As early as during his study in Hujiang University, Zhang Guotao began to engage in the research of molecular physics, and achieved initial results. 1930, he published the paper Physical Constants and Molecular Forces, and put forward the equations of state of liquids and solids.
P-k (v-v0)/v0 = rt/(v1v0) This was original at that time.
On this basis, in 1936, Zhang Guotao published two papers, calculating atomic radius from compression coefficient and expansion coefficient and calculating molecular radius from compression coefficient and expansion coefficient, and put forward a new method to calculate atomic radius and molecular radius in liquid state by using compression coefficient and expansion coefficient, and used this method to calculate more than 20 kinds of solid alkyl molecules and benzene with the length of 1 1.
Zhang Guotao's master thesis "Theoretical Properties and Mechanism of Liquid Molecular Aggregation" entered the study of liquid aggregation. At that time, this work played a certain role in the study of liquids. Since then, his research work has turned to fluid mechanics.
In fluid mechanics, the study of turbulence has always been a "long-standing problem". It is called "Lao" because this problem has been studied for nearly 100 years; It is said to be "big" because turbulence is the most common flow in fluid mechanics and the most important problem; It is said to be "difficult" because although countless famous scholars have studied it in the past hundred years, the problem has not been solved so far.
At that time, a school of scholars thought that the main problem was that it was difficult to solve the Naville-Stokes equation (N-S equation for short) mathematically, so the key was how to solve the N-S equation under turbulent conditions.
Zhang Guotao disagreed with the above view. He believes that turbulence cannot be studied because the physical mechanism of turbulence is not clear. In order to establish new equations, he insisted on studying the physical nature of turbulence. Since 1933, when he was a Ph.D. student in the United States, Zhang Guotao began to study the theory of turbulence of fluid mechanics and its application. 1935 Ph.D. thesis "falling objects in the flow and its influence on turbulence" studies the state of falling objects after falling into the fluid and its influence on turbulence. This achievement was later cited by people who studied fluidization. For example, this achievement is mentioned in D.F. Othmer's book on fluids, which is considered as the earliest study on the interaction effect of monomers carried by fluids. Before and after the founding of the People's Republic of China, Zhang Guotao was mainly engaged in the research on the basic theory of turbulence, and he had many original opinions. During this period, he published a lot of papers, among which the article "Thermal Theory of Turbulence" compared turbulence with molecular thermal motion, put forward the analogy concept of turbulent temperature, and calculated some problems, and obtained the results consistent with the experiments. Since then, papers such as "A Turbulent Motion Equation" and "On Turbulent Resistance" have been published. On the one hand, these papers demonstrate that the N-S equation cannot be used in turbulence, on the other hand, they put forward their own equations and their solutions, forming a unique academic point of view. Some of Zhang Guotao's academic thoughts and research achievements have been quoted by internationally renowned scholars who study turbulence in their works. Some are similar in ideas.
Zhang Guotao devoted himself to the study of theory of turbulence, and paid special attention to applying this theory to solving practical problems in China.
194 1 year, Northwest Academy of Sciences was established, with Zhang Guotao as a researcher. He combined a very serious problem of the northern desert moving south in China at that time to study sandstorms. He analyzed the movement of sand particles carried by the wind from the viewpoint of fluid mechanics, and wrote the article "The Problem of Desert Moving South in Northern China", which put forward scientific arguments for the expansion of desert under the action of wind and called for controlling the expansion of desert. This paper won the paper award of the Engineering Society at that time. However, in the old society, this problem was not taken seriously and solved at all. After the founding of the People's Republic of China, the Party and the government attached great importance to the southward migration of the northern desert, and built windbreak and sand-fixing forests on a large scale, which achieved remarkable results.
1964, Zhang Guotao was the president of Tianjin University. At that time, China formulated a ten-year science and technology plan, in which one of the central topics of the mechanical part was theory of turbulence's research. Zhang Guotao is the academic leader and project leader of this project, and also attaches great importance to its applied research. Tianjin University is an engineering school. Zhang Guotao believes that engineering schools should solve practical problems in engineering technology. Such as pneumatic conveying and fluidization. He also named these research contents "particle-fluid mechanics", and he believed that the research results in these aspects could be immediately used in production, which promoted the development of production. Twenty years later, the international research in this field developed vigorously, which proved Zhang Guotao's foresight.
To engage in applied research, we must first grasp the experimental work. Zhang Guotao said: Before the founding of the People's Republic of China, there were no conditions for experiments, so most of the older generation engaged in theoretical research. They have to learn theory when studying abroad, because they have no conditions to do experiments after returning home. In this way, foreigners experiment in the East, and China's theory follows in the East; The experiments of foreigners are western, and China's theory is western. In this way, China people's scientific research cannot be independent, and it has a semi-colonial color of relying on foreign countries. Now that China is politically, economically and militarily independent, so should our scientific career. To be independent in science, we must first establish our own experimental base. Therefore, we must make up our minds to grasp the experiment and think about this problem from a big perspective. That's how he knew, and that's how he tried to practice with his own actions.
