طراحي پمپ حرارتي ترموآكوستيك در مقياس آزمايشگاه

DESIGN AND OPTIMIZATION OF A LAB SCALE THERMOACOUSTIC HEAT PUMP

كاربرد علم آكوستيك در ترموديناميك، دستاورد هاي جديدي در زمينه‌هاي مختلف علمي و صنعتي به همراه داشته است. وسايل ترموآكوستيكي به‌دليل داشتن مزايايي چون: نداشتن اجزا متحرك، كوچكي و سبكي، عدم ايجاد آلودگي‌هاي زيست‌محيطي و ... نسبت به وسايلي كه كاربرد مشابه دارند، توجه و علاقه بسياري را به خود جلب كرده است. در اين نوشتار با استفاده از نظريه‌ي خطي ترموآكوستيك، يك پمپ حرارتي ترموآكوستيك با رانش آكوستيكي در مقياس آزمايشگاه طراحي شده است. پارامترهاي طراحي به‌صورت كامل بررسي شده و نهايتاً الگوريتم كاملي براي طراحي بهينه پمپ حرارتي ترموآكوستيك ارايه شده است. معتبر‌سازي طراحي با به‌كارگيري نرم‌افزار E? انجام گرفت. سپس با بررسي تمامي پارامترهاي دخيل در طراحي و چگونگي رفتار پارامترهاي مختلف در عملكرد سيستم، از بهينه بودن نتايج اطمينان حاصل شد.

In recent years, due to international energy and environmental aspects, thermoacoustics have gained interest by being considered as an alternative technology for renewable energy utilization. Typical thermoacoustic systems deal with the conversion of heat energy to sound energy and vice versa. This phenomenon dates back more than a century. Recent advances in the field of thermoacoustics have altered the working mechanism of many conventional heating and cooling devices. Thermoacoustic systems have three distinctive advantages: first, they are simple in structure, have no moving parts, and have low manufacture costs with high reliability; second, by using inert gases as a working fluid, they are environmentally friendly, and; finally, heat driven thermoacoustic devices can be driven by low quality energy sources such as waste heat, solar energy, and etc. Although thermoacoustic refrigerators were developed in the early 1980s and despite recent remarkable achievements in thermoacoustic refrigerator systems, to the knowledge of the authors, less attention has been paid to the application of thermoacoustic prime movers and heat pumps. The main purpose of a thermoacoustic heat pump is to transfer heat from a cold reservoir to a hot reservoir via consuming acoustic power. The basic mechanism of a standing wave thermoacoustic heat pump is very simple and is based on the wave interaction processes of gas particles with their surrounding environment. The essential components of a stand-alone thermoacoustic heat pump include an acoustic driver (i.e., a loudspeaker), a resonance tube, a stack of plates, and heat exchangers. The present work deals with the design and optimization of a lab scale thermoacoustic heat pump using the linear theory. Different design parameters, as well as constraints, are investigated, and ultimately, an algorithm for optimization of thermoacoustic heat pumps and refrigerators is developed. The proposed algorithm is validated using DeltaE software. Further, a parametric study is carried out, where the effect of various design and operational parameters on the performance of the system is studied.