Abstract: Taking a disk-type valve as the object, the using the well-known exponent relationship between flow in valves and its opening angle and combining fluid mechanics on the relationship among the flow and pressure difference, the valve pipe area, the flow coefficient, then the exponential relationship between flow coefficient and its opening angle is established, under the condition of the pressure difference and the valve pipe area without variation, The two exponential relationships are the same shape, their difference lies only in the different scales, which is the characteristics of this paper. Then the actual numerical relationship among flow and valve opening angle, the pressure difference, the valve pipe area can be got to design a suitable minimum radius of disc valve pipe. Then the relationship graphs of different valve radius with valve opening angle and pressure are calculated and draw out, using different flow coefficient a. Also studied both of the static force and the impact force of the water flow with its open angle on the valve disc. The results of calculating these two forces by different formulas show that the impact force at the maximum opening angle is equal to the static force, so theoretically, a = 0,7 is confirmed as a limit of the flow coefficient, because there is a relationship of 2a2 for both forces. At last, strength of the disk shaft and its sleeve are verified too.Abstract: Taking a disk-type valve as the object, the using the well-known exponent relationship between flow in valves and its opening angle and combining fluid mechanics on the relationship among the flow and pressure difference, the valve pipe area, the flow coefficient, then the exponential relationship between flow coefficient and its opening angle is e...Show More
Abstract: Water source heat pump with relatively stable surface water as heat transfer medium is a new type of energy-saving and temperature-regulating equipment. Its refrigeration and heating coefficients are 3.5-4.5 high. Water source heat pump has been widely used in refrigeration and heating of buildings in many foreign countries as an important energy-saving equipment. The number of water source heat pump energy stations has increased by 10% annually. The traditional coal pans used in large greenhouses in China often have some problems, such as low thermal efficiency, high energy consumption, high pollution and difficult cooling in summer. It is very helpful to use water source heat pump technology reasonably to solve these problems. In this paper, the water source heat pump air conditioning system is used in public places for experimental testing and research. The operation performance of the water source heat pump energy station is studied through experimental tests, which can provide reference for the popularization and application of the technology in hot summer and warm winter areas. The research contents of this subject are as follows: Under the rated operating conditions of the water source heat pump air conditioning system ; the operation performance of the heating system is analyzed; Understanding and mastering the operation performance of water source heat pump air conditioning system, and comprehensively analyzing the stability and energy efficiency ratio of the system; The main problem to be solved is that it can not only ensure the operation cost unchanged or even reduce, but also improve the heating efficiency of water source heat pump air conditioning system.Abstract: Water source heat pump with relatively stable surface water as heat transfer medium is a new type of energy-saving and temperature-regulating equipment. Its refrigeration and heating coefficients are 3.5-4.5 high. Water source heat pump has been widely used in refrigeration and heating of buildings in many foreign countries as an important energy-s...Show More
