First aid. Graduation project 2 10kw automotive air conditioning compressor performance test electr

The automotive air conditioning system consists of two components: the refrigeration system and the electrical control system. Strictly speaking, the air supply system should also be included, but in small and medium-sized cars, most of the air supply tasks of air conditioning are directly completed by the evaporation tank.

The refrigeration system consists of a compressor, a condenser, a liquid reservoir dryer, an expansion valve, an evaporator, a fan, an air inlet hood and a refrigeration pipe. For the whole air-conditioning structure (including cooling, heating and ventilation), a heat exchanger (warm air core) is placed in parallel with the evaporator to play the role of heating. Engine cooling water is used as the heat source for heating.

The electrical control part includes power switch, electromagnetic clutch (most small and medium-sized vehicle compressors are equipped with electromagnetic clutch), fan variable speed switch and resistor, various temperature controllers, high and low pressure switches, speed control devices, and various relays. In the past ten years, many high-end cars have gradually adopted computer automatic control, which has greatly reduced the trouble of manual adjustment and improved the economy and effect of air conditioning.

The air conditioning compressor of small and medium-sized cars is powered by the main engine of the car, and the start and stop of the compressor is determined by the electromagnetic clutch, and the automatic control electromagnetic clutch works with various temperatures, pressures, and speeds as the control switch with induction signals, for example, if the surface temperature of the evaporator is too low, it is easy to cause frost on the surface and affect the refrigeration effect, so it is equipped with a temperature controller (thermostat). The surface temperature of the evaporator is used as a control signal to control the clutch of the electromagnetic clutch, if the temperature of the compressor head is too high, the high-pressure part will be damaged due to the abnormal increase in pressure, so it is equipped with an overheating switch or pressure switch. If the system is deficient in refrigerant, it is possible that the refrigeration oil is also lacking.

If the compressor is operated under this dry friction situation, it is easy to be damaged, so the electromagnetic clutch also accepts the switch signal of the low pressure of the depressurized part and automatically protects the compressor from starting.

For the computer-controlled air conditioning system, the start and stop of the compressor (or the opening of the heating air and water valve) can meet the various cooling and heating conditions required by the air conditioning system in the most economical state.

In order to solve the problem of power matching and water tank cooling under operating conditions such as idling and acceleration of the car, the method of aborting the operation of the compressor was often used in the past, and the method of increasing the idle speed has been adopted more recently.

In addition, the automobile air conditioner should meet the needs of sending cold air or hot air or fresh air to the head, feet, left and right directions of the occupants, as well as sending cold and hot air to defrost and defogging the windshield, and there is a more complex valve control system.

1. Compressor.

The compressor of the air conditioning system sucks in the refrigerant from the suction valve during operation, and discharges it from the exhaust valve after compression. Its principle is similar to that of ordinary air compressors, but the requirements for sealing degree are higher than those of air compressors. The compressor comes in the form of:

Crankshaft piston compressors (parallel twin cylinders, V-twin cylinders), swash plate piston compressors, rocker piston compressors, rotary vane compressors, etc.

1. Crankshaft piston compressor.

This type of compressor compresses the gas by changing the volume, and there are two types: vertical and horizontal. The principle is the same as that of a piston engine, but the compressor is a pump, which is the opposite of an engine.

Simplicity and practicality are the basic characteristics of a modern minimalist style. The minimalist style has been popular for several years and still maintains a strong momentum, because people always want to reflect a certain cultural taste while decorating economically, practically and comfortably. The minimalist style not only pays attention to the practicality of the room, but also reflects the delicacy and personality of the life of the industrialized society, which is in line with the life taste of modern people.

Decorative elements: metal lampshades, glass lamps, high-purity colors, furniture with simple lines, soft furnishings in place.

Metal is a product of industrialized society and the most powerful means of embodying a minimalist style. A variety of metal lamps of different shapes are representative products of modern minimalism.

The space is simple, and the colors have to jump out. The use of high-purity colors such as apple green, dark blue, bright red, and pure yellow is bold and flexible, which is not only a follow-up to the minimalist style, but also a display of personality.

Emphasizing functional design, simple and smooth lines, and strong color contrasts are the hallmarks of modern style furniture. In addition, a large number of new materials such as tempered glass and stainless steel are used as auxiliary materials, which are also common decorative techniques for modern style furniture, which can bring people an avant-garde and unrestrained feeling. Due to its simple lines and few decorative elements, modern furniture requires a perfect soft fit to show off its beauty.

