning, afternoon, evening and so on, up to 1,200 watts / square meter, more than the world’s highest sunshine intensity there are statistics mdash; mdash; 1000 W / m.
Winds system through the compressor and pump snow implemented to meet the needs can completely reproduced in the case of a vehicle moving in a natural snow conditions. JEM main compressor can achieve a temperature change from -40 degrees to 60 degrees, the temperature change rate of 0.6 ℃ / min, faster temperature changes in a day can be achieved under test extreme heat and extreme cold two cases, while more realistic simulation of climate change.
●
thermodynamic models developed in the wind tunnel significance
In the absence of thermodynamics wind tunnel test vehicle is to see the face of God, but also by a lot of interference. In four seasons in China, only a year, winter or summer, both the northern and southern hemispheres, but also take advantage of the two. For example, in doing high-temperature test vehicles or air-conditioning system testing, then it needs 7-8 months in China, in December, January and Australia, and with the wind tunnel, the unlimited external conditions, year 12 month can take advantage of a small simulation debug environment for the development of the vehicle. Imagine, research and development costs or whether it is time to get better control, greatly improving the work efficiency.
Of course, also the wind tunnel is not a panacea, even with thermodynamic tunnel, nor will all tests completed in a wind tunnel, which is usually used to complete the work of 80 percent, while the remaining 20 percentage of the actual condition will need to pre-final inspection down in the wind tunnel results.
has more than 2000 channels in this thermal wind tunnel, that is, each of an information data channel, the data acquisition by measuring, Analysis, can be the vehicle under various conditions to capture feedback out of the situation was more sensitive, detailed and technical personnel to help identify more precisely the crux of the problem.
Summary:
dare to imagine, if we hold the prehistoric climate data, it is entered into the computer simulation and the wind tunnel by thermodynamics, and then look at modern industrial civilization the product mdash; mdash; car, is suitable for use as a master of the Jurassic and Cretaceous age in the dinosaurs, but that’s just our ideas are like imagination and wishful thinking. Can be reproduced in different climatic conditions around the world through thermodynamic wind tunnels, homes can be simulated on the test vehicle. Looking at the well-known auto companies worldwide, thermodynamic wind tunnels is already an integral part of modern research and development facilities, but it does reflect the strength of car prices in the technology and product research and development.