Zhang Guotao's research on theory of turbulence and its application lasted for nearly 30 years. Even in the case of extremely heavy administrative work and frequent social and political activities, he still used all available time to make unremitting research and exploration. Academic circles praised his serious scientific attitude and persistent dedication. Qian Weichang said: "Comrade Zhang Guotao is an honest scientist. He is serious and diligent, and has done a lot of work in theory of turbulence. He is admired by his contemporaries and deserves to be a model for young people. " Zhang Guotao is a patriotic intellectual. 193 1 year, Zhang Guotao left home to study in the United States. When he left and boarded the ship, he wrote a sentimental poem, which read:
The three cities invaded the sea, and the pavilions were full of fish and shrimp.
The northeast invaded and the frontier was unguarded.
What do men want? Learn from Dayu.
He expressed his heavy feelings of worrying about the country and the people and his ambition to return to China to serve the motherland after his studies. In my autobiography, Zhang Guotao described the infuriating things he encountered during his study in the United States: just arrived in the United States, on the way to Chicago by train, he was mistakenly arrested by the police and detained for one day for no reason; During the September 18th Incident, Chiang Kai-shek gave up the Northeast because he did not resist the policy, so he was ridiculed by American professors. He deeply felt that China people were despised and bullied everywhere because his country was not strong. In order to express his indignation, Zhang Guotao wrote his name with the esperanto pinyin "DjangGwoh-Fan" instead of English. China students from his university in Iowa also transliterated Iowa as "China who loves me" to show their love for China. Zhang Guotao recalled: "These practices seem naive now, but they reflect the patriotic thoughts of young people in China at that time."
Later, under the fire of War of Resistance against Japanese Aggression, Zhang Guotao returned to the motherland. At that time, he was engaged in teaching and scientific research in the rear, but the disaster of the country and the suffering of the people called him. During the December 29th Movement, he participated in the activities of "Salvation Society". 1944, Zhang Guotao participated in the establishment of the "Chinese Scientists Association", carried out the propaganda activities of persisting in the war of resistance and opposing surrender, and served as the leader of the Association for Science and Technology of Northwest Institute of Technology.
From 65438 to 0947, Zhang Guotao participated in the "Anti-Hunger and Civil War" movement of Beiyang University. When marching in the streets, Zhang Guotao wore a gown and glasses with a nose bridge, and walked at the front of the procession with progressive students. Zhang Guotao, together with the teachers and students of Beiyang University, launched a movement of refusing to accept American aid and relief, which showed the national integrity of China intellectuals.
On the eve of Tianjin's liberation, Zhang Guotao was entrusted by the underground party organization to do everything possible to protect the progressive students, which frustrated the plan of the Kuomintang government to coerce Beiyang University to move south. When People's Republic of China (PRC) was founded, Beiyang University was temporarily in charge. Zhang Guotao not only served as a professor and director of the aviation department, but also served as the provost, actually presiding over the work of the whole school, and soon restored the teaching order of the school. 195 1 year, Zhang Guotao was transferred to the post of President of Jingu University. 1952 When the departments of China were adjusted, Beiyang University was renamed Tianjin University and Zhang Guotao was appointed as a professor. He served as vice president and president successively, and made great efforts for the construction and development of Tianjin University.
In addition, Zhang Guotao has held many social posts. 1950, jing wong, Mayor of Tianjin, and Huang Songling, Minister of Culture and Education of the Municipal Party Committee came forward to urge him to be the director of Tianjin Education Bureau. 1956, concurrently deputy mayor of Tianjin; He also served as the representative of the first, second, third and fourth China Municipal People's Congress, the chairman of Tianjin Science and Technology Association, the vice chairman of CPPCC, the Standing Committee of NLD Central Committee and the chairman of NLD Tianjin Municipal Committee.
Zhang Guotao is conscientious and proactive in all his social activities. He is thoughtful and creative. In the work of leading NLD, he is good at combining the party's United front policy with the reality of NLD in party member, and puts forward an argument that intellectuals can easily understand and accept. For example, he proposed: "NLD's organizational life should cultivate the atmosphere of' meeting friends with literature and helping others with kindness'." What he said is business, and benevolence is thought. He advocates making friends through business, helping each other and making progress together.
During the Cultural Revolution, Zhang Guotao was devastated and persecuted, depressed and his health went from bad to worse. 1975 65438+February 5, died of myocardial infarction at the age of 70.