What Zhao Guoyang said is not just arrogance, but even an arrogant one.

Not to mention Mo Xiaotian, even Zhu Maotao felt a little incredible after hearing this.

Mo Xiaotian smiled instead of anger and said, "Oh, Section Chief Zhao, please give me some advice. I, Mr. Mo, listen carefully."

Zhao Guoyang said "um" and pointed to the book and said bluntly: "First of all, I think it's very inappropriate to share this question with Researcher Zhao."

"You senior brother should know that she is just a graduate student now. She doesn't know much about vehicle performance and her thoughts are limited. It's really hard to ask her to try to solve such problems."

After Zhao Guoyang finished speaking, Zhao Siyan looked at her teacher Zhu Maotao in surprise.

In fact, when Mo Xiaotian shared this topic with Zhao Siyan, Zhu Maotao also said similar things.

However, because of Zhao Siyan's proactive request, he finally reluctantly agreed.

But Professor Zhu also had some words first, and only allowed Zhao Siyan to try to conceive some ideas, not to get into it too deeply, and she was afraid that she would get stuck in and couldn't get out in the end.

Zhao Guoyang did not notice the strangeness between Zhao Siyan and Professor Zhu, and continued to talk: "Brother Mo, your topic is a kind of extension of 'nvh'. Put it in the specific examples of the comparison between the capital Jeep and Songjiang Santara..."

"nvh?" Mo Xiaotian looked at Zhao Guoyang with a blank expression, as if he had never heard of this term.

Jiang Hong, Liu Renhe, and Liu Yaohong also looked at me, and I looked at you, all of them were confused.

Only Wang Ziqing and Zhu Maotao were shot in their eyes when they looked at Zhao Guoyang.

Especially Zhu Maotao, he looked at Zhao Guoyang as if he had discovered a new continent.

Seeing the confusion on Mo Xiaotian's face, Zhao Guoyang was stunned for a moment, and then realized that the term "nvh" was only spread from Western countries in the late 1980s, and it has not become popular in China.

Mo Xiaotian didn't know, it wasn't strange.

"The so-called nvh is the English abbreviation (noise, vibration, harshness) of the three nouns: noise, vibration, and sound and vibration roughness"

"This is a comprehensive question of measuring the quality of automobile manufacturing. It gives car users the most direct and superficial feeling."

"According to the current development trend, the NVH issue of vehicles has become one of the concerns of major vehicle manufacturers and parts companies in the international automotive industry. In the future, as people's requirements for automobile comfort continue to increase, their importance will be further improved."

Zhao Guoyang looked calm and explained politely, as if he was back to the time he was speaking at major seminars in the past.

"I believe Researcher Mo should also know that there are usually various data indicators to evaluate the performance of a car. For example, the power has the highest speed, acceleration time and maximum climbing level; the economy has fuel consumption of 100 kilometers, car maintenance costs, etc. So how to evaluate the comfort of a car?"

Zhao Guoyang saw Mo Xiaotian stunned and continued with a smile: "From the perspective of 'nvh', as long as the car can ensure that the noise, vibration and impact environment impact on the occupants are within a certain limit during driving, so the comfort is mainly evaluated based on the occupants' subjective feelings."

"But, the problem lies here. Due to the differences in mental and physical fitness of each person, their sensitivity to 'nvh' is very different."

"To put it bluntly, it's like aesthetics. Different people's views vary greatly. Sometimes, the appearance of a car that you think is very ok, but in the eyes of another person, you just think it's not possible."

"In addition to the differences in sensitivity of each person, we also need to consider the differences in each model. For example, a sports car must hear the roar of the engine to have a sense of control; while an off-road vehicle must feel its strong sense of collision before it is favored."

"So for the 'nvh' issue, there are different requirements for different models, which brings difficulties to the early design."

When Zhao Guoyang talked about this, everyone was already focused and did not breathe, for fear of missing such a wonderful commentary.

Even Zhao Siyan, who had been disliked by him, held her cheek with both hands and stared at him with big watery eyes.

Zhao Guoyang opened the thermos, drank a sip of water, moistened his throat and continued: "Then, it's like this defense question. The question is to analyze the performance differences between the Beijing Jeep and the Songjiang Santana."

"You list this simulation optimization model and analyze the comparison of climbing capabilities, speed and comfort between Beijing Jeep and Songjiang Santara. Is this wrong? Yes! But it's not comprehensive and objective? Then it's hard to say."

"To give a simple example, if the Beijing Jeep drives on flat ground and highway, the comfort is definitely not as good as Santala, but if you drive it in the Gobi, beach, or mud, it will definitely be better."

"In this regard, there is no comparison between the two at all! So what is the significance of your simulation model?"

Zhao Guoyang gently tapped the table and said, "In fact, simulation optimization is essential in the development process of a car model. To a certain extent, it can greatly reduce the cycle of automobile development."

"Taking the strength optimization of ordinary structures as an example, if we know that somewhere is insufficient in the simulation results, then we can immediately think of changing materials, adding reinforcement ribs, optimizing the structure, etc. to solve the problem. This method can effectively and accurately improve the body structure. At present, the matching rate between simulation and actual measurement is quite high."

"But in terms of nvh, although it has a series of methods such as simulation, vibration test and vehicle vibration test to test, it has never been able to obtain accurate and objective conclusions."

"Most of the time, the simulation results are far from the actual measured data, and it is difficult to reduce costs and production cycles."

"So, in my opinion, your subject has been wrong from the beginning!"

Zhao Guoyang's last words were like a thunderclap on the ground, shocking everyone present.

Zhu Maotao resisted his excitement and asked word by word: "Xiao Zhao, if you came to defend, how would you do this topic?"

Zhao Guoyang was just talking and didn't pay attention to the expressions of the people around him. At this time, he heard Professor Zhu's question, so he naturally could not neglect. He quickly stood up and expressed his opinions.

"Professor Zhu, if I were to solve this problem, I would not build a simulation and control system, but instead work hard on the after-sales service of the two cars, Songjiang Santara and Jingcheng Jeep..."

"First of all, I will select several common problem feedback from the after-sales feedback of these two cars. Then, based on the solutions of these problem feedback, a data comparison table will be listed."

"This table has vertical comparison and horizontal comparison. Vertical comparison means the comparison of the feedback information of the same model from the user before and after the problem is solved; horizontal comparison means the comparison of the handling of two models and similar problems..."
Chapter completed!