An innovative Organic Rankine Cycle system for integrated cooling and heat recovery

Abstract

6Converting a portion of the waste heat into usable power by implementing Rankine and Organic Rankine Cycles 7 (ORC) on long-haul trucks is seen as a potential way to improve the overall system efficiency. To identify 8 techno-economical heat sources across the drive cycle of a Heavy Duty Diesel Engine (HDDE), an energy and exergy 9 analysis was performed on all the available heat streams. As a result, to recover the combined exhaust gases and 10 coolant heat, a reference cascade system was analysed. Owing to the nature of this application, a size vs. 11performance optimisation was performed for the cascade system utilising water and R245fa fluid combination. Despite 12 a 1.8% Brake Thermal Efficiency (BTE) improvement, the key consideration in the research and development efforts 19HYSYS V8 showed that, compared to the reference cascade system, the proposed dual-pressure system has the 20 potential to deliver an average of 20% improvement in the system power, a 50% reduction in the total heat exchanger 21 footprint, and a reduced system complexity. These advantages bode well for an integrated and relatively compact

Fluid Selection of Transcritical Rankine Cycle for Engine Waste Heat Recovery Based on Temperature Match Method

“…The concrete working process of SR-TRC is: the working fluid transferring heat from jacket water in the preheater (2-3) is split into two parts, namely, high-temperature branch (H-branch) and low-temperature branch (L-branch). The working fluid in H-branch completely absorbs waste heat from exhaust gas in the gas heater (3)(4)(5) and then generates power in the expander-generator (5)(6), whereas the working fluid in L-branch streams through H-regenerator (3)(4) to absorb heat after expansion and then generates power (4)(5)(6)(7)(8)(9)(10)(11). After the working fluid of H-branch streams through the H-regenerator (6-7), there still exists recoverable heat to be utilized.…”

Two-Phase Expander Approach for Next Generation of Heat Recovery Systems

“…An integrated engine cooling and exhaust heat recovery system (Fig. 3), which was first proposed by the authors (Panesar, 2017), is considered using two-phase and superheated expansion approach. This integrated system uses a single working fluid to recover heat directly from the engine block and the exhaust heat exchanger by utilising a dual pressure architecture.…”

“…Due to the available extensive fluid database and property packages, the earlier identified preferred working fluid for the combined engine cooling and exhaust heat recovery, i.e. water-propanol mixture, was utilised (Panesar, 2017). The present expander model requires limited input data, which includes:…”

How to select regenerative configurations of CO 2 transcritical Rankine cycle based on the temperature matching analysis

“…Organic Rankine cycle system is presented for its advantages such as small size, lightweight equipment, economic investment, wide applicable ranges in heat source temperature, energy efficiency improvement, environmental protection and stability performance. [1][2][3][4][5][6] In Ref., using ORC to recover waste heat can achieve up to 30% improvement of output electrical power for diesel engine, 7 1.2%-3.7% increment of thermal efficiency 8 and dramatical reduction of CO 2 emission. 9 CO 2 transcritical cycle was proposed as a suitable form for waste heat recovery.…”