For example, a sofa needs cushions, a dining table needs a tablecloth, a bed needs curtains and sheets, and soft furnishings are the key to modern furniture decoration.

Study plan.

Learning: 1. Listen carefully in class, do not desert, and develop good study habits. 2. Carefully preview before class, so that you can roughly grasp the knowledge you have learned before the start of class.

3. After class, carefully review the notes made in the lecture and review them together, do more practice questions, and do it well, can do it, and do it quickly. 4. Make a corresponding study plan every day, develop a good habit of getting up early, and do an appropriate amount of exercise every day, so that the body can progress with learning. 5. Ask the teacher questions that you can't do, don't give up, and learn practically, skillfully, and finely.

6. Be able to complete homework on time, accept the teacher's criticism with an open mind, and not have a sense of resistance.

Poor student counseling: 1 For students who are very self-motivated, study hard but have unsatisfactory grades, you can find a few students in the class to give a speech on learning methods, impart learning experience, so that they have rules to follow and do not take detours. 2. For those students who do not want to learn, psychological counseling should be carried out to change their views on learning, and let them know that current learning is the main way out.

3. It is best to transfer the students with better academic performance and the students with poor grades who love to study at the same table, so that they can make progress together.

Improve academic performance: 1 First of all, study hard, take notes often in class, review before class, and don't know how to ask the teacher. 2. Truly integrate into the big family of the class, exchange experiences and learning methods with classmates, and discuss problem-solving skills.

3. Increase your interest in learning, whenever interest is the key. 4. Learn more by yourself, practice more, and summarize your own methods, which will make learning twice the result with half the effort. 5. For subjects that you don't have a clue about, you might as well ask the teacher to give you guidance.

I have listed the specific methods, I hope to give you some help, and finally I wish you success in your studies and early success.

It depends on your own personal situation

Let's make a periscope, two flat mirrors parallel to each other, both at 45 angles to the horizontal plane, as in the book.

Uh, let's talk about the stupidest thing, two disposable paper cups, connected by a thread, are the legendary **

I suggest, please don't be surprised:

The difference between AMD240 and 245 is only 5-10 yuan, and it is recommended to change it to 245

2.The memory basically wants to develop above DDRII1066, and the DDRII1066 of Kingston 2G is cheaper than your 800, so 800 is not recommended

3.If you use Western Digital for hard drives, don't buy 8m, you want 32m, and your 320g is a bit small for now, 320g costs 335 yuan, and 500g is 355 yuan, buy more 180g with 20 yuan, I think this is more affordable, if you want to buy cost-effective, you can consider Hitachi, if you want quality, buy Seagate.

4.There is no need to go to 400W, after all, yours is a centralized display, if you want to add a separate display in the future, buy a power supply rated at 350W, the maximum 400W, which saves money.

Overall, your setup is okay, and if you don't plan to play high-end games, you can use it for a while! If you can, follow my suggestion above, add a few dozen dollars, then your configuration should be better!

The CPU Athlon II*2 240 has been discontinued.

Let's go up to 245.

There are also more Kingston fakes, for Weigang.

CPU: AMD Athlon 11x2 245 410 Motherboard: MSI 785TM-E45 499

Memory: Kingston 2G-DDR2800 280

HDD: WD320G 300

Display: AOC19" 850

Optical drive 120

Chassis + Power Supply: ADX+P400W 280

It's just an estimate, and there must be an error.

CPU to 245, 245 is more cost-effective than 250, the power supply is not so big, it is enough to change to a rated 300W, within 200 yuan, which can save some money.

CPU: AMD II X245 (about 399) Motherboard: Onda A785G+128M (Magic Flute) (about 470) memory with DDR3 1066 2G (about 240) hard disk:

WD 500g (around 340).

The display does not change (around 890).

Chassis + power supply: ADX+P400W (about 240) is estimated to be more than 2700. Because the price changes at any time, that's about the price.

Personally, I have already helped people with two units. The overall performance is quite good, and it is no problem to cope with large 3D motherboards, which come with 128M independent video memory.

……How to say it. It's good, but it's also average on the market now. That's it.