Modeling of Isentropic Coefficients Used in One Dimensional Model to Predict Ejector Performance at Critical Mode

  • سال انتشار: 1401
  • محل انتشار: فصلنامه انرژی و محیط زیست ایران (ایرانیکا)، دوره: 13، شماره: 2
  • کد COI اختصاصی: JR_IJEE-13-2_002
  • زبان مقاله: انگلیسی
  • تعداد مشاهده: 264
دانلود فایل این مقاله

نویسندگان

S. Shourehdeli

Department of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran

K. Mobini

Department of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran

A. Asakereh

Department of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran

چکیده

A number of isentropic coefficients are used in the one-dimensional models which predict ejector performance at critical mode. Some of these coefficients have considerable effects on accuracy of the model. These coefficients depend on geometry, working fluid and operating conditions; but, they are usually taken constants or are presented as functions of geometry and working condition based on a specific experiment. In this work, the idea of using the flow parameters to determine these coefficients is introduced and has been analyzed. For this purpose, four models with different formulations are employed. The fluid has been considered as a real gas; hence, the models which are based on the ideal gas assumption are modified. The experimental data related to some ejectors with different geometries, working fluids and working conditions have been used. Using the empirical data, correlations between some of the isentropic coefficients and the flow parameters are developed for some models. Using these correlations, entrainment ratios are calculated with the maximum relative error of ۳۵%, while in most cases the maximum relative error is about ۱۰%. However, errors are acceptable since the empirical data are extracted from a vast range of different geometrical and operational conditions.

کلیدواژه ها

Ejector, Isentropic coefficients, performance analysis, Critical operational mode

اطلاعات بیشتر در مورد COI

COI مخفف عبارت CIVILICA Object Identifier به معنی شناسه سیویلیکا برای اسناد است. COI کدی است که مطابق محل انتشار، به مقالات کنفرانسها و ژورنالهای داخل کشور به هنگام نمایه سازی بر روی پایگاه استنادی سیویلیکا اختصاص می یابد.

کد COI به مفهوم کد ملی اسناد نمایه شده در سیویلیکا است و کدی یکتا و ثابت است و به همین دلیل همواره قابلیت استناد و پیگیری دارد.