Research On Combined Cycle Of Armored Vehicle Turbocharged Diesel Engine And Air Refrigeration System

Armored vehicles are the main battle equipments of ground wars. With theadvancement of modern industrial and military technology, rapid developments in theperformances of firepower, protection and mobility of new armored vehicles have beengained. However, how to protect the crews’ comfortability and the working environment ofelectronic devices is lack of attention. Especially, there is no air conditioning system in thecrew cabin of the diesel-powered main battle tank.In this paper, the system energy loss, conversion and utilization of the diesel-poweredarmored vehicle were analyzed. A new combined cycle system was proposed, in which theair cycle refrigeration system was powered by the power turbine driven by the exhaustwaste heat energy of the bypass afterburning system and the diesel engine. The output shaftpower is the only coupling point of the air cycle refrigeration system and the compoundturbocharged diesel engine, which contains a bypass afterburning system and a powerturbine. Under decoupling and coupling conditions, the system parameters effect law andcontrol law, the designing and experiments of the refrigeration system key componentswere conducted. The main research contents are as follows:1. Based on the first law of thermodynamics, the energy transfer and conversionprocess of three air refrigeration system programs (the forward bootstrap program, thereverse bootstrap program1and the reverse bootstrap program2) were analyzed, and thecoefficient of performance (COP) and the function formulas of the main cycle parameterswere obtained. A preferred air cycle system program with the highest COP was chosen.Focusing on the ground battle conditions of tank and armored vehicle, an individualmicroenvironment air refrigeration mode was proposed, which could reduce therefrigeration system power consumption and improve the working environment of thecrews. The refrigeration capacity of the crew cabin microenvironment in an armoredvehicle was calculated, and the target output power of the power turbine was determined byconsidering the practical engineering applications.2. A preferred program was obtained based on the second law of thermodynamics by using the gray box exergy model to analyze the exergy flows of three programs: the parallelprogram, the serial program and the serial afterburning program.3. The power turbine was taken as the decoupling point of combined cycle system forstudying the effects of parameters of bypass afterburning compound turbocharged dieselengine and air cycle refrigeration system. Based on the effects of parameters of serialprogram and parallel program, the joint workspace of serial program in the whole engineoperation conditions was divided and the afterburning zone and the non-afterburning zoneof parallel program was also divided.4. The parameter control law of the purge valve opening in the joint workspace ofserial program was analyzed and the identified process of the parameter control in parallelprogram was obtained. Then the parameter control law ofm F,Bin the range of wholeengine speed at full load was obtained.5. The key components namely the power turbine in refrigeration system and thecompressor (C1) were designed and analyzed by CFD method and experiments, and theperformance test was taken on the gas performance test rig. A prototype of refrigerationsystem for diesel-powered armored vehicle was designed. Then the air cycle refrigerationsystem test platform was also established and the parameters effect law of refrigerationsystem was verified.6. The combined cycle system coupling simulation model was established and theinteraction effect of two subsystems from the system level was studied. Finally, the effectsof system parameters under the coupling condition were summarized and analyzed, whichprovides the reference for the environmental adaptability adjustment of system parametercontrol law in the practical engineering application.In this paper, the parameter effect law and control law of combined cycle system wereresearched by theoretical analysis, simulation and experiment. The results provide thesupport for the application of the air cycle refrigeration system on the armored vehicles,which fills the blank of air conditioning system of the diesel-powered armored vehicles.