Unilateral Refusal Of A Lease Agreement: Theoretical And Practical Aspects

The article deals with the unilateral refusal of a lease agreement as a way of self-defence of the tenant's and landlord's rights. The author expresses an opinion that unilateral refusal of a lease agreement by the tenant or landlord in cases provided by law or the agreement itself as a consequence of violation of the terms of a lease agreement should be considered is a sanction for illegal behavior of the parties of the agreement. The author notes that unilateral refusal of a lease agreement in case of breaching the agreement by the other party should not be equated to termination of a lease agreement at the request of one of the parties. They are independent grounds for termination of the agreement, which are characterized by a different mechanism of implementation, for example, the termination of a lease agreement at the request of one of the parties is always carried out in court. The analysis of case law shows that in order to be able unilaterally refuse from the lease agreement, when concluding an agreement it is necessary to state with a due precision the grounds for unilateral refusal for each party to the agreement. The author draws the conclusion that the simplified mechanism of unilateral refusal of a lease agreement should include two general stages: the emergence of grounds for unilateral refusal, and proper notification of the other party about the refusal of the agreement.

A Simplified and Optimized Chemical Mechanism for Combustion of n-Pentane at Atmospheric Pressure

In the present study, the detailed mechanism of n-pentane combustion, including 697 species and 3214 reactions, is first simplified to a mechanism with only 26 species and 134 reactions, which is suitable for the pressure of 1 atm, temperatures of 1000–1600 K, and equivalent ratios of 0.5–1.6. However, when the equivalence ratio is 1.0, in the temperature range of 1000–1100 K, compared with the detailed mechanism, the maximum error of the ignition delay time predicted by the simplified mechanism exceeds 20%. Therefore, based on the method of temperature sensitivity analysis, the simplified mechanism is further utilized through reducing the A-factor of 2HO2 = H2O2 + O2 (−1) and 2HO2 = H2O2 + O2 (−2) by 10 times. By comparing with the detailed mechanism and predicting the ignition delay time, laminar flame speed, species profile, and extinction residence time, it is found that the optimized mechanism has good accuracy in the applicable range, and is fully capable of simulating the combustion process of light hydrocarbon gas.

Chemical Kinetic Model of Multicomponent Gasoline Surrogate Fuel with Nitric Oxide in HCCI Combustion

This study presents a simplified mechanism of a five-component gasoline surrogate fuel (TDRF–NO) that includes n-heptane, isooctane, toluene, diisobutylene (DIB) and nitric oxide (NO). The mechanism consists of 119 species and 266 reactions and involves TDRF and NO submechanisms. Satisfactory results were obtained in simulating HCCI combustion in engines. The TDRF submechanism is based on the simplified mechanism of toluene reference fuel (TRF) and adds DIB to form quaternary surrogate fuel for gasoline. A simplified NO submechanism containing 33 reactions was added to the simplified mechanism of TDRF, considering the effect of active molecular NO on the combustion of gasoline fuel. The ignition delay data of the shock tube under different pressure and temperature conditions verified the validity of the model. Model verification results showed that the ignition delay time predicted by the simplified mechanism and its submechanics were consistent with the experimental data. The addition of NO caused the ignition delay time of the mechanism simulation to advance with increasing concentration of NO added. The established simplified mechanism effectively predicted the actual combustion and ignition of gasoline.

Direct numerical simulation of triple flames by using 2D reaction-diffusion manifold tabulation method

The characteristics of partially-premixed flames is investigated by simulating a series of triple flames with different variations of chemical equivalent ratio. A two-dimensional Reaction-Diffusion Manifold (REDIM) chemistry tabulation method is employed in the simulation and the results are compared with the methane-air 19-step chemical reaction mechanism. The performance of these two mechanisms is then assessed by using direct numerical simulations coupled with GRI3.0 detailed mechanism. It is shown that both 2D REDIM table and 19-step simplified mechanism can describe the temperature and main products accurately, however, for some minor intermediary products, predictions from 2D REDIM table is observed to be better than 19-step simplified mechanism. Compared with the 19-step mechanism, 2D REDIM table only needs to solve only the transport equations for CO2 and N2 species, which greatly simplifies the solution process of chemical reaction and provides a reliable solution for the numerical simulation of turbulence with higher accuracy. This work indicates that as a relatively advanced kinetic simplified method, the REDIM tabulation method can reduce the computational cost and at the same time retain the accuracy effectively.