Research On The Rotor Of LG20T Type Twin Screw Compressor

With the development of high performance grinding machine, the screw rotor profile design becomesthe main factors that hindering the development of the screw compressor. According to the development ofthe profile history of the screw compressor, all the efficient and successful development of the efficientand successful new profiles is on the basis of the original outstanding profiles.In order to obtain andmaster the main technology of screw compressor, it is necessary for the screw compressor rotor to bestudied.Taking the LG20T type screw compressor rotors as the research object, the male and female rotorprofile was discretized, and the data points are smoothed using the standard Gaussian method to eliminatediscretization error; The nature and preliminary control parameters of the male and female rotor curvesegments are identified by practicing. The mathematical relationship between the curve and its envelopewas deduced. The accurate control parameters of curve segment are identified by comparing the calculatedenvelope with the original data points. The error between the profile equation and the origin data is foundless than0.001mm.The contact line length of Screw compressor is an important indicator to measure the performance ofscrew compressor rotor, the original calculation method to calculate the contact line of screw compressorrotor is poor universality and complicated. In this article, a3-D discrete screw compressor rotor’snumerical model was constructed and the coordinate relationship of the contact data on the female andmale rotors is the criterion to check out whether the points of the male or female rotors belong to thecontact line. The length of the contact line is calculated by summing all the length between the adjacentpoints. Taking the LG20T type screw compressor rotor as an example, respectively, using the proposedapproach in this article and the method of the referred literature to calculate the contact line length, it isfound that the relative error between the two kinds of calculation methods is less than0.2%.There is a great influence of adiabatic efficiency and power consumption for screw compressoron the triangle leakage.The relationship between the pressure difference on both sides and mass flow ratethrough the leak triangular is wanted to be found out. In this paper, the volume changing rule between the female and male rotor is calculated in numerical method. The pressure changing rule is modeled based onthe volume changing rules. A3-D model of leakage triangle was built to model the mass flow rate throughthe leakage triangle by taking the pressure changing law as the inlet and outlet pressure boundaryconditions. The relationship between the mass flow rate and the pressure difference is obtained and found aquadratic curve relation.